If the latest report from the Intergovernmental Panel on Climate Change was a jolting wake-up call, you may be wondering what else you can do to slow climate change. You’ve voted for people you knew would care about climate change, divested from companies that are making the situation worse, and replaced all your incandescent light bulbs with LEDs a couple of years back.
Today is a great day to get started on a plan to reduce how much energy your home uses and make that energy cleaner. Making a plan will help you decide where to start. If a particular project sounds fun and easy, do it soon. If something feels too expensive or like maybe too much work right now, plan how it would be possible to tackle it by saving up, hiring someone to do the work, or working with friends.
The three biggest energy drains for most houses are heating, air conditioning, and hot water, according to William Healy, PhD, of the National Institute of Standards and Technology.
“The first thing to do,” he says, “is to build really airtight walls and really insulated walls. Once you do that, put in really efficient equipment, such as water heaters and lights.” Healy, an engineer who is an expert in energy efficient housing, manages the Net-Zero Energy Residential Test Facility at NIST.
NIST’s test facility has shown that a house can generate as much energy as it consumes on an annual basis, in short, “net zero.” Healy says solar panels should typically come last; but solar panels put a home within reach of net zero, as well as superior comfort and vastly reduced utility bills.
Do an energy audit of your home
Begin by doing an energy audit, to find out where your home is losing energy. You can hire someone to do the job, but there’s a lot you can figure out yourself. Check out these tips from the US Department of Energy on how to do your own energy audit. We also have our own guide here. Consider investing in a thermal camera that attaches to a smartphone—the infrared camera can tell you where your home is losing the most heat. Snap photos from the outside of the building or walk around inside on a cold night. (The photos will be useful later when you are prioritizing work.) If you are into gadgets, this one is fun and will pay for itself.
Define your house’s “envelope”
One of the first things to think about is your home’s building envelope. That’s basically the line between indoors and outdoors.
Is your attic inside or outside the living space that you heat and cool? How about a basement or crawlspace? Your goal is to define the building envelope, seal it off from the outside world, so air is not leaking in and out of the space you live in, then insulate that sealed envelope. We’ll start at the top. But here are some likely places for major air drafts.
Seal the attic
One of the cheapest and easiest things to do is to seal off air leaks where you are losing heated and cooled air. It’s painstaking work but it makes a huge difference.
Air sealing, says Healy, is the best single thing you can do to increase the energy efficiency of your home. “The data is very clear. That’s the biggest bang for your buck… Because that’s generally where we are losing most of our energy.”
An attic is usually outside the building envelope and vented to the outside. Holes in the ceiling, made for light fixtures or bathroom fans or just the top of a wall, allow cold air from outside to flow into your home. Cold breezes from a light fixture, for example, can create uncomfortable drafts. It’s like leaving a window open.
Cold air even falls down inside walls, where it sits absorbing heat from your bedroom, even flowing out into a room through light switches, electrical outlets or where plumbing pipes come through the wall, in the bathroom or kitchen. If you put your face next to a light switch you might feel a tiny breeze. Brrr!
You can go around trying to seal every light switch and plumbing hole, and you probably should. But first, stop air flow at the source. Climb up into the attic and methodically seal every gap, from the very edges of the attic, over the exterior walls, to the holes drilled for electrical wiring or plumbing pipes. Or hire someone to do it. Here’s how it’s done.
If you can’t afford to hire help and don’t want to do an attic by yourself, consider collaborating with a small group of friends, forming a work party to air seal 3 or 4 attics over several weekends. Then celebrate together and plan what to do next.
Insulate your attic
Insulating your attic delivers the best return on investment of any remodeling project, reports the Rocky Mountain Institute, in terms of finances, joy, comfort, and health.
You can use fiberglass bats (and even lay them in yourself), but bats can leave gaps here and there. Alternatively, you can pay someone to blow in insulation that covers everything. It’s like having a down blanket over your house.
Once the attic is sealed and insulated, the home will be warmer, less drafty, and quieter. Pat yourself on the back and enjoy your cozier home!
Find all the gaps
Seal any remaining gaps in your building envelope from the inside, around light switches, electrical outlets, light fixtures and plumbing pipes. This is pretty easy. Next tackle weatherstripping doors and windows, which scores of YouTube videos offer to explain. (If you want to go all nerdy on the best weatherstripping, check out Conservation Technology.)
Nobody will blame you if you put this off, but, eventually, seal the building envelope’s floors, plus the rim joists, which hold up the house. Depending on the house, this can be a big project, and contractors have myriad ways of approaching the problem, including spray foam, solid insulation boards plus beads of foam sealant, or masking off the whole underside of the house with thick plastic sheeting.
Upgrade to electric appliances
An essential component of reducing carbon emissions is to use electricity instead of fossil fuels. In principle, electricity can be generated from zero emissions sources like solar and wind, and electricity is getting cleaner all the time. If your appliances are electric, you will eventually be able to run them without fossil fuels. But if they run on gas, you will always be burning fuel. In the long run, that’s more expensive for you and for the planet.
If your gas water heater needs replacing, choose an electric heat pump water heater. Replace a furnace with a system of ductless mini splits. These super efficient appliances run off electricity, can both heat and cool your house, and won’t blow dusty air around the house. A gas cooking stove can be replaced with an electric one. Induction cooktops have the same instant-on/instant-off behavior as the gas flame that cooks prefer.
And for refrigerators, dishwashers, and washing machines, choose models that are the most energy efficient, as rated by Energy Star. Plug electronics into power bars that can be shut off when not in use. And, yes, replace old light bulbs with LEDs.
Prioritize if you can’t do everything
If you’ve gotten this far, you’ll realize there’s a lot to think about and a lot of pieces to consider. Every house is different and everyone has different finances and considerations. So, before you begin, think about why you want to make your home more energy efficient. Is it to save money and feel more comfortable? Or is it to get to net zero?
For example, a new gas furnace might be cheaper than electric ductless minisplits, depending on your house. In the long run, you’ll save more money and generate less greenhouse gas with the minisplits, but in the short term you save money with the gas furnace. Or maybe a contractor offers to insulate the underside of your house, but your thermal camera tells you are losing far more heat through your windows. If you can’t afford new windows, maybe you can put up thick curtains for not too much money. Curtains are great if that’s the right choice for you.
The main thing is to prioritize what will get you closest to an all-electric future in which you reduce your overall consumption of energy. Amazingly often, that saves you money in the long run and reduces your carbon footprint too.