Every year as the weather starts getting warmer, the SO and I have the same debate: should we get air conditioning installed or not? We'd have to go with the ductless kind, as our house comes equipped with radiators, but that's not where the quandary lies. During the few hot and humid weeks of the year (not that they feel like few when you're suffering through them), there is nothing quite as wonderful as walking into a refrigerated building. But much as I don't like the heat, I'm also not a fan of the artificial cold. Even in the car (where I think AC is an absolute necessity), I have to set it to where it's only a step above warm, otherwise it's uncomfortable. But aside from personal preferences, air conditioning is a huge drain on power. It's so bad that our local power company is desperate to get people to sign up for a program where the company can remotely cut your AC when power demands are at their highest (this is to help prevent rolling blackouts). At a time when the world really needs to think about conservation and smart use, do we really want to install an energy hog?
Luckily, there are ways to keep the house cool and comfortable (but not cold) without resorting to AC. Some of these we already have in place, some we're planning on trying out. Most of these came from Home Comforts (whose author claims her grandmother's house was always pleasantly cool in summer), and a couple are my own. If you have any tips of your own on keeping cool, please comment and share.
Keeping Cool without AC
*If you can, install exterior shutters, shades or awnings on your house to help block out the sun. Light colours reflect more heat.
*Interior shades, blinds or draperies also help a lot. Anything that can block the sun will help (so if going for draperies, make sure you get an opaque, tightly woven fabric). Again, light colours reflect more heat. In fact, two layers (blinds/shades and draperies, or two sets of draperies) are best of all. They'll help keep the house warmer in winter too, by blocking out drafts.
*Ventilation can help if the outside temperature is lower than the inside temperature. A good idea is to open windows to let cool air in at night and in early morning, and to close blinds and draw curtains during the sunniest, hottest part of the day.
*Use appliances selectively. Don't use the oven on hot days (for some reason I always get the urge to bake on the hottest days of the summer. No idea why). Limit use of the stove, dishwasher, and clothes dryer (or use them at night), and close the doors of the rooms they're in when using them. Speaking of, TVs and computers can emit a surprising amount of heat; don't turn them on unless you really need them (another reason why summer is a great time to catch up on your reading).
*Fluorescent lights produce far less heat than incandescent bulbs (in fact, some people have complained that after switching to fluorescents, they had to turn up the thermostat in winter because the lights were no longer providing extra heat).
*I cannot emphasize enough the awesomeness of fans. I have tabletop and floor fans in every room (ceiling fans are also really good, but I find them unattractive). Not only will fans cool you and the house down using far less energy than AC, but they'll circulate the air and make your home generally more pleasant to live in. Even with AC, I'd keep the fans for this latter reason.
*Dehumidifiers are great as too much humidity makes you feel hotter (not to mention icky). Dehumidifiers emit some heat, though, so we keep ours in the basement and turn it on at night. You'd be amazed how much water you collect.
*Plant shade trees (e.g., elm, maple, oak, sycamore, ash)! They can lower temperatures around them by up to 9F. Deciduous trees are best, as they drop their leaves in winter and allow the sun back in to warm the place. Bushes and vines on trellises near the house also help. Trees should be planted on the northeast-southeast and northwest-southwest sides of your house. Don't plant too close to your house or you'll block breezes (and don't plant trees where their roots will get into water pipes).
*Insulating your attic makes a huge difference, as apparently that's where most of the heat enters your house (an insulated attic also helps keep heat in during winter). Interestingly, venting your attic is also an excellent cooling measure. You should probably hire a pro for this, but if you're feeling handy make sure to place intake vents low and exhaust vents high. You might also want to make sure you install some kind of secure screening to prevent critters from getting in.
*A light coloured exterior will help reflect heat away from your home, but if you're lucky enough to have an old house with original red/brown bricks, I strongly urge you not to paint or cover them. Those old bricks are gorgeous, and have a patina that can't be replicated. Painting them just looks bad.
*You can buy reflective roof coatings to help lessen heat absorption. Home Comforts doesn't mention them, but I have to wonder about different types of roofing materials, as well. You might want to look into whether terracotta, ceramic, or aluminum shingles and tiles would help keep the house cooler, and also whether they're practical for you.
*Make sure your bathrooms are vented. They help suck out humidity and maybe some heat as well. Anyone who's ever showered in the summer in an unvented bathroom (right here) can attest to the sauna-like effects once you step out of the enclosure.
If the heat still gets to be too much (as it might, especially during a bad summer), I suggest cooling off with ice cream, cold watermelon, quick showers (or running under the sprinkler), and occasionally escaping to a beach, pool or public building (libraries, malls, community centres...) You should also keep a close eye on pets! Make sure they have plenty of cold water available and a shaded area to sleep (preferably inside). Dogs overheat more easily than cats, so watch them extra closely. And do not, ever, under any circumstances, no matter what, leave them in your car! Not even for a second while you run inside. (Same goes for kids, although I hate that it even needs to be said in either case.) Cars are ovens on sunny days.
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