This time of year all many of us can think about is keeping cool. But escaping the searing heat that blankets entire swathes of the country comes at a cost. In my 130 year old Victorian, summer utility bills are stratospheric. But where does a person turn for help making decisions about cooling off when it seems like everyone has something to sell? Roofs, windows, air conditioning systems, insulation — companies making and selling these products all have their claims about cooling and energy savings. And how do you separate fact from myth when it comes to adages about keeping a home cool and keeping a lid on the utility bill?
Fortunately a couple of experts weighed in for NBC BETTER with some tips for how you can keep cool and carry on this summer. Lauren Urbanek is a senior program advocate, Center for Energy Efficiency Standards, Climate & Clean Energy Program at the Natural Resources Defense Council. And Robert Daguillard is a spokesperson for the U.S. Environmental Protection Agency. They helped us break down some cooling essentials.
START WITH YOUR WINDOWS
It sounds basic, Urbanek said, but “if sun comes in through your windows it’s going to make your house warm. Using things like window coverings to their full advantage in the middle of the day [can] keep your house cooler by keeping that sunlight from coming in, particularly if you are gone during day, and in rooms that face west or south.”
Anybody else’s grandma do that back before air conditioning was ubiquitous? She knew what was what.
So what’s best for window covering? Looking for a product like a thermal curtain that’s designed for that purpose is generally a pretty safe bet, Urbanek said. “The idea is to keep the light and heat from coming through.” That could even mean having a thicker curtain vs. something sheer. Of course there are also thermal shades (we use those on south and west facing windows and they make a dramatic difference), actual blackout curtains, even interior shutters.
Yeah, you might be giving up light and a view, but isn’t it nice to be cool?
HOT AIR IS LIKELY COMING IN FROM EVERYWHERE
If you were to add up all the little cracks and places in your house where warm air gets in, the average house would have a hole the size of a basketball, Urbanek said. “If you had a basketball sized hole in your wall you’d take care of it right away.” What people often don’t know, she said, is how many places you can have hot air coming in: think around windows, door frames, and crawl spaces, even around recessed lights.
“If you were to add up all the little cracks and places in your house where warm air gets in, the average house would have a hole the size of a basketball.”
A great resource for finding all those little culprits, she said, is your local utility company. Many can provide a home energy audit and some even offer rebates if you take their advice. “You get a professional to do some diagnostic testing and they will give you a list, generally with information about what makes the most sense to invest in,” she said. (Don’t wait; I called mine weeks ago and the soonest they could come is mid-August.)
INSULATION IS KEY YEAR-ROUND
All those beautiful photos you can find on Pinterest of glorious exposed rafters notwithstanding, insulation is a must, Urbankek said. She lives in a century-old house herself, and although “it’s not something fun to spend money on — even as somebody who knew this was the right thing,” adding insulation to the walls and attic was one of her first priorities. “It’s not as fun as new countertop but it will save you money and make you more comfortable in your house.”
How exactly does insulation work? “The way thermodynamics work is heat flows from a hotter place to a cooler place,” Urbanek explained. “Not having insulation means heat is seeping into your house and your air conditioner is having to work a lot harder.”
Or, to use the words of the insulation contractor who came to our house to take thermal images, “heat is screaming in through your ceiling.”
WHEN AND HOW TO RUN YOUR AIR CONDITIONER
It’s an age old debate: is it better to leave your air running all day so the house stays cool and it doesn’t have to work so hard to get back down to a comfy temperature? Or should you set your thermostat a few degrees higher when you’re not home?
It’s all about equilibrium, Urbanek said. “Heat is going to flow from a hotter environment to a cooler one. So in this case the heat will want to come from outside into your nice cool house. If you set your thermostat higher so it’s warmer in day there’s going to be less air flow. If it’s 85 out and you set it to 65, the air conditioner has to work harder. Now if you set it to 78 during the day and set it back [lower] when you get home it may have to work a little harder and run longer … but at the same time it’s not going to be running all day.”
This also speaks to importance of a programmable thermostat, she said. “That allows you to set your temperatures and forget about it.” This is another area to check with your utility company to see if they have thermostat rebates, she said. Of course what’s really nice is a wifi thermostat you can control with your phone so you can cool your house before you get back home.
The same rule of thumb applies with window unit air conditioners, Urbanek said. Turn them off or to a higher temperature while you’re gone. I’ve learned that the hard way when letting a cooling system run too hard for too long (a new mini split in my third floor in a typical Kentucky summer) fried the fan motor. (Yes, I’m getting new insulation.)
HOW TO SHOP FOR AN A/C UNIT
What if you have a window unit that can’t keep up? “You may not have a correctly-sized unit for your room,” said Daguillard. Tempted to go big? “An oversized air conditioner is actually less effective — and wastes energy at the same time. Air conditioners remove both heat and humidity from the air. If the unit is too large, it will cool the room quickly, but only remove some of the humidity. This leaves the room with a damp, clammy feeling.”
And of course look for an ENERGY STAR certified air conditioner. They use 10% less energy, and on average, cost $70 per year to run, Daguillard said. Then be sure the unit is installed correctly. “An improperly installed room air conditioner leaks as much air as a 6 square inch hole, increasing energy costs and making your home less comfortable,” he said.
A BETTER WAY TO BEAT THE HEAT
One of the simplest solutions of all, Urbanek said, is to focus more on what the air feels like than the actual temperature. “If you have ceiling fans make sure you’re using them — and the right way, making sure the direction is set correctly. As you’re standing under it looking up, it should be running counterclockwise … it pulls cooler air from ground and blows it back on you.” Just the air from the fan “on your skin can make a room feel ten degrees cooler,” she said. And no need to run it if the room is empty, she added. “It does nothing but use energy.”