The summer is ongoing and many places are in the middle of a heat wave. The tips below will help you keep your home cooler with or without air conditioning.
Tip 1. Drink – a lot
On a normal day drink six to eight glasses of water. On warmer days or if you exercise, drink more. According to British Telecom’s Home website, “If you’re feeling light-headed, tired or you have a headache today, you probably haven’t drunk enough.” They mention that at 1% fluid loss humans are thirsty. At 2% one is officially dehydrated, so it can happen a lot faster than we think!
Tip 2. Makeshift AC
You’ve probably heard about the trick of putting a bowl of ice in front of a fan. Well, the New York State Office for the Aging suggests using bottles of water instead
. “Fill three plastic soda bottles full of water, freeze them but in a manner to not damage them (liquid expands on freezing), then place them in a large bowl,” the agency’s website states. “Position a fan to blow on them… The water in the bottles can be refrozen and used repeatedly.”
Tip 3. Creative use of your fridge
Seattle City Light
suggests putting lotion and moisturizers in your fridge to cool down your skin.
Tip 4. Unplug
Unplug electronic devices that you’re not using. Even if they’re not powered on, they may still be using electricity and giving off heat. This includes devices which may be "off," but are really in "instant-on" mode. Unplug them or turn off the power strip to which they attach to save even more heat (and money, both to run for no use and cooling to remove the heat!).
Tip 5. Window treatments work
The US Department of Energy
recommends closing the shades and curtains on your windows on summer days — especially the ones that receive direct sunlight. “Studies demonstrate that medium-colored draperies with white-plastic backings can reduce heat gains by 33 percent,” the DOE website states. Another pro tip: hang curtains as close to the window as possible.
Tip 6. Set the dial higher
This Old House
says if your air conditioning has a programmable temperature sensor set it for 78 to keep cool. You'll save 5 to 8 percent on cooling costs with each degree above that mark. For a typical household, setting the thermostat at 80 degrees saves 10 to 15 percent; raising it to 85 degrees will save 35 to 55 percent.
When you leave home for more than one hour, set the thermostat to 85 or 90 degrees. Reset it upon your return, and the room will cool down in only 15 minutes. The system will use less energy during the cool-down period than if you had left it running at a lower setting while you were out.
Typical air-conditioning settings for a programmable thermostat at different times of day:
6 a.m. to 9 a.m. = 75 degrees
9 a.m. to 5:30 p.m. = 85-90 degrees
5:30 p.m. to 11 p.m. = 75 degrees
11 p.m. to 6 a.m. = 80 degrees
Benefit: 15 to 20 percent or more off your cooling bill
Tip 7. Avoid setting air conditioning too low
Put a thermometer in front of your running air conditioning unit for a few minutes to see how cold it gets the air. Set your temperature two degrees higher than that, at minimum, so the unit will cycle as it was designed. Setting the temperature less than that guarantees it will never cool your house to that temperature – leaving it to run constantly, chewing up your energy bill.
Tip 8. Install a programmable thermostat
Also from This Old House
, a programmable thermostat lets you preset temperatures for different times of the day, so air-conditioning is working only when you are home. The least expensive thermostat models ($30) let you set four cycles that, unless manually overridden, repeat every day. Higher-priced models ($50 and up) allow you to create settings for each weekday and for each weekend day.
Benefit: Up to 20 percent off your cooling bill
Tip 9. Maintain your air conditioner
To keep your AC unit running in tip top shape, the Department of Energy recommends replacing the filters every one to two months
— a clean filter can lower the air conditioner’s energy consumption by 5 -15 percent. And remember to check the air conditioner fins. “Are the fins on your evaporator or condenser coils bent? If so, they may be blocking airflow,” the DOE website states. “Look for a “fin comb” at an air conditioning wholesaler to get them bent back into shape.”
Tip 10. Use a Fan
Once again from This Old House
, a fan, which costs two to five cents per hour to operate, will make a room feel 4 to 6 degrees cooler. Also, a fan works well in tandem with an air conditioner because the dehumidifying action of the air conditioner provides drier air that the fan can then move around.
In frequently used rooms, install a ceiling fan (set it to spin counterclockwise in summer). You'll save the most money by running the fan only when you're in the room. A motion-detector switch (around $20), which turns the fan on when you enter a room and off when the room is empty, is a good addition. However, if you have pets that move in and out of the room, make sure the switch can be turned off manually. Otherwise, your pets can cause the fan to run while you're away.
If nighttime temperatures drop into the 70s where you live, you might want to purchase a whole-house fan, which runs $300 to $600 installed. This type of unit goes in an upstairs ceiling, ideally in a central hall. When run at night with the windows open, the fan will pull cool air into the house as it vents hot air out through the attic. Most models are designed to slip in between joists for easy installation. Whole-house fans, which draw only as much power as a couple of lightbulbs, are usually outfitted with a variable-speed switch and/or timer. If you install one, be sure to get an insulated box to cover the portal in winter.
Benefit: Ceiling fans can decrease your cooling bill by up to 15 percent, while a whole-house fan can slash it by 50 percent.
The Department of Energy
says that window fans are best used in windows facing away from the prevailing wind and exhausting hot air from your home. “To cool as much of your home as possible, tightly close windows near the fan and open windows in rooms far from the fan,” the DOE website states. “In multi-level houses, the fan should be located on the upper level, if possible, and the open windows should be located on a lower level.”
Tip 11. Practice "Texas Cool"
"Texas cool" is a morning and evening routine that takes advantage of cool outdoor temperatures at night and keeps the heat at bay as much as possible during daylight hours. It's very simple to do: at night when the temperature drops, open windows and bring in cool air with window fans or a whole-house fan. As soon as the sun comes up or the air starts to heat up, shut the windows and shades and keep doors closed.
Benefit: 20 to 50 percent off your cooling bill
Tip 12. Use sun blockers
As much as 20 percent of summer heat enters your home as sunlight shining through windows. To cut "solar gain," add curtains or blinds to rooms that get direct sun and draw them in daylight hours. With the shades drawn, a well-insulated house will gain only 1 degree per hour when outdoor temperatures are above 85 degrees.
Pay special attention to west-facing rooms late in the day. Shades and blinds to consider include roller shades (the least expensive option), venetian-type micro-blinds, reflective curtains and insulated curtains (the most expensive, at $100 per window). Two exterior options are to install awnings or plant shade trees.
Benefit: Up to 20% of your cooling bill
Tip 13. Install awnings
Window awnings can reduce the solar heat that enters your home by up to 65 percent on south-facing windows and 77 percent on west-facing windows, according to the DOE website.
Tip 14. Cook smart
Any appliance that generates heat adds to your cooling load. An oven baking cookies can easily raise the room temperature 10 degrees, which in turn jacks up overall cooling costs 2 to 5 percent. Save cooking (especially baking) for cooler hours or cook outdoors on your grill. It is also a good idea to run the dishwasher and clothes dryer at night.
Benefit: 2 to 5 percent off your cooling costs
Tip 15. Get cooler lights
Incandescent bulbs don't contribute as much heat as unshaded windows, but they do add heat to a house and can raise the perceived temperature, sending you to the thermostat to seek relief. To reduce this hot-light effect and save lighting costs year-round, replace incandescent bulbs with LED bulbs. They use about 80 percent less energy and emit 83 percent less heat.
Benefit: Up to 5 percent off your cooling bill plus electricity savings
Tip 16. Snug up the ducts
Leaky ducts can cut into air-conditioning efficiency. Ductwork must be balanced between the supply and return sides of the system for it to work safely and efficiently, so making a repair in one section can cause a problem in another. Leak-prone areas include the return plenum; where branch ducts meet the trunk line; and where ducts attach to outlets. Also, insulate ducts that run through a hot attic with a blanket of R-11 fiberglass insulation.
Unless the duct repairs are minor, it's wise to leave them to a HVAC pro. While the contractor is on site checking your ducts, have him tune up the air-conditioning unit by cleaning filters, unplugging coils, unblocking drains and lubing the fan.
Benefit: Up to 40 percent off your cooling bill
Tip 17. Seal air leaks
The places where cold air infiltrates in winter are routes for hot air in summer. And what's worse, hot air is often accompanied by high humidity, making you even more uncomfortable. Armed with a flashlight, exterior-rated silicone caulk and a couple cans of expanding foam insulation, hunt down and seal all leaks. Concentrate on the attic, basement and crawl space; pay close attention to anything that passes through a ceiling or wall, such as ductwork, electrical or plumbing conduits and kitchen and bath vents. Other common leaky spots are around windows and doors. If you can rattle a window, it's leaking. Seal it with weather stripping.
Benefit: Up to 10 percent off your cooling bill
Tip 18. Defeat attic heat
The temperature in your attic can reach 150 degrees on a hot summer day, a situation that if left unchecked can drive up cooling costs by as much as 40 percent. If your attic has less than R-22 insulation—7 inches of fiberglass or rock wool, or 6 inches of cellulose—you should add more. (The U.S. Department of Energy says most homes should have between R-22 and R-49 insulation in the attic. To check what's right for your region, go to the Department of Energy website.)
Before insulating, seal around recessed lights, vents, and plumbing and lay down a 6-mil polyethylene vapor barrier. When insulating, place boards across the tops of the joists to walk on, and as you insulate, don't cover or pack insulation around a bare stove pipe, electrical fixtures, or any other equipment that produces heat, unless the fixture is labeled as suitable for direct contact with insulation. Otherwise you risk fire.
Also make sure your attic is ventilated. Gable vents (around $25 each, plus $75 per vent for labor) can lower attic temperatures about 10 degrees; a ridge-and-soffit ventilation system (an extra $200 during re-roofing) will reduce attic temperature to around 100 degrees.
When re-roofing, use white or pale-gray shingles instead of dark ones. These keep the attic cooler than dark shingles.
Benefit: Longer shingle life, and up to 20 percent off your cooling bill.