One of North America’s premier building scientists talks very practically and understandably about building enclosures.
We love Joe Lstiburek! One of North America’s premier building scientists talks very practically and understandably about building enclosures.
One of the biggest energy guzzlers in your home (besides, most likely, your thermal envelope, which lets expensive conditioned air escape through air leaks and poorly insulated walls) is the refrigerator. Upgrading it, believe it or not, can save you a bundle of money in the long run, as long as you don’t simply put your old fridge down in the basement and plug it back in. Now, before you balk at the high upfront cost of replacing your fridge, let us explain why we (admittedly, energy-efficiency/penny-pinching geeks) think it’s a good idea:
If you have an older fridge, it’s getting cool on the inside by running a motor that makes the room itself warmer, just like a heater would. If you have air conditioning, it has to work that much harder (also using electricity) to remove the heat from your house — so there’s a double-whammy penalty for having an inefficient fridge.
A friend of ours at Energy Circle (Tom) did a little research on a fridge he bought in 1998 (not too long ago), and discovered that replacing it with an Energy Star model (of the same design, size, etc.) that he could buy today would use less than 1/2 the electricity. If he got a more efficient design (i.e. freezer on top instead of side-by-side), it would use 1/4 as much. If he got the most efficient model of the most efficient design, it would use about 1/6th as much electricity. And none of this accounts for the important point that all of that inefficiency is released in the form of heat, which makes his house hotter! Yikes!
Energy Star has a great tool for calculating the savings of upgrading your refrigerator on their website. A quick test of the tool shows, for example, that replacing a side-by-side model from 1992 with a new Energy Star model would save about $125 per year (along with the savings garnered from having to run the AC less frequently).
We think the old refrigerator problem is actually bigger than most people think. The Energy Information Administration estimated that in 2001, more energy was used for refrigeration than for space heating, water heating, or lighting. We also have a great deal of faith in the Energy Star program itself: despite some recent criticism, the Energy Star label has been hugely successful in driving energy efficiency in appliances and electronics since the program’s creation in 1992; and, as we saw recently when the label was peeled from a number of LG and Kenmore refrigerators, the program continues to evolve and improve.
On a final note, it’s important to keep in mind that simply buying a new refrigerator, and sticking the old one down in the basement to keep a six-pack cold, doesn’t fix anything. To help drive the point, in addition to rebates and other incentives for purchasing Energy Star appliances, a lot of states are now issuing rebates for recycling your old fridge (essentially a cash-for-appliances program aimed at getting those old fridges out of the basement).
So the mantra is simple: refrigerate, recycle, rebate.
On cold winter days, a ray of sun streaming into your house can be most welcome – a free source of heat. But what about in the summer, when those rays of sun and other, less-evident solar heat seep into our already too-hot houses and become a costly nuisance? Well, what happens is that you lose money. But using landscaping (namely by planting trees) to shade your home can be a great way to lower energy costs.
Thanks to (get ready for a big word!) evapotranspiration (big, but not scary: it’s just the tree or plant releasing water vapor), air temperatures can be reduced up to 9° Fahrenheit in areas around trees, which creates a cool microclimate. Adeptly placed trees can cut air conditioning costs in the summer by 15%-50%, and one well-positioned tree has the daily cooling effects of five air conditioners running for 20 hours a day. And it’s easy to figure out where to place these trees: close to windows!
Shading east- and west-facing windows with trees can reduce costs in any climate, and south-facing windows just need a little more thought. In a hot climate? Go for it; shading will keep energy costs down year round. In a cold or mixed climate? Consider planting deciduous trees so you don’t run the risk of impeding welcome solar heat in the winter.
According to the Department of Energy, the average return on investment for landscaping as a means of low-energy cooling is less than 8 years. And if you plant trees as saplings, it’s likely that they will begin shading your windows within a year, and reach the roof within the next 5 to 10 years (depending on tree species and climate).
But then again, since when did we need to do an ROI calculation for planting a tree?
It speaks to the marketing savvy of window manufacturers and installers that, when faced with drafty rooms or high energy bills, most homeowners typically think that the best solution would be new replacement windows. While energy efficient replacement windows will likely lead to improved comfort and lower utility bills, the truth is that there are many far more cost effective solutions to improve your home’s comfort and energy efficiency.
Whatever tax breaks or special deals may be going on in your area, the fact remains that replacing your windows is a labor-intensive, high-material-cost job that will likely set you back in the tens of thousands. If you’re to invest in one of the varieties of very energy efficient windows on the market, the price will be even higher. Even if you were to reap significant energy savings from your new windows, the payback period from an energy standpoint will be several years at the earliest.
Due to a phenomenon called the Stack Effect, whereby cold air enters the home through holes in the basement or crawlspace and rises as it heats up, through the living space and into the attic, the majority of the heat loss in your home typically takes place through holes in the basement and the attic. While leaky windows are certainly responsible for some heat loss, and some drafts, focusing on the more significant leaks in the attic and basement is a far more cost-effective way to reduce your energy bills and improve your home’s comfort.
Focusing on these big air leaks in the basement and attic is typically far less expensive than replacing all of your home’s windows. Consider hiring a qualified home energy auditor to determine where the most significant air leakage is taking place, or hiring a full service Home Performance contractor to use energy auditing diagnostic tools like blower door testing and infrared imaging to pinpoint the air leaks and seal them up in one fell swoop.
Once your home’s air leakage is reduced, consider beefing up your home’s building envelope with increased insulation. Products like spray foam and blown-in cellulose insulation are typically better at stopping air movement than traditional fiberglass batts, so consider these options when hiring an insulation contractor to increase the R-value of your attic and walls.
For more information about how to save energy and improve your home’s comfort cost effectively, feel free to contact us directly. We’d be happy to help with any questions you may have.
Winter’s coming. It’s already heating season. So how do you save money on heating costs? You’ve got to own your heat. Simple as that. You’ve paid for all that warm air already, so it doesn’t make much sense to waste it now.
A simple enough premise – it’s the application that gets complicated. We (and most building science experts) strongly recommend air sealing and insulation as high priority measures to make your home use less energy, make you more comfortable, and make the planet happy.
Air sealing can sometimes be done by a competent do-it-yourself-er, but insulation is trickier. It generally has to be done by a contractor, and for the most part can only be installed by getting inside walls that are now closed up. And unlike air sealing flaws, which you can often see just by scanning your basement walls, the quality of insulation in your house is, for the most part, difficult to assess. (Thankfully, the attic, which is the most critical spot for insulation, is the easiest to access).
This is an important point, because even if all insulation is created equal (a separate discussion), that doesn’t necessarily mean that all insulation is equally well installed – which, in this case, may be just as important. Insulation only works when it’s installed to specifications, and when it’s in good shape. So even if there is insulation in your walls, even if you’ve seen it or paid for it or been told by your real estate agent that it’s there, it may be sleeping on the job.
The best way to assess the quality of otherwise “invisible” insulation is a home energy audit from a qualified home energy auditor with an infrared scanner, which will reveal where there are problems with your insulation.
Another reason why a home energy audit is really a problem-solving exercise. After you have it done, you’ll know where the issues are. Without it, your home might just remain an unsolved mystery… The Case of the Cold House and the Disappearing Dollars.
You may have heard about home energy audits before, but maybe you’re not quite sure that you need one. After all, your home is relatively new. It’s pretty comfortable most of the time, and your utility bills aren’t that bad. Maybe you’ve switched out your incandescent light bulbs for CFLs, and upgraded to a low flow showerhead, so figure there’s not much more you can do.
Well, there’s a lot more to home energy than lightbulbs and solar panels, and a home energy audit is the place to begin. Here are 5 ways that a home energy audit from a certified home energy auditor will likely improve your life — right away.
Energy savings are one of the primary reasons people sign up for energy audits, but oftentimes they’re actually more excited about the improved comfort once the work is done. Cost savings are good, but there’s something hugely refreshing about walking into a once-cold room for the first time after an energy retrofit and noticing that the drafts are all gone.
The amount of money you can save on heating and cooling bills varies from home to home, but it’s typically substantial. Most new homes built to code are grossly inefficient. Insulation is often improperly installed; air leaks around service penetrations, windows and doors are abundant; and leaks in the building envelope often permit uncontrolled moisture to enter the home – causing indoor air quality problems and potential durability risks.
According to the EPA, indoor air quality is a greater threat to public health than outdoor air — even in the most polluted cities. This is because of chemicals from building materials, mold and other toxins caused by uncontrolled moisture, radon, dust, and a variety of other factors; and is compounded by a lack of adequate, controlled ventilation. An comprehensive energy audit takes each of these factors into consideration to ensure that your home is not only energy efficient, but safe.
A home energy audit is the first step toward a more energy efficient home. In an era of turbulent, rising energy prices, homebuyers and real estate professionals are increasingly looking at a home’s operating cost as a point of value when looking at homes. An energy efficient home has lower energy bills than an inefficient, code-built home, making it an attractive option.
Do you know how much energy your home is wasting? Are you sure that the air in your home is safe to breathe? Is there radon in your basement? Are air leaks in your ceiling causing moisture to build up and pose a risk of rot and structural damage? During a comprehensive energy audit, you’ll get an answer. Considering that your home is likely the biggest investment you’ll make in your life, it’s worth ensuring that it’s safe and healthy. We can help.
Contact us for more information, or to schedule an energy audit today.
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