178 comments

First Understand, then Destroy, your Home Heating Bill

A $40 insulation job on the garage door of my previous house saved hundreds of dollars of fuel. And made the garage a much more pleasant place to work.

We’ve all read the tips in the newspapers about how to reduce our heating bill. Turn down your thermostat and get a programmable one. Seal your air leaks. Add insulation to your attic. Blah blah blah.

It’s boring, but it’s powerful advice, because US households spend an average of about $960 each per year keeping themselves warm. That’s three months of grocery money for a family, pumping heat into a leaky sieve that could actually have been built to require much less, or even no added heat, depending on the location and climate.

So while the USA Today-style heating articles are good enough for those readers, they’re not good enough for us. I don’t just want to lower my heating bill, I want to Destroy it. My eventual goal for any house I settle down in for the long run is to make it require no fossil fuel energy to keep it warm all winter.

To understand heating, you must first know what you’re paying for. Heat is often measured in BTUs, British Thermal Units. 100,000 BTUs is referred to as a “therm” on my Natural Gas bill, and a therm currently costs about $1.00.

Then you must understand how you are losing your heat. The most important form of heat loss from your house is something called thermal transmittance, also known as U-factor. This is really just a number that means “how leaky is this material”, and it is based on the leakiness of a single pane of glass.

A single-pane glass window has a U-factor of 1. In English units, this means that each square foot of glass leaks out one BTU of heat per hour, for each degree Fahrenheit your house is warmer than the outside air.

So when you’re looking through a giant 10×10 foot window (100sqft), from a 70F room out into a 0F deadly-cold wintry blizzard, your window is leaking out 100 x 70 = 7,000 BTU per hour of heat into the night. That’s  7 cents per hour or  $50.40 per month of heat from that single window.

The “R-value” you have probably heard about is simply the inverse of the U factor. That means 1 divided by U equals R, and 1 divided by R equals U. You’ve heard of R-13 wall insulation, right? The U-factor of that is 1/13, or 0.08.

With that knowledge, we can move up to understand the heat loss of an entire house. A 1000 square foot house probably has an outside surface area of about 2000 square feet including the roof. If it has standard R-13 wall insulation (and no windows for this example), and the temperature inside is 68F,  it loses how much heat on a 32 degree day?

2000 square feet x 0.08 U-factor x 36 degree temperature difference = 5760 BTU per hour = $1.38 per day.

“Hey, that’s a pretty cheap gas bill for a whole house in what sounds like a pretty cold climate”, you say. But wait, it gets even better.

Imagine this household uses the same amount of electricity as me, about 299 kilowatt-hours per month, equivalent to 415 watts of average continuous use. How much heat does this electricity use add to the house? The answer is 1416 BTU per hour.

“What? You were just talking about home heating, and now you are talking about electricity.. aren’t they two different things?”.

No, it turns out they are actually directly related. Almost all of the electricity you use in your house ends up being converted to heat, with 100% efficiency. Your light bulbs give off heat and light, and the light bounces around the room and eventually gets absorbed by the walls and turns into a tiny amount of heat as well. Likewise for your appliances, your computer, etc.

What this means is that any electricity you use in the heating season provides some of your heat, and reduces the amount your furnace needs to provide. The only exception to this rule is electric appliances that vent their waste heat outside, such as a clothes dryer or exterior lights. But we don’t use clothes dryers, right?

So let’s go back to the 1000 square foot house. It needs 5760 BTU per hour to stay warm, and it gets 1416 of those BTUs just from the electricity you use while living there. So you’d still need the furnace to stay warm.

But what if we increased the wall and roof insulation to R-53? That quadruples the insulation, which cuts the heat loss in four. And guess what – you have a self-heating house!

Practical Example: the attic of this house is 1000 square feet. We want to quadruple the insulation from R-13 to R-53. To add the extra R-40, you’d simply have to blow in about 12 inches of cellulose insulation. This would take 61 bags of the stuff, which costs $610 before tax credits.

Adding $610 of insulation to your attic is saving you about $15 per month of heat in this situation – $60 per year over a four-month heating season. It will also cut your air conditioner use. So it’s at least a 12% annual return on investment, forever.

The self-heating house is the holy grail of home heating, and this is the way houses in many parts of the US could be built to destroy their winter heating bill. With proper design, the cost of the extra insulation would be small compared to the energy savings. Changes like this are really coming – the 2003 and 2007 international building codes, which most cities and towns adopted for all new construction, have much higher insulation standards, meaning lucky homebuyers in the future will have much lower costs.

Now, my example was kind of silly, because the house was just a simple 25×40 rectangular box with no windows. What if we add windows?

Good double-pane windows have a U-factor of about 0.3. If the sample house has eight 3×5 windows (a total of 120 square feet of glass), this adds a heat loss of about 1296 BTU per hour. D’oh! There goes almost all of the free heat we get from our electricity! How can we recover? Luckily the windows come with some good news too.

Solar gain at work in MMM’s room. Shutters open in day, closed at night.

Let’s say the smart designers of this house put two thirds of the windows on the South side of the house. The sun shines an average of five hours per day in this region, delivering 1000 watts per square meter (90 watts per square foot) mostly onto the side of the house. The windows let a certain amount of this heat into the house, based on their solar heat gain coefficient, which is usually around 0.3, or 30%.

There are 80 square feet of glass on the South side, getting hit with 90 watts per square foot of light, and 30% of the heat makes it into the house. This is 2160 watts of heat for five hours, or 36,850 BTU of heat per day shining in. Averaging this over the 24 hours of a day, your house now has an extra 1535 BTU per hour of heat coming in, just from the South-facing windows.

The lesson is: having 2/3 of the windows facing the Sun more than made up for all of the house’s total heat loss through all of its windows!

Rule of Thumb: Each 3×5 window facing South gives you about $2 per month of free heat (in a moderately sunny climate).

You can drastically improve the performance of your windows by using shutters or curtains on them. Open them when it is sunny, and close them at night and even on cloudy days if you wish. A tight-fitting curtain or honeycomb blind, or better yet a set of interior shutters, can cut heat loss through the windows in half again. Just remember to open them back up when the sun is shining in the window.

The final easy thing under your control is the interior temperature. As we’ve seen above, the heat loss from your house depends entirely on the difference between the interior and exterior temperature.

Supposed that I lived in San Francisco, where the average winter temperature (day averaged with night) is a moderate 50 degrees Fahrenheit. If I keep my house at 50, I will need to add absolutely no heat to it to keep warm. If you keep your house at 70, you will need some heat, and if someone between us likes 60 degrees, she will use exactly half of the amount of heat you use.

So when you drop your interior temperature, it saves you some cash. Even if you just let it fall for a few hours while you go out for a walk or while you’re at work, it still saves heat because you are lowering the average difference between interior and exterior temperature.

In my climate in January, the day/night temperature averages to 30 degrees. If an average person keeps his house at 72F (a 42 degree difference), and I keep mine at 67F (a 37 degree difference), my gas bill will be about 12 percent lower than his. If I further lower my average by dropping the temperature at night to 60F, I can save an additional 8%.

Lesson: Running your house at 67F during the day and 60F at night will save you about 20% on your gas bill compared to a house that runs at 72F around the clock.

So we have covered the big three: insulation, solar gain and window loss, and interior temperature. With the right combination of these three things, and enough thermal mass to keep your temperature nice and constant, you can have a self-heating house.

The MMM family house is not a trivial one to heat, so it has no yet attained this status, but I am getting there. It’s about 2600 square feet in size, with 1800 of that above the ground. There are about 30 exterior windows and doors, some of them pretty big, and they are not (yet) all that well optimized for capturing solar heat. And most significantly, it houses a lady of Indian descent and a young boy, who both become quite unhappy if the interior temperature drops below 67 degrees Fahrenheit (19.5 Celsius) during the day.

I have made these changes so far, with the approximate annual dollar savings listed alongside them:

Added 20 bags of blown-in insulation to the attic: $25
Insulated the steel double garage door: $25
Using 10 insulated shutters to close second floor windows each night: $50
Opening shutters on 6 large south-facing windows to capture solar gain: $50
Covering large rarely-used basement windows with removable insulated plugs during winter: $20
Running lower interior temperatures, especially at night: $80

The total savings so far are about $250 per year, meaning the heat bill was $650 per year when we moved in here, and now it is $400. That’s a 40% drop. Some of the remaining 60% can be wiped out like this:

150 square feet of solar gain glass on South side (nearly free from recycled building materials store): $80
Much more insulation in the part of the attic I didn’t get to yet: $50
Insulated shutters for the large remaining windows: $50
Solar collector on the roof for domestic hot water and  radiant solar heat: $50.

That cuts the bill down in half again to $200 per year. But after that, I’m out of ideas. Our current house is not an energy-efficient design to begin with, so it is difficult to get it fully self-heating. More changes could be made, but they would become more exotic and thus cost more than they delivered in savings.  A future home of ours someday, however, will learn from the limitations of this one and have natural heat built in right from the drawing board. Perhaps yours will too!

Update: This article was written way back in 2011. A couple years later, we moved to a “new” house (actually a 1959 house which I bought then rebuilt nearly from scratch). It is a smaller place with a much better orientation to the sun, and I used all of the principles in this article. As a result, it is much closer to optimal, getting nearly all of its heat for free and requiring no cooling in summer. An dream come true for both engineers and nature lovers, since the view is all sunshine and trees from most rooms.

 

 

Bonus Points: After I skimmed the surface with this article, the readers posted a bunch more useful energy-saving techniques in the comments below. Check them out for more learning, especially Brian M’s comment about sealing leaks in an older house. Air leaks are even more important (and cheaper to fix) than insulation, so if you still have any of these around, fix ’em.

 

  • Chris November 18, 2011, 6:27 am

    What about the heat generated by the people inside the house?

    Reply
    • MMM November 18, 2011, 7:01 am

      Oh yeah, I should add that when I get a chance. One nutritional calorie (kcal) is about 4 BTU. So if you are home all day and burn 2000 calories a day, that is 8000 BTU. That’s only 8 cents of heat per day, but with four people, home half of the time, you get $5 per month of heat.More if you have a big party :-)

      Reply
      • Chris November 18, 2011, 7:26 am

        Cool, it seems like it is quite significant in my smaller apartment. :)

        Reply
        • Bakari November 21, 2011, 8:17 pm

          Yep, in the closed bedroom of my little 250sq ft RV, in is much warmer in the early morning after two people have been sleeping in it all night than when we went to sleep, even though the early morning is the coldest part of the day

          Reply
    • Belcat January 31, 2012, 1:40 pm

      From the Passivhaus initiatives I’ve seen, they usually consider a person to be about 200 Watt-hours on average.

      Reply
  • Cass November 18, 2011, 6:29 am

    This is all great – if you own a house. But I’m a student, and I rent. And while I’ve worked hard to get my electric bill down (by about 1/3) I’m finding it hard to get much below that. (I get none of my energy from gas – all electric).
    We are lucky to have south-east facing windows, giving us a lot of heat during the day. Unfortunately, the building was built in the 70’s, and has not been updated any more than the minimum, with no control over the water heater. But other than insulating curtains and sealing the windows with plastic, I’m not sure how else to insulate?
    How can apartment dwellers reduce their electric bill effectively?

    Reply
    • Kevin Schwartzenberg November 18, 2011, 8:30 am

      There are several other things you can do in an apartment. I live in a rental in Chicago that was built around 1900 and it leaks like a sieve. The first winter our gas heating bills were over $300 for a couple of months, even at reasonably cool interior temperature. Since then we’ve done several things to improve our heating bill and now it peaks just over $130 in the coldest months.

      – Open the blinds/curtains on windows that get a lot of exposure during the day
      -In addition to sealing the windows, check out your doors. Often times there are gaps between the door and the frame that can be sealed with foam tape.
      -Install door sweeps on exterior doors to further seal them
      – If you have windows or doors that rarely get used and don’t provide useful light or nice views, consider sealing them in the winter. At our old college place we had a secondary exterior door that had single pane glass. During the winter we built a plug out of 1″ thick extruded polystyrene board and covered it up.
      -Lower the temperature further. A pair of slippers, some sweatshirts, and a good down comforter go a long way.
      -If you do not have a programmable thermostat already, talk to your landlord about installing one. They are cheap (like $30), they make ones that will fit the same area as the old school round metal ones that might be installed in your ’70s apartment, and they are super easy to install. Worst case scenario, see if your landlord will let you do it if you pay for the upgrade. They have the potential to pay for themselves in one winter.
      -MMM talked about keeping the house a bit warmer in the day time and colder at night, but if you have not yet reached financial independence and your apartment is empty during the day, it may make more sense to reverse that. This is where the programmable thermostat is great. My room mate and I both work during the day, so we would program the temperature to drop to 58F beginning at around 9 AM when we were either gone or on our way out the door, then turn back up to 64F an hour or so before we got home. Since your heat is electric, you may reap even more benefit from this strategy since you will be avoiding those peak usage hour rates. If you go all out and get a 5 point programmable thermostat you can further optimize your heating schedule by dropping the temperature back down while you are asleep, say from 11PM to 6 AM.

      Reply
      • Steve November 18, 2011, 9:34 am

        One warning about dropping heat during the day. If you are using a 1-1 heat like electric, then you should be doing as you suggest.

        However, if you run a heat pump, and day time temperatures are warmer than nighttime temps, it could be in your favor to transfer this heat into your house using the heatpump than to wait until those temps fall along with the efficiency of your heat pump.

        Reply
      • MMM November 18, 2011, 9:41 am

        Thanks for sharing that, Kevin!

        Another slightly funky tip – if you have a large exterior wall in an apartment with no windows on that wall, you can hang a big decorative blanket or rug over the whole wall, and make sure it is fitted tightly to the wall. You can even hide additional insulating materials behind the rug. This could double a wall’s R-value in the case of an uninsulated 1900s building. Overall though, addressing the windows is the biggest bang for the time invested. As you said, a fitted window plug with styrofoam or reflective polyiso board can increase a window’s insulation from R-1 all the way to R-10 or beyond. Throw them in at night and when you are away, and cut the heat loss significantly.

        Reply
        • Belcat January 31, 2012, 1:44 pm

          Careful about rugs – if they are actually good enough to insulate enough, they may cause the temperature on the side of the rug on the wall to drop. If the temperature drop is enough and the humidity is high enough, condensation will occur and the rug will get wet, and mold will start to grow.
          Though, typically apartments are very dry unless you run a humidifier..

          Reply
        • SAra May 5, 2016, 9:29 pm

          When my husband and I were living in a 100-year-old barn’s loft that had been converted into an apartment, this is exactly what we did. We hung a big wool blanket with a pretty wolf print over the entire west-facing wall (which had NO insulation and always had the wind against it – the building was slanted eastward from the constant blowing). Our apartment was absolutely tiny, with more square feet of poorly-insulated slanting roof than floor space. But that one blanket made a big difference – especially when the furnace died! Our utilities bill there was always horrible, but at least we stopped the ice from forming on the inside of our wall.

          Reply
    • Ivan November 18, 2011, 10:29 am

      Use bubble wrap to insolate your windows. Seriously. It will help reduce the heat lost about 20-30%

      Reply
    • Bakari November 21, 2011, 8:22 pm

      the biggest – and easiest – way is to just insulate the thing you really need kept warm: your body.

      If you notice, in the list of cost savings at the end of the article, the thing that made the biggest difference in cost was just turning the heat down.

      I started wearing a hat and jacket indoors, and cut my heat bill down to zero!

      Reply
      • MMM November 21, 2011, 9:57 pm

        Yeah, and on a similar note, one of the refrains we have around my house if someone complains about being cold is “TWENTY PUSHUPS!!”.

        Because as it turns up, 20 pushups always warms you up much faster than your furnace can do it. For longer-lasting heat, make it 50 pushups and add 25 deep knee bending jumps as high as you can.

        And, admit it, we are all a bit flabby and would be a bit less so after fifty pushups and 25 jumps.

        Reply
        • EarningAndLearning April 26, 2017, 3:51 pm

          Ha ha my Dad used to make us do push-ups when we’d complain about our chilly Calgary home, which my Mom kept cold during the day and freezing (heat off entirely) at night. She was so frugal she refused to program the thermostat to turn on at 6 am so it would be warm by the time we basement-dwelling teens had to get up, she only turned it on manually when she woke up around 7. Ugh it was torture.

          But now that I’m adult with electric baseboard heaters (pricey!) I keep the apt quite chilly myself all winter :)

          I find that a nice mug or two of piping hot herbal tea warms the body right up! I drink a lot of tea in winter. That and a nice flannel scarf (sometimes even a toque – yes, I’m Canadian & we really do call them toques) also does the trick! Old school, but it works!

          Reply
    • Amanda November 26, 2011, 9:13 am

      Totally there with you. I’ve been renting for 4 years. Some things you can do:

      Stick with a small apartment. My 350 sq. ft. place costs about $500 to heat year-round, vs. the $800 my friend pays for a bigger place. And that’s before I winterized it.

      Rope caulk is your friend. Around November, walk around with a roll and caulk the crap out of any tiny little gaps you see near windows and doors. I lined my leaky wood windows with rope caulk and it make a drastic difference.

      Get some of those thermal curtains. They’re awesome for blocking out light and noise at night, and they keep heat in. Just open them when it’s sunny.

      You can still insulate ceilings if you have those crappy removable ceiling panels that most apartments have. Just roll out some insulation on top of the panels. I did that in my place and even with the cost of insulation, I’ll save money in a year. When I move, I’ll just take my insulation with me for the next place (yup, I’m cheap like that). Or I’ll sell it for a few bucks on craigslist. It helps to get the plastic-wrapped insulation for this, btw.

      Wear a sweater and turn the heat down. My heat is kept at 64F max when I’m home, and 58F when I’m not. It sucks at first but then you adjust.

      Reply
    • Belcat January 31, 2012, 1:45 pm

      Make sure the window plastic is over the frame of the window – the frame often leaks as much as the window!

      Reply
  • Jeh November 18, 2011, 6:44 am

    Tons of great info, thanks MMM!

    My dream home, which happens to be self-heating (and self-watering, and self-electrifying…it has it all): http://www.earthship.org

    Reply
  • TOM November 18, 2011, 6:50 am

    So do you have any value for keeping the curtains open on North/East/West-facing windows during the day in the winter? I would imagine there’s pretty minimal solar gain.

    Reply
    • qhartman November 18, 2011, 9:01 am

      You might get some from the West windows in the afternoon, but it’s probably not worth worrying about, especially if you live north of 40 degrees latitude or so. The East is less useful than the West (at least where I am) since there’s usually fog or cloud cover to burn off in the morning. North is essentially zero gain (likely even some loss) anywhere in the Northern hemisphere.

      Reply
      • Mackenzie April 23, 2015, 11:41 am

        For me, we found that in the summer putting a blanket over our west-facing window made a HUGE difference in solar gain. That’s the one we make darn sure we keep the curtains open on during the day in the winter.

        Reply
  • ermine November 18, 2011, 7:24 am

    > equivalent to 415 watts of average continuous use

    You need to get that down to be truly Mustachian in this respect :) This figure is 160 for me. OK so there are only two people in my household, but there’s scope for improvement.

    Electricity is an expensive way to heat a home compared to natural gas, and it also adds to your heat load in summer. I agree with the principle if you’re going to use that amount of power you may as well use the byproduct, it would still be cheaper to draw less electrical power even if you had to use natural gas to make up the loss.

    I’ve never run the heating at night, just let the temperature drop slowly till about an hour before getting up for work. That’s why you have a duvet, and a significant other :)

    Reply
    • MMM November 18, 2011, 9:05 am

      Mr. Simple Living in Suffolk, this is the THIRD time you have challenged me in the comments about my electricity use! I already know my 66% reduction over the US average electricity use is still wasteful.. but you may have to talk to my wife and son if you really want this number to drop – they are the ones living the cushy life.. I just play the role of engineer to make it all happen with minimal waste given the circumstances :-)

      I’ve had the power meter measuring all of the use in my wife’s office over the past month. It’s almost 30 kWh, or 10% of our home’s energy use! There’s a brand-new computer, on most of the day, using 30W active, 1W standby.. a new LED monitor using a similar amount, a CFL desk lamp for when the sun is down, a laser printer (on only when printing), a cable modem, and a wi-fi router (both always on).

      On the positive side, this home office brings in a lot more cash than it burns off, and as I said earlier we are using wind power and our cost per kWh is only 9.5 cents for pure wind – some of the cheapest green power in the world as my city owns its own utility company.

      Reply
      • ermine November 19, 2011, 2:02 am

        Well, it kinda sticks out as non-Mustachian :) The office drain isn’t so bad, it’s a little less than my fridge. However, chasing down all the little drains on power is hard, but you have to get them all – the transformer that samed me having to change batteries on my doorbell was drawing a steady 25W f’rinstance, and tracking these down is hard. I KO’d about 100W of parasitic drain by nailing these ghost loads. I reduced my power draw by 75% by tracking down each and every one of these things, but the last 50% was hard work to identify.

        I do think the argument that your electricity usage defrays heating costs is specious. For a start. good energy design targets the heat to where it’s needed when it’s needed, and also this parasitic heat doesn’t go away in summer, where it is hot in CO I believe ;) So you get to be more comfortable in winter and less comfortable in summer.

        On the same logic of using the waste heat, maybe a case to reinstall your incandescent light bulbs then, on the grounds they wil give you heat in the winter when needed. I’ve read people making that argument, even in the IET elecrical engineers’ journal letter pages, though they usually get pulled up in the next issue.

        So having established your wife’s office isn’t that bad a load, maybe you have a hot-tub out in the backyard…

        Reply
        • MMM November 19, 2011, 9:17 am

          Wow, that’s a big doorbell transformer – perhaps your house has a bell tower.

          Still, inspired by your comment just now, I went down to my furnace room with the multimeter and unwired my own doorbell transformer: 52.3 milliamps = 6.3 watts. That is about 55 kilowatt-hours per year, or $5.50 in electricity my doorbell was using for no reason!

          That works out to costing me about one beer for each time someone I actually want to talk to, rings the doorbell (since friends usually just walk right in, while the solicitors are the doorbell-ringers).

          Better yet, I can replace the transformer with a single little 12-volt battery or possibly even a 9V, and still retain doorbell functionality without the annual cost.

          Thanks Ermine, any more parasitic load tips? (I’ve already measured everything plugged into the wall outlets and eliminated unnecessary things. My video projector was using 15W on standby, for example.

          Reply
          • AdventurousZ June 26, 2014, 9:57 am

            I unplug my wifi router/modem at night. For electricity and health reasons.

            Reply
          • Machteld January 30, 2016, 1:00 pm

            How about just a simple doorknocker? No electricity costs and some good old-fashioned muscle over motor activity. Plus doorknockers look cool on a door. I’m quite happy with mine :)

            Reply
  • Mark November 18, 2011, 7:25 am

    Could you post some details on the $50 solar collector for domestic hot water? Is that the same as a “solar water heater”? I had ruled out getting one of those systems because it looked like most of them were over a thousand dollars.

    Reply
    • MMM November 18, 2011, 9:07 am

      Unfortunately, the $50 number is my estimated annual heat savings, rather than the cost of the heater itself. To profitably add the hot water collection system, I have to find a way to build it for less than $500 of cash so I can get a 10% annual return on my investment.

      That is why I have decided to wait until I have time to build my own using recycled building materials, rather than buying a commercial system for $2000. At 2k, I’d want it to provide at least $200 per year of free heat, which is possible but I haven’t found a system that meets this need yet. Maybe other readers can provide some links if they find a system.

      Of course, it can do double duty as a hot water heater year-round AND a home heater for winter, and there is more heat available in the summer. My annual water heating cost is about $120-$150. If I could eliminate this, this would justify a much fancier system, perhaps even up to $2000!

      There are also federal tax credits in the US that cut the cost by about 30%. But I haven’t looked into the details yet. Once the foreclosure project is complete, the Energy Independent MMM Household Project will get underway.

      Reply
      • MikeK November 18, 2011, 11:55 am

        You should check out this website for a ton of ideas to build your own solar stuff. They are working on perfecting a $1K solar water heating system (solar collectors and storage tank). I believe it’s been adapted to do radiant floor heating as well. With your mad Mustachian skills, I’m sure you could build one for less!

        http://www.builditsolar.com/Projects/WaterHeating/water_heating.htm#1KSolarWater

        I really want to build this system (got 3 kids coming of shower age, not looking forward to the hot water bills!) but I’ve got lots of large trees to my south that block much of the sun.

        Reply
      • Jamie Forrester November 18, 2011, 8:33 pm

        The site for build it yourself Solar water/space heating

        http://builditsolar.com/Projects/SpaceHeating/DHWplusSpace/Main.htm

        He gives full performance and payback numbers for his system. The water heating payback is here

        http://builditsolar.com/Experimental/PEXColDHW/Cost.htm

        It suggests savings of $250 to $300 per year in his area depending on our current fuel source and it’s costs.

        Reply
        • MMM November 18, 2011, 11:11 pm

          Wow!! That is an amazing description that guy has put together on building the solar heat collecting system. I think I’ll just follow his instructions exactly, and send him a big thank-you letter as well. It looks like it would be quite fun to build. Thanks Jamie for posting that link.

          Just a note that he is using $2-per-therm as his price for natural gas, while the actual price is less than $1 these days, and it has been for a while. So while the potential savings are cut in half, I think the system would deliver more winter energy in my area, since I am two states closer to the Equator than he is in Montana :-)

          Reply
          • brenda from ar October 28, 2012, 6:49 pm

            He has written for Mother Earth News. I read about his contraption for day-heating for his workshop – a south facing collector box with a couple of layers of black screen wire. From that I put a layer of black woven fabric behind my curtains in the sun-facing windows. Allow air to enter at the bottom and exit at the top. In full sun, I got a 17 degree rise from bottom to top and the flow would nearly float a feather. Even with bubble wrap on the glass, I got a 13 degree rise. Cut bubblewrap to fit, mist glass w/water, stick bubblewrap to glass. The advantage of having the bubblewrap on during non-sun seemed to outweigh the 4 degree difference. So, this isn’t intended for your gorgeous view windows. Very fun experiment.

            Reply
            • Chad July 22, 2015, 1:26 am

              I doubt the effectiveness of your solution. For a solar heat solution to be effective, it has to capture heat that would otherwise be lost. In this case, it has to absorb light that would have been lost. Tell me, how much of the light that enters your home also happens to find it’s way back to another window to exit your home? If so, the rest of that light has to be being absorbed by other materials in the home, so you may be generating more heat at the window, but I question how much heat overall is being captured by this process above what would have been captured throughout the home as a whole otherwise.

          • Justin Manges August 24, 2013, 6:12 am

            I can’t believe no one has mentioned wood burners on here…. My cousin has a huge one out side his 2800 sq ft home. It heats up water which is pumped in to heat up his house. He gets free fire wood all year so his heat is virtually free in the winter (besides the cost of running the fan and pump) And the best thing is its off in the back of his yard.

            Reply
      • Joe Average July 28, 2015, 8:41 am

        Look up evacuated tube solar collectors. I’ve worked with a system like that as part of an engineering project and the thing was capable of making small quantities of steam on a mild day.

        I imagined a system like that feeding hot water radiators or under floor heating for winter heat with a solar powered pump.

        Reply
  • Gypsy Geek November 18, 2011, 7:38 am

    So I can reverse your entire analysis if I live in hot climate, right? :).

    I have an attic, with no insulation, and it’s always really hot up there. Do I use the same insulation as you would use up north, and save the comparable amount in cooling costs? Or is there a different type of insulation for hot weather?

    Reply
    • qhartman November 18, 2011, 9:02 am

      Same stuff works.

      Reply
    • Steve November 18, 2011, 9:38 am

      You could also try radiant barrier. I put some in my attic and it was amazing how much radiant heat it kept from entering the attic. I hope it’s still frugal this winter.

      Reply
    • AGil November 18, 2011, 10:29 am

      Also install a thermostat controlled attic fan, that will help dramatically by removing the hot air before it has time to soak through the ceiling. Note that there will be electric consumption, but this should greatly offset your AC bill. If it does not it will “waste” energy, albeit make you much more comfortable.

      If you live in a windy place this is not necessary, just vent the attic well, and nature will remove the hot air for you.

      I have installed a powered attic fan and swear by it. My AC runs much less now. Running a 100 watt fan vs a 20000 watt central air conditioner translates into huge savings.

      Reply
      • ted December 22, 2011, 10:49 am

        Seal attic from living space first. Powered attic fan will draw air conditioned air from living space if attic is not well sealed

        Reply
    • Belcat January 31, 2012, 1:56 pm

      Also make sure your soffits are OPEN (often idiots stuff insulation in them, or they just are too lazy to leave them open). Soffits matter way more than the rooftop (gable) vents, but adding another gable one may improve things a bit, and they don’t move, so they aren’t going to break down and need fixing for a long time.
      You can also get solar attic vents which may not payoff as fast, but you’re done with the hydro cost period.

      Reply
    • Erica W January 12, 2013, 12:35 am

      Excellent post.
      There’s also some good passive-solar techniques for hot climates.
      Hard to find on the Web, but look into Arabic, Moorish, Persian, Pueblo, and Mission style architectures for good examples.
      Shade and cross-ventilation are huge in all warm climates. ‘Solar chimneys’ use hot air’s rising draft to pull warm air out of the building and replace it with cool air drawn through a shady courtyard, collonade, or basement – an ordinary house with a central staircase and good attic vents can use its hot attic and cool cellar to perform this trick all summer.
      Pools and fountains can further cool the air, and you can also use a pond to reflect more light in during winter. (Great examples from Persia, India, Mediterranean and nearby regions.) Arrange for summer shade but winter sun (deciduous plants around pond, for example, if sun angles don’t quite work out).

      Different techniques are appropriate in humid vs. dry climates – in deserts, thermal mass is one of the best techniques because it allows the night-time cold to soak away some of the daytime heat.

      There are a lot of ‘solar angle calculators’ online – very useful in temperate zones. Because summer sun is higher, you can set up eaves or awnings that will shade the windows in summer but allow full solar gain in winter (or even fall through spring). You can also use compass orientation of windows to choose which months and which hours you collect more sun.

      Most ‘classic’ house designs have these features built in. It’s just learning how to use them (like the drapes), and ideally choosing a house style that was designed for a reasonably similar climate.
      Apartment dwellers may not have the control, but have the advantage that heating and cooling loads are WAY lower with shared interior walls. Denser-dwelling folks may be doing more for the planet than frugal isolationists; New York City has one of the smallest energy footprints per capita.

      Reply
  • JJ November 18, 2011, 7:45 am

    Question for you. I have older windows on the South side of the house that capture a lot of sun in the winter. The beauty is, these same windows are shaded in the summer thanks to trees. My question is…

    Should I be careful about replacing these with newer windows since the new ones have a special gas in them that can prevent the heat from the sun from getting through. My understanding is that newer windows don’t allow as much solar heat through and I’m wondering if the older windows would actually be better.

    Reply
    • qhartman November 18, 2011, 9:08 am

      I recently replaced all the windows in my house with scary triple-pane super insulated things, and that was something we discussed as well. We had an option to get windows that had higher heat transmittance from the sun, but that also meant a lower R-value. Given the orientation of our house and the terrain around it, etc, etc, we ended up decided that the gain from the higher R-value was more than we were losing with the lower transmittance on the South side of the house.

      It sounds like if you’ve got a good thermal mass inside those windows to actually capture the heat that’s coming in, there’s a chance the old single panes might be a net win, but it’s hard to say without more information. My gut tells me you’d still be better off with some double pane windows.

      Reply
      • MMM November 18, 2011, 9:45 am

        Good point – in a sunny area, you could theoretically get the best result by using single-pane windows that are exposed when the sun is shining, then cover them up at night or on really cool cloudy days. For lazier and more automatic living, just get standard double-pane low-E glass.

        It also depends on your location. Where I live right now, there is over twice the annual number of hours of winter sunshine compared to the cloudy great lakes region where I grew up. So South-facing windows are a bigger payoff here, while people back home get more benefit from highly insulated double or triple-plane windows.

        Reply
    • mugwump November 18, 2011, 9:36 am

      That is true. We had some older windows that we replaced, and we get significantly less heat in the winter through the new ones. Also, we gain less heat in the summer, though. The new windows are low E. I have heard that there is a high solar low E filter that doesn’t reduce the winter solar gain so much, but I don’t know if it is available on commercial windows.

      Reply
  • KevinW November 18, 2011, 8:16 am

    Are you familiar with passive solar design?

    http://en.wikipedia.org/wiki/Passive_solar

    Houses that are explicitly built and designed using the principles your talking about work great without any heating machinery whatsoever.

    Reply
  • Kevin M November 18, 2011, 8:50 am

    I freakin’ love this post. I love the number crunching and analysis – probably the CPA in me. I can’t wait to do something like this for my house. Our heating bills top out at about $100 per month in the dead of winter, but one time costs like more insulation are probably still worth it in the long run. One question – is it really necessary to insulate your garage door? I only have one interior wall that borders the garage and it shouldn’t lose much heat since there is a laundry room and staircase buffering the “living space”.

    Reply
    • qhartman November 18, 2011, 9:12 am

      When I was growing up in Denver, my dad insulated the garage door on our house. I don’t know what effect it had on our heating bills, but garage became usable as workspace in the winter without heating it directly. Extrapolating from that, it stands to reason that it must have saved on our heating at least a little, and it also meant that we didn’t turn on the space heater when we went to work out there, which represented another savings. I’m guessing over the 20+ years that insulation has been up, it’s worked out to be a net positive investment.

      Reply
      • MMM November 18, 2011, 9:50 am

        Yeah, the garage door is worthwhile in my situation because I just did it myself using cheap R-13 batts (total cost about $30), and this attached garage is bordering the kitchen on one side and the master bedroom above – about 600 square feet of exposure overall. The other two walls of the garage were already insulated and drywalled, so most of the heat loss was through the metal door.

        Before insulation, the temp would drop to 30 degrees or lower at night. After insulation, it is 50-60 degrees in my garage even in the dead of winter. Besides the slight heat savings, this makes it so the car is always comfortable to access and warms up quickly (saves gas), I can store paint and liquids in there without freezing, and it makes a comfortable workshop.

        Best $30 I ever spent!! :-)

        Reply
        • Chris November 18, 2011, 12:17 pm

          Insulating my garage (which is my workshop) door was one of the best energy-efficiency decisions I’ve made. Makes the shop usable without external heat for *most* of the winter now. (and, like you said, I don’t have to move my paints, etc to the house).

          One thing I had to do after insulating the door was readjust the door torsion springs to account for the additional weight of the insulation. (I went 2″ rigid foam board and laminated radiant barrier on top, but I’m guessing the weight is similar to R-13, in the end.) It’s fairly easy to adjust the springs, but one must be careful with garage door torsion springs… than can be quite dangerous if they let loose on you. :)

          Reply
        • John E. November 18, 2011, 4:17 pm

          Would insulating our garage door be worth the investment?

          Our attached 2 car garage is the same as any other in a 1990’s Colorado home, but the three exterior walls and the ceiling (no rooms above, just rafters) are not insulated. The back wall where the garage meets the house is insulated.

          Would you guess that $30 in door insulation would make a difference?

          Reply
          • Chris November 18, 2011, 5:56 pm

            It won’t make much difference unless you insulate the walls and ceiling too…

            Reply
        • CeridianMN November 22, 2011, 9:39 am

          Our garage has really thick doors. I believe they have insulation in-between the outer part and inner part. I think this because they are about 1.5-2″ thick. I do not know for sure as we did not build the house (it was the model for the devlopment – lots of nice upgrades from that) and are not the first owners. I am guessing that insulating those doors would not really get me much?

          Reply
  • Louise November 18, 2011, 9:33 am

    great post! I really love detailed info like this. I think trying to be as energy independent as possible is vital.

    Reply
  • Robert Heating November 18, 2011, 9:35 am

    This is chock full of really great tips to lower your heating bill. How easy is it to install a programmable thermostat? Is that something I can do myself, or should I hire someone (I have pretty limited experience, but I do learn really quickly).

    Reply
    • MMM November 28, 2011, 9:06 am

      You must replace your own thermostat, it would be quite embarrassing to hire someone to for that simple task!

      You unscrew the old one from your wall, disconnect the 2 color-coded wires from the back (or 4 or 5 if you have air conditioning too), and screw them onto the same connectors on the new thermostat. Full instructions are in the box. Done!

      Reply
    • Kimberly V January 16, 2013, 2:18 pm

      I know this was asked a long time ago, but I have to say, as a super un-handy woman who barely even touches the drill as an electric screw driver let alone any other power tools. If I can change my own thermostat (like I did 6 months ago when the old went kaput) then you can too!

      Reply
      • Gerard November 29, 2013, 8:12 am

        +1 to this. I’m such a wuss that I actually owned the programmable thermostat for several months before I had the nerve to install it, but it turned out to be super-easy. In my case, there were a couple of extra connections (for AC) that I didn’t need, but the thermostat maker’s online instruction manual covered everything for me. I’m really happy with the new thermostat, especially waking up to a warm house and better tracking my house’s indoor temperature.

        Reply
      • Emma August 16, 2016, 7:40 am

        Same here. Without technical skills I installed it in under 15 mintutes total, this includes the set-up of the app it uses.

        Reply
  • tim rapp November 18, 2011, 9:38 am

    > Using 10 insulated shutters to close second floor windows each night
    > Covering large rarely-used basement windows with removable insulated plugs

    got pics of these?

    Reply
    • MMM November 18, 2011, 10:04 am

      I added a picture of the shutters to the article for you. The plugs are just R-10 foil-coated foamboard right now, but this year I will build nice wood frames around them and cover them with fabric to make them look nice.

      Reply
      • cline November 23, 2011, 6:09 am

        Can you point out where you got your insulated shutters? When I google I come up with too much decorating stuff!

        Reply
  • Nathan Rice November 18, 2011, 10:28 am

    One thing to consider …
    A good EPA Catalytic wood stove can be operated for nearly nothing, if you consider that there is always someone on craigslist looking to get rid of a downed tree or giving away firewood. Around here, you can even find pre-split wood for about $25 per truckload.

    If your house does a good job of holding heat (following the steps in your article), then you may not even have to run the stove very often.

    Wood is a renewable resource, it’s carbon neutral (a tree absorbs as much CO2 during its lifetime as it releases when burned), and the EPA stoves produce little to no exhaust by actually burning the smoke in an afterburner chamber.

    Reply
    • Travoid December 19, 2011, 12:12 pm

      My mum’s place runs on a high efficiency wood/electric (she maybe uses the electric part for a few days per season). The heat that comes through is amazing, and it’s not that expensive to get the wood. The added bonus that appeals to our caveman side is the fact that you get to play with fire! I added a humidifier to my gas furnace, so I have the humidity a bit higher, and can then have my furnace set to 65. It feels like it is a little warmer, and we save some $ in heating costs.

      Reply
  • Marcia @Frugal Healthy Simple November 18, 2011, 11:28 am

    I like this post! We’ve got a tiny 1100 sf house that would get pretty cold in the winter when we first bought it. Well, cold for So. Cal. It had a single wall based gas heater in the center of the house (2-sided – one side to the living room, the other to the hall).

    We upgraded to central heat (house already had central air). Then we blew in insulation in the walls and the attic, replaced the windows with double paned. HUGE difference. We still have two leaky doors. Just this year we insulated our floors, and they are definitely warmer too. We have one large south facing window that’s a big help in the winter too.

    Reply
    • MMM November 18, 2011, 6:43 pm

      And with a newer and well-insulated house, Southern California is a definite example of a place where nobody should need heat, ever. A candle or a computer monitor would be enough to take the chill off ;-)

      Reply
      • Marcia @Frugal Healthy Simple November 23, 2011, 12:09 pm

        Well, it’s a 1947 built house, so it doesn’t fall into the “newer” category. But we’re working on it!

        Reply
  • mrs. g November 18, 2011, 11:42 am

    I live in FL. Heating is not so much of a problem here. Would the insulation in the attic help my house stay cooler in the summer?

    Reply
    • MMM November 18, 2011, 6:42 pm

      Yes, it sure would! The sun is almost directly overhead in Florida in the summer, meaning more of its radiant heat hits your roof and less hits the walls. So attic insulation is very important and a Florida attic should be insulated to the hilt.

      Most of the high A/C bills in coastal Florida are caused by poor insulation, since the actual temperature is not that high due to the ocean (average high in Miami in the hottest month is only 89F, meaning you only have to cool your house by 9F most of the time to remain a comfortable 80F inside and get the dehumidifying benefits of the AC as well.).

      Reply
  • BDub November 18, 2011, 11:54 am

    I love the idea of heating bill reduction but I am attacking in a different place: at work.

    I work in a semiconductor fab, and we use about 2000therms/day compared to the 1000therms/yr used in the average home. Our annual bill isn’t $960;it is $700,000.

    So, instead of spending a couple hours a week trying to get my gas bill down from $1100 to $400, I have volunteered for a heat recovery project at work that will reduce our factory utility bill by $260000/yr.

    Overall, this is much better for the planet and, in the long run, much better for personal balance sheet!

    Reply
    • qhartman November 18, 2011, 11:57 am

      So, are you getting a cut of the savings?

      Reply
      • BDub November 18, 2011, 3:20 pm

        Yep. That’s one way my personal balance sheet is improving from this project!

        Reply
    • JCH December 29, 2011, 9:39 pm

      Hi BDub,

      Brilliant idea! Would love any info/links you might be able to share about how you are approaching this process. This is something I want to do too, as it’s a huge win-win-win. (the third one is for the planet :-)

      You can email me directly if too much to post here: jhnjg aht yahoo dot com

      Thanks so much.

      Reply
  • Rolf November 18, 2011, 11:59 am

    Our homes are incredibly energy hungry!

    First off, building them is incredibly expensive and time consuming. Then they are most often shaped like buildings from the viking age when they did not even have chimneys!

    What we need is energy efficient and cheap to produce homes with no need for infrastructure like electricity, plumbing etc. Self sufficient homes with quality living is what I want to see.

    Enter Mr Buckminster Fuller with the dome and eco-home.. If I ever are to build my own home, it will probably be based on a dome. I will make sure I have south facing windows and I will build in an area with favourable winds.

    The rules for laying out a city was laid out by the ancients, even Vitrivius described the basics. But this is now forgotten by current architects and developers!

    Best tip for winter heating.. Produce your own firewood and build a masonry heater. I still dont have the masonry heater, but I do have the firewood from my own forest.

    Reply
    • qhartman November 18, 2011, 12:08 pm

      As theoretically beneficial as domes are, they do have some practical drawbacks. Most notably, even modern ones seem to have problems with leaking. Between the massive number of joints and the geometry, they tend to be somewhat more susceptible to leaks caused by material expansion and contraction during temperature changes. I’ve looked at a couple of them over the years, and every single one had evidence of water infiltration.

      If that could be affordably mitigated, they might be worth it. However, I still think you’d end up net ahead building something “from the viking age” using natural building techniques. It will be cheaper, and just (if not more) efficient.

      When it comes to masonry heaters though, we are on the same page. Those things are awesome. Some friends of mine build them for a living. You can see more about them at http://www.firespeaking.com/

      Reply
      • Chris November 18, 2011, 12:35 pm

        Another (potentially huge) downside of dome houses is that they are incredibly hard to sell (at least in the United States). The potential market of buyers for a dome house is pretty small…

        Reply
      • Rolf November 18, 2011, 5:02 pm

        Leaks is a design issue for Dome homes which have been solved.
        The early domes or poorly designed domes have this flaw.

        Resale value is not as good as a traditional house, but material usage, working hours and other investments should reflect this.
        Add more energy efficiency, maximizing volume vs materials used, reduced need for lighting, reduced risk of wind damage, internal air circulation and all the other benefits and the dome is a good choice.

        Of course domes also have downsides like the audio dispersing issue, natural ventilation, need for custom furniture etc.

        The future needs alternative thinking. The dome is one of these things. Reading about some of Buckminsters works like the Dymaxion home is very inspirational.

        What is for sure is that energy will only become more expensive in the future. Burning non renewal resources for heating will have rising costs.
        Firewood and energy efficient buildings is what we need to consider.

        Spaceship earth anyone? :-)

        Reply
  • Des November 18, 2011, 12:30 pm

    This is one of the BEST blog posts I’ve ever seen anywhere. Its like Amy Dacyczyn meets Jacob Fisker.

    Reply
  • Brian M. November 18, 2011, 12:31 pm

    For anyone interested in Passive Solar design, I’d recommend “The Solar House: Passive Heating and Cooling” by Daniel Chiras. It’s got a lot of great ideas based on the author’s experiences living in multiple passive solar homes.

    Reply
    • Joe Average July 28, 2015, 9:08 am

      I once fell in love with a passive heating home. It had an outer and inner structure that created natural drafts to heat and cool the home. The owner pointed out they could potentially create a problem were it ever to catch on fire. I mentally backed away from the design and then later decided I would reconsider it if the house had more concrete and stone and less wood. Unintended consequences.

      Reply
  • Susan V November 18, 2011, 12:35 pm

    To add to the discussion on retaining heat lost through windows: I have almost all western facing windows (only 3 southern facing in the entire house!). You’ve insulated the walls, but the windows are now the major egress for heat. For windows where it doesn’t matter or if you’re renting and don’t care, put batted insulation in there and close the (insulated) drapes. If you want fashion, I’m making my own insulated roman shades and using this from the local fabric store: http://www.warmcompany.com/wwpage.html
    It’s a multi-layered fabric with mylar and insulative layers. You add a decorative cover fabric and custom build the hardware /shades (basic carpentry and sewing skills). The shades then adhere to the sides of the windows with a magnet, creating an insulating space between the room and the window. Decreases heat loss in winter, blocks heat in summer. For your southern facing windows, you can raise the shade during the day to heat the room, then lower the shade at night (or on a cloudy day) to retain heat in the house.

    The fabric retails for $28/yd where I live, but I bought it on a half off sale & had a coupon so my cost was more like $10/yd. I already had the decorative fabric since I was planning to make my own drapes. I just changed the approach. I’m in the process of making them now, but if they live up to their hype, my rooms will be warmer and look good. In the past, we’d hung a rug over windows no one saw, but it was still chilly near them. Since these sear around the window, there is less of that cold chill feeling.

    Since MMM is so crafty, I thought he and the rest of you might appreciate this DIY approach. I have nothing to do with the company, I just came across their product and thought it seemed like a great idea (much better looking than the rug method!) If anyone wants to try and calculate cost/anticipated reduction in heat loss), I’d love to see it. I just went with my gut on this one.

    Cheers!

    Reply
    • Bella February 23, 2012, 10:28 am

      Thanks for the tip – I even have a bunch of warm white in my fabric stash – and it goes on sale at Joann a lot. I have a huge picture window in a room we don’t use very often that would be a prime candidate fo this project.

      Reply
  • Brian M. November 18, 2011, 12:55 pm

    There is a lot of discussion here about insulation. Insulate the attic, get lower u windows, cover the windows with quilted covers… All great advice, but from my experience an older home can be made a LOT more comfortable with a caulking gun and some expanding foam.

    The average home has enough air leaks to equate to having a 3′ x 3′ window open all the time. I guarantee you are losing more heat from those leaks than you are from convection through your walls and ceiling.

    Things I did in my house to make a dramatic difference.

    1. Replaced old leaky windows with new one that have an air infiltration rate of < .1%
    2. Pull the casing off of your windows and doors, pull out any fiberglass between your windows/doors and the rough openings (it just filters the air for you. how nice) and shoot expanding foam in there.
    3. If you have an unfinished basement, seal up the rim joists. You can do this with spray in foam, or rigid foam board surrounded with expanding foam.
    4. Go around the outside of your house and find any penetrations where cables, pipes, whatever, goes into your house. Caulk around them.
    5. Have an blower door test done. If you don't want to pay to have one done, rig up your own blower door setup. There are youtube videos on how to do this. Take a stick of incense and walk around the house while the blower door is running to find the air leaks and seal them up, one way or another.
    6. At this point you've probably sealed up your house tight enough that you need to start looking at mechanical ventilation. This will take away some from your energy savings, but you will be breathing clean air that hasn't come in through your dirty walls, and attic.

    After you are done with all of that, _then_ start looking at insulation.

    After sealing up our house tight, we cut our heating bills in half. That was before adding any insulation.

    Reply
    • Brian M. November 18, 2011, 1:30 pm

      I forgot to mention those handy gaskets for your outlet and light switch covers. If you don’t mind something a little more permanent, you can pull off your outlet covers, run a small bead of caulk around the opening and put the plate back on, creating a seal.

      Reply
      • MMM November 18, 2011, 7:00 pm

        Thanks Brian, great addition to the article! I called your comment out in the main text because you are right, I completely skipped the details of sealing the air leaks.

        Having a company come and do an energy audit (including the blower test) is a worthwhile expenditure as well, depending on your annual heating costs, your existing level of knowledge, and any offsetting tax credits.

        For the average Northeastern US resident with a $1500+ heating oil bill, it is a very good idea. Even I might do it, so I can watch the inspector and learn from him, eventually stealing all his techniques.

        Reply
    • Dean December 17, 2013, 9:20 am

      @Brian M.

      I took off my window casings and found roughly an 1/8th of an inch gap. I cannot fit the expandable foam tube into the gap. What do you suggest instead?

      Currently, it contains fiberglass insulation but have noticed that it’s very cold to touch. I do not feel any air leaks, but have noticed that the area, in general, is a lot colder than it should be.

      Would thin slivers of foam board be appropriate? All idea’s are welcome!

      Reply
      • Brian M. December 17, 2013, 10:51 am

        @Dean

        I’d leave the fiberglass in there and caulk the gap with Acrylic Latex Caulk.

        Reply
    • Mackenzie April 23, 2015, 11:52 am

      When I bought my house the air conditioner was broken. Repairs failed, so moved on to replacement as a plan. First, though, we got an energy audit, hoping we could switch to a smaller unit.

      In my area, energy audits are 75% subsidized by the energy company, and they pay up to 50% of the cost of fixing the leakage issues, if you get at least a 20% improvement.

      Long story short, we got a 50% improvement by having the roof and the ceiling rim joists foamed along with a bit of weather stripping. We got 50% back on the cost of the insulation work. The air conditioner went from 2.5 tons to 1.5 tons. Our electric bill in August when we had only a window unit, and our electric bill the following August with the new central AC were exactly the same. Our heating bill went down $20 per month, despite increasing our night time temperature setting (we had a pipe freeze the previous winter so we set it to 62 at night instead of 52).

      Reply
    • Michael December 23, 2015, 6:10 pm

      For windows/doors, use the foam made for those applications (it doesn’t expand as much) so you don’t inadvertently squeeze the frames, making them harder to open.

      Reply
  • Steve D November 18, 2011, 1:16 pm

    I’m surprised there hasn’t been a mention of ‘spot heating,’

    I’m assuming that is much too basic for the MMM readers? But I’ve yet to turn on the heat (I’m in SE MI) this year yet (last night was 23 and breezy outside).

    Getting a small 400 to 800watt space heater keeps me warm when reading, watching TV, or right as I fall asleep. And is much more energy efficient than heating my entire 1000sq ft condo.

    It truly pains me to see friends purchase 2500sq ft homes (for a single dude) and heat that entire house! it’s incredibly wasteful and expensive

    my personal goal is “No Heat 2011” (for the rest of the year) relying on proper attire and my radiant heater. I may have to revise that to “No Heat November” depending on how bad December gets out here. Thankfully I live alone

    Reply
    • Brian M. November 18, 2011, 7:31 pm

      We “spot heat” our bedrooms at night. We have an electric resistance heater in each bedroom on thermostats. Each uses 750 watts for about a minute or so per hour. I think it’s a great idea. The only thing that might be better is zoning your HVAC system.

      Reply
      • Luke November 9, 2014, 7:25 pm

        i should not say part of this tip(the thermostat part), because some one with lack of experience will try it and get hurt. but if you run a 400 watt space heater.. wire an outlet to run off a old thermostat and then set a 19$ wall mart box fan in front of the heater and receive a very robust flow of heat.. if you do not know how to wire an outlet to run off a thermostat, do not try it! just plug the fan in and let it run on low in front of your heater. but it is much nicer to have the fan and heater both turn on and off by the thermostat controlled outlet

        Reply
    • Belcat January 31, 2012, 2:00 pm

      Also consider an electric blanket. I’ve usually found it actually provides way more heat than I need, and I have it auto-shutoff after an hour.

      Reply
  • sumarie November 18, 2011, 3:15 pm

    What about moisture build-up? We live in northern Minnesota where
    the winter humidity is low, but wouldn’t we have more moisture problems if
    we were to insulate & take the above-mentioned steps to tighten up our
    house?

    Reply
    • Brian M. November 18, 2011, 3:34 pm

      As long as you have a good bathroom vent that exhausts out your roof and not into the attic, you should be fine. If you get the house to the point where you need mechanical ventilation, the HRV/ERV should also help exhaust any humidity. You can set the HRV up to have positive pressure by baffling the exhaust some. This will draw in more air than it lets out effectively not allowing any outside humidity in. If it’s still a problem a whole house de-humidifier might be in order.

      We have not had any humidity problems in our house even after tightening it up so much.

      Reply
      • Brian November 19, 2011, 10:10 pm

        Sure, but the cost of an ERV/HRV is going to wipe out years of savings since they cost $1500 just for the unit ($2500 installed) + annual filter replacements.

        Reply
  • Gerard November 18, 2011, 3:27 pm

    MMM, seems like this is one case where the benefits of your past Mustachian choices actually work against your current Mustachian goal of heating bill destruction. You’re warmth-loving people spending many hours per day in a large house not expressly designed for heating efficiency. Obviously a sun-aligned smaller house with a big “backpack” (building all storage, hallway/stairway, and little-used spaces on the cold side of the house, so that they act as feet-thick dead air) would create instant badassity here.
    Still, it’s pretty damn amazing that you can get your energy consumption down that low. Some of the suggestions I’ve read won’t work for me (where I live we don’t have winter sun), but I’m definitely on that foil-wrapped insulation in the windows.

    Reply
    • MMM November 19, 2011, 10:46 am

      I agree, my house is fairly non-Mustachian in many ways. I bought it five years before MMM was born, and my luxury desires have lowered quite a bit since then. On the plus side, it pays for itself by making a nice vacation rental for other people when we go on long trips.

      But we will still eventually downsize once we have a grown boy – or maybe earlier, if the hobby of renovating other houses in this neighbourhood eventually leads to a purchase of a nice South-facing place even closer to the school and other amenities.

      Reply
      • Belcat February 3, 2012, 11:44 am

        Hey MMM, I am a little surprised how much you put in renovating for energy saving, but as a green person I am totally for it.
        You might want to look at Passivhaus, sounds like it’s what you would like to have been able to do. In the middle of winter, in Saskatchewan, they had a house requiring no heat.
        http://en.wikipedia.org/wiki/Passive_house
        http://thetyee.ca/News/2011/01/25/Passivhaus/

        Do you realize we knew of this 34 years ago? There would be no energy crisis… maybe an insulation crisis :P

        Reply
  • Iowa November 18, 2011, 6:22 pm

    The placement of the thermostat is also important. For example, mine is in the master bedroom where us two inhabitants sleep and for a hour or so each night before sleep the door is shut and it delays the heater from kicking again for quite some time. May not work as well for others in the home, if there are any. But, hell, you may not care either.

    Another thing I’ll add here for those who get snow in the winter. Shovel some against your foundation. Those eskimos know what they’re talkin about when they built homes from snow/ice. My dog appreciates it when I cover her house up with snow too- only because she enjoys the snow flying. But she stays warmer as well.

    And lastly, close the damn doors/vents to those rooms you don’t use.

    One last thing; I enjoy the lack of censorship this post will recieve in regards to the swearing. Shit, damn.

    ………..and one last thing. Bring a cup of hot chocolate to the old lady when she complains about the temperature. Special attention recieves special thanks and leniency. Might even result in actually increasing the bedroom temperature…too far?

    Reply
  • anonymous November 19, 2011, 1:35 am

    with insulation and energy efficiency, be careful of trapping indoor air pollution, and specifically radon gas. Radon gas levels can build up even in houses that sit on a concrete slab.

    Reply
    • Belcat February 3, 2012, 11:21 am

      Often Heat Recovery Ventilators are added to keep the air from getting stale as well as get rid of Radon. The fresh air is a nice luxury. We had to install one because we were getting condensation on the windows.
      They are a little costly to install, but certainly more cost saving than letting air leak into your house, or opening a window.

      Reply
  • Heather November 19, 2011, 7:48 am

    Last year we recently installed a wood fired water heater. Based on what we were spending on heating our old farm house (we have new windows, added lots of insulation, but still drafty), our pay off time will be 2 to 2.5 years. We were spending $3,000+ on heating oil, but have local tree removal service bring in the fire wood for us for free. My husband figured he was saving $15 each time he went outside to put some wood in the heater.

    Reply
  • chrm November 19, 2011, 12:12 pm

    Here is something I think you will find very interesting M3. It’s called a “rocket stove mass heater”. It’s a combination of a clean and efficient combustion and the thermal mass, you are so fond of.

    http://www.richsoil.com/rocket-stove-mass-heater.jsp

    http://transitionculture.org/2006/03/10/top-five-things-to-do-with-oil-barrels-when-theres-no-more-oil-to-fill-them-4-build-a-rocket-stove/

    Reply
  • bmf136 November 19, 2011, 9:21 pm

    Another great article, MMM! I live in Jupiter in sunny South Florida where heat is plentiful and south facing windows aren’t all that desirable. I’m fortunate that we live. In a 3 story townhouse with windows facing the north, east, and west. This is good for our area since we avoid the harsh sun exposure that would force us to run the air conditioner mor. In the winter our cool fronts bring winds out of the north, east, or west. Having multiple levels makes it really safe to leave the windows open to cool our place free of charge!

    When our building was being built we would walk through all of the other units in our building and ours was always the coolest because of how the sun hits the building and the alailable breeze. The end unit on the opposite end of the building was by far the hottest…yuck! We picked up a very Moustachian townhouse!

    Thank you coevally of the great blog posts!

    Reply
  • bmf136 November 19, 2011, 9:25 pm

    Ugh! Auto correct on my (free) tablet…

    Last sentence should read, “thank you for all of the great blog posts! ”

    I’m still getting used to this device…

    Reply
  • Retired Rob (Did it by 35) November 20, 2011, 6:02 am

    I might have a solution for you to completely get rid of your heating bill. Take a moment and google “Solar Furnace” There are many videos, so be prepared to watch a few to learn how they work. Basically, using the power of the sun and a little DIY effort, you can make a solar furnace powerd by the sun. Even the fan can run on the solar power so there is zero cost to operate, just the initial materials to build it.

    I am planning to build one this winter to try it out (I am from Ontario). I have a south facing wall in my garage and I will use a window rather than punch a hole in the wall (for now). Once I test it, and am satisfied that it works, I have plans to pump the heat into the house. I’ve seen the videos numurous times and have never seen one in action until I went for a walk the other day on one of the local Universities trails and I came across one of the ‘eco buildings’ they build on the property for the environmental program. It has solar hot water units on the roof, solar panels on the roof, as well as 4 solar furnaces on the south wall. From a distance, I actually thought they were shutters as they installed them on either side of the two large south facing windows.

    Again, just search “solar furnace”. In fact, you’ll find many other DIY solar options for heating your hot water, heating your home, heating your pool, etc. I’ve wanted to try these out, and now I have the time.

    Thanks and great site BTW.

    Rob

    Reply
  • Kyle November 20, 2011, 12:24 pm

    I saw a couple people mention spot heating. Paul Wheaton of Permies.com used spot heating to reduce his heating bill by 87% last winter in Montana.

    http://www.richsoil.com/electric-heat.jsp

    I also heard a pretty interesting idea to reduce A/C costs. It might have also been from Paul Wheaton. You put a soaker hose up on your roof and have it turn on for a few minutes every hour or so. It cools down your shingles and uses evaporative cooling. If you cool down your roof, you cool down your attic, and thus your house. Here is an article about the concept: http://www.builditsolar.com/Experimental/RoofCooling.htm

    I also had a questions regarding radiant barriers for the attic. Are they bad to have up in the winter in a cold climate? Will this reduce heat gain from the sun?

    Reply
    • MMM November 20, 2011, 5:06 pm

      Yeah, Paul Wheaton is a neat guy and I highly support his natural way of doing things. MMM is a little different in its focus, because I’m trying to describe ways to lead a US-style middle-class life with kid(s) that happens to be 50-75% cheaper and less energy-intensive than normal. So that still leaves a lot of consumption and the luxury of heating your whole house all at once.

      Once people get to this level, they will really enjoy it and start trying to find ways to go further, as I find is slowly happening to me. But if you take someone who is currently in consumer debt, and show them a picture of a desk with a blanket hanging over it and a little electric space heater underneath, I think it will blow their mind and they won’t even feel like getting started.

      If I lived alone, I’d be all over the 50-degree-house. But with gentler creatures sharing the home, I am quite happy to keep them warm and have the privilege of seeing their bare feet at a monetary cost that works out to about one hard day’s worth of labor per year.

      Reply
  • Co November 20, 2011, 8:01 pm

    What about on demand water heaters to lower hot water costs? We have a tank and pipes that are insulted but will probably have to replace soon so have been looking into this option.

    Reply
    • MMM November 21, 2011, 7:20 am

      They definitely do lower costs! Both through lower standby heat losses, and through higher efficiency when they are running (90% or more vs. 60% or less).

      I figured out that switching to an on-demand one myself would save me $60-$80 per year. So it is worth paying $600-$800 extra for one according to my own desire for return on investment. At the local Home Depot, I noticed that a standard tank one is about $400, and a tankless is $999. But in the US there is also a 30% federal tax credit, lowering the net cost of the tankless heater to only $700. At a $300 price premium, this is a great deal, and it takes up less space in your house as well.

      The only hitch is in the installation. Some plumbers I know like to charge a thousand dollars more to install a tankless heater, despite the fact that it only takes a few hours of extra work compared to a standard one. So be sure to compare the total installed cost if you won’t be doing your own installation.

      If the tankless option does not pan out, you can approximate the same savings by adding a thick insulation blanked around a standard tank water heater, and using a lower-flow showerhead like this one for 10 bucks: http://www.amazon.com/gp/product/B003UQ17O4/ref=ox_sc_act_title_1?ie=UTF8&m=A1RGMBJOXFAIVA

      Switching to a showerhead like that one in a multi-person family will actually save almost as much annually as the tankless heater. Even more if you have electric or heating-oil-heated water. I am about to make the switch myself – hopefully the reviews are right and the reduced water flow doesn’t cut out the fun of showers too much.

      Reply
      • Bakari November 21, 2011, 8:50 pm

        I found an ebay seller of instant water heaters (both propane and LNG). The size I needed was under $100, but of course my home is unusally small and light and water use. So called “whole-house” multiple bathroom models run $300-$500.
        All brand new, with “buy-it-now” pricing (no bidding).
        (Still, I waited until my old tank heater started leaking before I upgraded)

        They are SUPER easy to install – bolt to the wall, attach two water lines and one gas line (or plug it in), done. One person, a wrench, and ten minutes (for a handyman, maybe an hour for a novice)

        The best part is that you can actually take infinitely long showers, while at the same time actually saving money overall.

        Reply
      • Jeff November 22, 2011, 9:55 am

        You can’t assume a 10% ROI on everything. Many things don’t last 10 years. And if you have to fix them, that throws off your calculations.

        Reply
        • MMM November 22, 2011, 10:46 am

          Hmm.. maybe you could suggest a better return-on-investment I should be targeting for my energy saving purchases?

          For things that last much longer and keep up with inflation (like dividend-paying stocks or rental houses), I am happy with 5% positive cashflow per year. For things that eventually wear out, like a tankless water heater, compact fluorescent light bulbs, or solar panels, I go for something more like (5% + annual loss-of-life of the item). So that would be 15% for an item that lasts 10 years. Luckily, most of the returns of the things we’re talking about (like insulation and efficient bulbs) are far above 15% per year, allowing us to skip the detailed math.

          A Nissan Leaf, on the other hand, requires some very detailed calculations if you are hoping to save money by buying one, because you have to trade off the effects of tying up a huge amount of money ($30k) in a depreciating vehicle, vs. a large annual savings in fuel costs.. vs. your own feelings on how much you hate burning fossil fuels, vs. tax credits and how much you like (or dislike) getting them.

          As for expected maintenance, that is also on a case-by-case basis. It it is something I don’t enjoy working on, like replacing an asphalt shingle roof or an underground sewer pipe, I budget a high amount to account for maintenance. If it is just pleasant tinkering in the garage, like replacing spark plugs or adjusting with temperature-controlled valves in my future solar water heating system, I consider that part of my education/leisure time so I don’t have to pay myself as much for it.

          Reply
          • Jeff November 28, 2011, 11:24 am

            I suppose my comment is that there’s a difference between a return on INVESTMENT and return on EXPENDITURE. A dividend on a stock is different than savings on a tankless water heater because you assume that the stock is more or less worth the same amount of money at the end of ten years. After 10 years your water heater may still work for a little while, but it’s not worth anything and anyone considering buying your home will assume it needs to be replaced. With a 10% return, you’re talking about making back your money after 10 years. In other words, it will be 10 years before you see a savings on your purchase. Hopefully you don’t move before then.

            So, no I can’t really suggest a better method than a case-by-case basis because it really is going to require that, and I don’t think that’s unreasonable when you’re considering hundreds of dollars for a more efficient appliance. One thing to consider (which makes the numbers better) is the idea that you will eventually need to replace your water heater, so the real expenditure is the difference in price between a standard appliance and the high efficiency appliance.

            Reply
      • abc November 22, 2011, 9:30 pm

        Hi MMM,

        Long time reader, first time commenter. Just want to say I appreciate your spreading the mustachian way! I lived and studied in Berkeley CA and many of your principles are practiced widely there– for better and worse, to be brutally honest. Additionally I was raised by two of the most frugal and self reliant people you’ve ever laid eyes on, so many of your mustachian principles have simply been second nature my entire life. I have read all the entries (and all the comments. phew) and thus far managed to refrain from wading in. However, the subject of shower-heads is a critical one, and I really feel I would be doing you a personal disservice (yes, personal!) not to direct you to this beauty:

        http://www.amazon.com/Interbath-All-Directional-Chrome-Showerhead/dp/B000HQV8BC

        I’ve had the same one going on 15 years now, no plastic restrictor, and I just now measured it at an average 5L/min, or GPM of 1.32 for a really satisfying shower. Also very useful for tall people.

        Reply
        • MMM November 22, 2011, 10:19 pm

          Thanks Alphabet!

          I actually just changed my master bathroom’s showerhead from the stock 2.5GPM one to a 1.5GPM one that I found on sale for $9 at Home Depot (there’s also a good one at Amazon here: http://www.amazon.com/gp/product/B003UQ17O4/ref=ox_sc_act_title_1?ie=UTF8&m=A1RGMBJOXFAIVA

          I calculated that a change like this should save about $50 per year in a one-man-one-woman household, and more as you add additional women ;-)

          I’m surprised that the showerhead you listed is a low-flow one, since it is not listed as such. I would be careful in recommending that to others without the rating, because the flow rate on an uncontrolled showerhead depends strongly on the water pressure. But thanks for the tip and huge thanks for being such a dedicated reader.

          Reply
  • Bakari November 21, 2011, 8:59 pm

    Inspired by your post on thermal mass, I recently brought all of my emergency water indoors (15 gallons, in case of a natural disaster that cuts off the municipal supply).
    I move them in front of the window in the morning when I open the curtains.

    Combined with adding plastic wrap to all the windows, opening the south curtains in the day and closing them at night, and wearing layers and a hat and jacket, I’ve gone so far this season with no extra heating at all (granted, I live in Northern CA, not CO, but it has been pretty cold outside by CA standards).

    Assuming I make it, this will be the first full season I go w/o heat (I did it the last half of last winter)

    Reply
  • mathx November 22, 2011, 9:14 pm

    How to REALLY destroy your home heating bill. Dont heat the home, HEAT YOURSELF:

    http://www.richsoil.com/electric-heat.jsp

    not sure if this is practical, but I think of this quite alot as during the day when my wife is out and Im working at home (MMM-style self 3/4-time employed!) Im upstairs in a small office (chosen small on purpose, I dont need/want alot of space for an office, ill just spread out!) – i turn the heat in the house down to 65F, and close the bedrooms and their vents (and blinds and curtains, tho they dont seal the window air-pressure wise like a real MMM seal…)) and hope the heat mostly rises up to me – my computer being bloody 130W and monitor being 40W (and UPS being 9W and cordless phone is 8W…) the room stays fairly warm, but I also wear a giant fleece.

    I cant really let it go below 65F downstairs or it gets pretty cold upstairs. My feet get really cold tho I wear thick outdoorsy wool socks. However, I remember the days of my C64 which had a big power wart on the floor I used to keep my feet on :) Maybe I should vent my computer onto my feet somehow… :) My hands getting cold is annoying, when the backs are cold, it’s just distracting, and is a tangible long term stress on you while working. Just one more thing to distract from work, and the human body will make you do something about it.

    I notice that a laptop actually on your lap makes you really godamn hot, even when it’s only dumping 20-30W of heat out – those big fat blood vessels on your legs – often used to cool humans when walking around in summer – absorb alot of heat, and I can sit in a tshirt. But working right on my lap with a laptop is not very comfortable. I prefer a desktop and a desk…

    However, im getting a standup desk going soon, so perhaps that dog warming pad for my feet and a heated keyboard for my hands is good. Face being cold, not sure about that. That might be more easily tolerated (seeing as humans sleep with their faces out even in pretty cold environments – and we walk around like that too, and we’re only talking 50-60F, not 20-30 (and I’ve camped many times with my head out entirely in a 40-50F indoor (keychain thermometer) tent, and with a toque on in 35-45F…)

    Anyone else looking at heating themselves not their house?

    Reply
    • qhartman November 23, 2011, 9:01 am

      I do this at home when the wife and kid aren’t around, or I have to go into the office at odd hours. I’ve found that a small 500-ish watt space heater tucked under my desk makes a WORLD of difference for cold feet and hands. I have it set so it only kicks on for a few minutes each hour, about 1 minute every 15 minutes, so at my electricity rates it costs about $.002 per hour to run. WELL worth it for the increase in comfort

      Reply
    • Amicable Skeptic December 26, 2011, 4:31 pm

      I do something very similar when I’m working from home and my wife is off at school. I drop the house heat down to 58 then go up to my office and shove a foam pad under the door (thinking about weatherstripping it as well). The heat from my monitor and laptop keep it near 70 in the office and if I get really cold I have a lamp with a a few old incandescent bulbs in it that I turn on and set right next to me. Incandescent bulbs do work as super cheap space heaters as long as you position them really close to yourself (they lack circulating fans like real space heaters so setting them up in a corner a few feet away from you is not so efficient) and they also help brighten up my dreary upstate NY winters (I use CFLs for all my other standard sized bulbs though, cause incandescents for non-heating are not very mustachian).

      Reply
    • Belcat February 3, 2012, 11:14 am

      You can get one of the pads they recommend for sticking on the bottom of aquariums to keep the reptiles warm. They are safe to stick to anything so long as one side isn’t covered. This helped keep my feet warm.. and the pads don’t use that much energy neither. They also have (at dealextreme.com) some slippers with USB heating pads in them, they are actually TOO warm, they use about 2.5W.

      I actually used a 12V pad recommended for keeping water tanks warm and hooked it up to the USB (it used 5W this way with the lower voltage)… but that is too hacker for most people.

      Reply
      • kathryn June 19, 2014, 9:26 am

        I have also used a hot water bottle, sitting on my lap..when making a cup of coffee, use the rest to fill the HW bottle.

        if you don’t have a HW bottle, any bottle with a tight fitting lid will do.

        Reply
  • Brk December 2, 2011, 8:07 am

    Just a quick curious side question about the batts you used to insulate your garage door: I notice they are faced with the kraft paper lining; are you not worried about the flammability issues with having that exposed? I know, I don’t have lots of open flames in that area either, but just curious as most exposed insulation paper like that usually gets covered up by drywall.

    I love the idea of just using regular batts though. I see the pink panther foam blocks they sell @ big orange and they are way too pricey for the amount you get.

    Reply
  • Christine Stamper December 5, 2011, 10:53 am

    THE HOME ENERGY DIET
    By Paul Scheckel

    Best book ever for this topic. Buy it, read it, understand it, act on it. I’ve been able to cut my nat gas usage over 50%, and this book helped greatly. It explains the scientific principles, the calculations and the fixes in terms that a non-technical do it yourselfer (aka: the lay person) can understand. Check it out on Amazon. (I have no financial interest in this book. I do not know the author. I am just a big fan)

    Reply
    • Gina December 31, 2015, 2:53 pm

      Thanks for the recommendation. I looked at it and it gives way more information than many home efficiency books.

      Reply
  • Jake December 5, 2011, 7:03 pm

    Turning down your thermostat by ten degrees in the winter is equivalent to moving from philadelphia to Dallas.

    Check out average temps for yourself.

    Reply
  • Platypus February 18, 2012, 6:42 pm

    For those of us playing at home in the Southern hemisphere, remember to swap the recommended south-facing windows to north-facing windows. If you are buying, try to find a block/house where the long side is north/south rather than east/west and let the nature help you out with passive solar heating and optimal air flow.

    Reply
  • anonymous June 24, 2012, 5:25 am

    Random thought: does any fundamental reason exist why a clothes dryer couldn’t exhaust its heat *inside* the house? The exhaust typically includes some lint, but a simple cleanable screen would solve that problem. And then, rather than having a pile of wasted heat dumped outside, you’d have a pile of useful heat dumped *inside*.

    Reply
    • Stephane Boisjoli June 25, 2012, 9:35 am

      There are kits for it; they use water to attempt to reduce the dust from the lint that goes flying all over. You have to realise a simple metal mesh screen won’t trap all of it. And anything with more filtering power may clog up too fast and cause a fire hazard – the air MUST be able to move, or the dryer will build up too much heat and may catch fire.
      But yes, it can be done, if you don’t mind the extra dust and the extra humidity (which may or may not be a problem depending on how humid your house is).

      Reply
      • Steve January 1, 2013, 3:22 am

        I bet vacuuming technology could be designed to solve the problem. They are made to do exactly that, separate dust from incoming air and blow the air out through a filter.

        Reply
    • Mr. Money Mustache June 27, 2012, 3:32 pm

      Yeah – I’ve always vented dryers to the indoors during the heating season (although nowadays I never use the dryer anyway). I found the best filter is simply an old pillowcase duct-taped around the end of the vent hose. That filters even the finer lint particles, leaving only clean humid air for your house.

      Just be sure to set the end of the hose to blow somewhere that you actually want the humidity. Into an open room or hallway – not into a tiny laundry closet or the little space between your dryer and the back wall.

      Reply
      • Stephane Boisjoli July 14, 2012, 1:21 pm

        There’s no way a pillowcase filters all the lint, but at least it has a pretty big surface area, so it will take some time to clog up (and so the risk of fire is minimized).
        I’m pretty sure clothes lint comes in all size, some of which makes it through the pillowcase. The only way I can think to check it would be to use some of those really good furnace filters and force the dryer exhaust to go through the filter. After a while you will be able to see what is left … it would take some runs since these are small particles and we don’t see them until they accumulate.

        Reply
      • Jad D. March 3, 2017, 1:35 pm

        I’ve been using a dryer vent diverter for a couple years. You can get one on Amazon for $10, or at Ace Hardware. It has one moving part: a simple flap diverts the heat and humidity into the room in the winter; close the flap in the summer to divert the exhaust air outside. It doesn’t include any water reservoir, just a clean-able lint screen.

        Two important things to note: one, these are not sanctioned by mechanical codes, and two, never use one of these on a gas-powered dryer.

        Reply
    • babar October 26, 2012, 10:09 am

      So long as it’s an electric dryer and humidity isn’t an issue, you’re set. Gas dryers HAVE to vent outside, because they exhaust gasses as well like carbon monoxide.

      Reply
  • superbien July 2, 2012, 5:58 pm

    I’m smiling to myself because everything you’re talking about as “econ” is what I’ve been learning as “eco” — it’s what I’ve been studying in my green building classes, and learning about in my internship with a green construction company. Insulation above all else, passive solar as the second major element. But you’re right – the savings element (money, fossil fuels) is one of the most elemental reasons to go green, thanks for doing the math side of this calculation!

    When you look into the next house, some other things to look into: earth berming – you might read a book by Rob Roy (not that one) called “Earth Sheltered Houses”, you can often earth berm an existing house so long as you reinforce the structure for the extra weight — and radiant flooring, which use miniscule amounts of heat (something like a lightbulb) but allow you to reduce the heat big-time – my parents have them and it makes such a difference in their always-cold house. Oh, if you build your own house instead of retrofit, I love clerestories (little high-up windows for the non-South windows to add sunlight without a lot of heat).

    Lastly, if you don’t already read Mother Earth News, I think you’d really dig it. They’re smart people with a similar mindset as you.

    Reply
  • khitchens October 2, 2012, 7:44 am

    Surprisingly enough, no one has mentioned Geothermal heat, that can also tie into your water heater.

    I switched to geothermal a few years ago, and saw my energy bill cut by about half.

    Start up is costly, and the install is as if WW3 hit your back yard, but once done, it is awsome!

    Reply
  • brenda from ar October 28, 2012, 9:40 pm

    I vent my electric dryer into an old pair of hosiery. If it gets a fair amount of lint in it, change to a new pair. As a side trick, this is a good time to clear excess lint from the wall vent. Mine is maybe 12 feet from the exterior. My method: shove leaf blower into vent behind dryer, wrap a towel around opening to block air flow, turn on leaf blower, presto – clean vent. Then I stuff something in the wall vent to help block cold air from entering the house.

    I keep some rooms blocked, use a tiny ceramic heater in the bathroom which also helps the bedroom, and keep the remainder of the house coolish (62-66). Putting an old pillow under my feet under my desk really helps too.

    This article and the comments are a fabulous resource.

    Reply
  • Erica W January 12, 2013, 12:50 am

    My mother managed without AC all summer by opening and shutting both drapes and windows at appropriate parts of the day; closed drapes at dusk in winter too, when she has the option (as much for privacy as for heat, but it does both).
    I wonder how much the energy savings actually pays off in money?
    Energy costs are rising, so these little labors of love will obviously become more valuable over time. But if it takes you say, 15 minutes to go around a large home and open all the drapes, then another 15 later on to shut them again, are you paying yourself enough in energy savings to make these 15 hours per month worthwhile financially as well as on principle?
    (Of course, along the same lines as 20 push-ups, taking a short daily walk around your house might also be saving you the cost of a gym membership…not to mention helping you notice any other little maintenance problems before they become expensive damages.)

    Reply
  • Kyle February 13, 2013, 10:14 am

    I love the clarity of the explanation but now I’m somewhat confused on what action I should take. We have an East/West facing house (in VA) with one small hallway window on the south side. The windows were recently replaced however I don’t have the u-factor information on hand (~17 normal sized and 3 smaller windows). We close all our wooden blinds at night and I was previously opening them during the day thinking that the sunrise/sunset was giving some heat benefit as well using the daylight to eliminate the need for a bunch of interior lights to be used during the day. Would it be better to keep the blinds shut during the day and use the interior lights (CFL with some Halogen) to benefit from the heat savings? You’ve made the point that electricity is more expensive than gas so I’m assuming the answer to my question is no. Thanks for giving me more information to mull over.

    Reply
  • bob werner September 17, 2013, 7:54 am

    You would be a perfect tester for converting a chest freezer to a fridge. Your annual electric savings wouuld be around $200, or $3,000 in 10 years. It will also move you closer to a solar independent lifestyle and be a great column and use of your skills in building. Source a freezer on craiigs list and sell your fridge for zero up front cost. By the way, much as you refer to car users as clowns, off griders refer to you as MrGrid Clown. http://www.aselfsufficientlife.com/chest-freezer-to-fridge-conversion-the-most-energy-efficient-fridge-ever.html or

    Reply
    • Mr. Money Mustache September 17, 2013, 8:51 am

      Great suggestion! Chest fridge conversions are a really neat invention. Note that your savings are a bit off (my giant double-door fridge with icemaker uses 564 kWh/year, costing me $56 in wind-generated electricity), but even so, a chest fridge would easily outperform it.

      Especially useful for people who have room for that in their current kitchen layout, or who are designing kitchens from scratch to accommodate the different shape.

      Reply
  • Brendan October 10, 2013, 2:16 pm

    It used to be hard to find windows in the US that had a high SHGC. A year after I replaced the windows in my house Pella came out with a “NaturalSun” glass option that has > .5 SHGC and about .3 U value. Wish I had those on the south side of my house. MMM you may want to look for something similar for your upcoming remodel.

    Reply
    • Mr. Money Mustache October 10, 2013, 10:27 pm

      Thanks Brendan, I will definitely look for windows with comparable stats – I’m just about to start researching the window options, and I didn’t even realize I could get windows with a 0.5 solar heat gain coefficient.

      Reply
      • Dean January 19, 2014, 6:10 am

        You can also look into Harvey windows. We got our triple panes with a 0.23 U-factor. They work so well that the plants we put in front of them began to die. We had to move them under a UV light to keep them alive.

        Reply
  • tintin October 25, 2013, 1:09 pm

    Attic hatches are another area to look at insulating. I have a large hatch with a ladder attached. It doesnt appear to be sealed at all. I am trying to figure out the best way seal the hatch as tight as possible and allow access.

    Being in the surburbs of Toronto Canada, there is another scam people should be aware of : rental water heaters. I have heard that renting water heaters is only popular in Ontario

    We moved into a new house and as part of the purchase agreement, we assumed the rental of the water heater from the old owner. Big mistake. I am being jacked each month on my heating bill for the rental of a tankless unit for about 30 bucks a month. This is a lesson learned. Never assume the rental of a water heater. Get the seller to eat the cost and buy it outright.

    I am sure MMM would punch me in the head for this whopper. And I would deserve it.

    Reply
    • Buzz March 20, 2016, 9:19 pm

      There is a company called Battic (I have no financial ties to or interest in the company) that sells an attic stairs insulation cover with R-50 insulation. It’s more or less a styrofoam box with heavy insulation on top that fits precisely over your attic stairs, and it very tight as well as easily movable whenever you want access to the attic. My wife and I purchased one and it has made a major difference both in cold and hot weather in sealing off unwanted air exchange.

      Reply
  • Bethany November 13, 2013, 2:23 pm

    3 big windows on the West side, and I wonder why my bedroom is so cold. Thank you Mr. Money Mustache! I just got a little bit smarter.

    Reply

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