Sustainability Now

Summer Heats Up!

How can you cut down on your a/c bill and still keep a comfortable home? Let me count the ways, and there are many:

  • On cool nights, open the windows and just run the fan to help circulate air around the house. So often, I hear people’s air conditioners running when it is a cool 60 degrees outside. I am sure their house is hot, but we can let Mother Nature do some of the work and save. Purchase a couple of fans and place them near windows to take the cool air in. You can even get really fancy and get a whole house fan installed, but that does take some skilled carpentry, and I don’t recommend the cheap kinds from the big-box stores. They don’t seal tightly when not in use, and so will just drive up your heating costs in winter.
  • Don’t run you’re a/c with internal doors closed (bedroom, bathroom). Ever blow up a beach ball? What happens when it is filled with air? You keep blowing, but does it get any bigger? You can’t get any more air into that ball. Same thing happens to your room with an a/c vent and a closed door. Once the room “pressurizes” with the air going, no more cool air is going to get into that room. You are just running the fan for nothing, other than lining the utilities pockets.
  • Consider raising the set point a degree or two. Okay, so you won’t quite live in an icebox, but you might save some energy and cash at the same time.
  • Do you have a programmable thermostat? If so, have you figured out how to program it yet? Do some light reading and give it a try so that when you leave the house regularly, it will turn off automatically. It is a pretty cool feature, actually. If you want to get really fancy, you can even get one that links to your smart phone, but you’ll need to hire an a/c guy to wire that up.
  • I bet a good portion of the air you are cooling is not even making it to your room. On average, 28% of the air you are paying to cool ends up in your walls and attic, not in your rooms. That is like saying 28 cents of every dollar you are tucking away into your attic, but not in the good way. Take a grill off the wall or ceiling: is there a gap or space between the metal box and drywall? If so, get some caulking (any kind will do) and fill it. Why send cool air right into your wall cavity? Want to keep the mice comfortable? If you really want to know how much your ducts leak, you can even hire a guy called a HERS (Home Energy Rating System) rater and he or she will tell you exactly how much you are wasting.
  • When was the last time you changed the air filter? Just like you car’s air filter, you have to change your a/c’s filter regularly; otherwise you are stressing its “engine” and likely will break it. And skip the really expensive “MERV 13” one. Your air condition is not a whole house air cleaner and was never designed to be one. That is like putting a HEPA filter on your car’s air intake. That can not possibly improve efficiency, and really does little for indoor air quality.
  • Want to be really brave? Go in your attic and double check that all the ducts are connected. It is not such a rare occurrence to find a broken duct up there.

So, take a moment or two, and give that great big machine a little TLC; the environment and your pocketbook will thank you.

Dav Camras is the owner of HouseSmart Green Solutions (, has extensive experience in the technical aspects of green science with an MS in water and wastewater treatment, certifications as a HERS Whole House Rater, Certified Green Building Professional and BPI- Building Analyst. To promote greener living, Dav started HSGS, a home energy consulting firm.