by Shana Fong on August 18, 2010
Here’s a piece written by Matt Golden and Jess Chamberlain for Sunset Magazine on best practices for keeping your house cool, the environmentally friendly way.
To keep a house cool, it’s really about either:
- Keeping the sun out, or
- Keeping the air cool/conditioned
In a retrofit situation, you have to first assess what your possibilities are:
- Is there an attic we can insulate?
- Are there eaves that are blocking some of the summer sun?
- Is there an existing cooling system?
This really affects what the best approach to take is.
For an average house in a cooling climate with an attic, we’d recommend reducing the cooling load as much as possible and utilizing passive cooling:
1. Air sealing
2. Adequate attic insulation (min. R-38) to create a thermal barrier
3. Radiant barrier, if there are ducts in attic; on roof decking or in attic
4. Low-E glazing on windows
5. Whole-house fan
This route is very cost-effective from a long-term standpoint; i.e. you’re not paying to condition the air, you just pay for the equipment and installation.
The other option is to actively cool the house, in which case you’d invest in the fundamentals (such as air sealing and insulation), then install a high SEER-rated AC unit (min. 16-18 SEER rating) designed to ACCA’s manuals J, S, D & T. If air handling equipment is located in the attic we would recommend encapsulating the attic with air-impermeable spray foam and bringing the attic into the building envelope. This prevents hot attic air (150˚F+) from infiltrating the duct system.
Easy Cooling Tips:
- Keep your AC unit in the shade
- Keep the coils clean
- Install high efficiency lighting (it keeps house cooler)
- Turn plug loads off
- Stop the sun before it gets into your house – use external shading, overhangs, and deciduous trees
- Low-E coating on windows
by Shana Fong on July 19, 2010
The gaps you can find around the windows and doors of the average American house add up to the equivalent of a hole in the wall that measures 10 inches by 10 inches.
Your house has more leaks than the CIA. There are cracks all over the place. Your doors and windows don’t quite meet their frames; there are tiny spaces where the walls almost join the floor; there are open areas around your electrical and plumbing outlets. And these little gaps eat energy. In fact, an amazing amount of heat in the winter – or cool air in the summer – escapes through them. But you have two simple weapons to fight with: caulking and weatherstripping.
Energy Facts
- Caulking and weatherstripping an electrically heated home can keep some 1,000 pounds of CO2 out of the air. So if 1,000 of these homes were weatherized, over a million pounds of CO2 would be saved.
- Believe it or not, stopping air infiltration can reduce your home’s heating and cooling bills by up to 40%.
- People are concerned that although weatherstripping may save energy, it will keep fresh air out of their homes. While it’s true that some ventilation is necessary, it’s really not much of a problem – a typical house may get twice as much fresh air as it needs. In other words, the air is probably flying out of your house as quickly as you’re heating or cooling it.
Caulking vs. Weatherstripping
- Cracks without any moving parts – like the places where a wall in your house meets the outside edge of a window frame, or two other dissimilar materials come together – can be sealed with caulk.
- The places where doors and windows close into their frames can be sealed with weatherstripping – cleverly designed strips of felt, rubber, metal, or plastic that fill the spaces around doors and windows, and compress when you shut them.
- Weatherstripping materials come in many styles. Some are self-sticking, so you don’t even need a hammer to install them. Others must be nailed on. Still others are crafted so pieces on the frame and the door lock together when the door closes.
- One of the trickiest places to weatherstrip is where the door meets the threshold. Special “shoes” and “sweeps” are available to stop these air leaks.
- Besides saving energy, weatherstripping and caulking have an additional benefit: By stopping drafts, they’ll make your home more comfortable.
Leak Patrol
- Some evening, when your house is at least 20°F warmer than the outdoors, hold your hand up to various places around windows and door frames. If you feel any drafts, the windows and door frames need weatherstripping.
- You can also use a smoking incense stick to look for drafts. Hold the stick near places you think might have cracks; if the smoke dances or gets sucked in, you’ve found a place to seal.
- Many of the biggest air sealing opportunities are up in the attic and below your floors. For these harder-to-reach leaks, it’s a good idea to call in a trained professional such as Recurve to quickly identify and remedy your home’s major leakage areas.
Excerpted from 30 Simple Energy Things You Can Do To Save The Earth, by The EarthWorks Group.
by Shana Fong on July 16, 2010
Is your thermostat accurate? If not, chances are that the temperature sensor is being affected by cold air coming through the opening where the thermostat is mounted.
Keeping control of your thermostat is one of the simplest ways you can save a great deal of energy – and money – all year round.
Energy Facts
- During the winter, you can save as much as 2%-3% of the energy your furnace uses simply by lowering your thermostat 1°F (if it’s set between 65°F and 72°F).
- In the summer, the process is reversed. You save 3%-5% of the energy used by your air conditioner for every degree you raise the thermostat setting (if it’s set between 70°F and 82°F).
- Do you chronically forget to turn down the heat? There are low-priced, easy-to-install thermostats that adjust the temperature automatically. The simplest have built-in clocks; the more advanced models are computerized. An advanced model will, for example, turn your furnace on 30 minutes before you wake up, turn it off when you leave for work, turn it on just before you return home, and then set it for 55°F when you go to bed. Some also have a “minimum energy use” setting that monitors temperatures when you go on vacation.
Simple Ways to Save Energy
- Keep the thermostat under control. Recommended winter settings for heaters: 68°F in the daytime, 55°F at night. In the summer, turn the air conditioner’s thermostat to 78°F.
- Check the temperature. Using an accurate thermometer, make sure that the temperature near your thermostat is representative of the rest of the house. If it’s located in a drafty or sunny spot, you may be getting false readings and wasting energy.
- Plug the hole in the wall behind the thermostat with a piece of fiberglass insulation.
Excerpted from 30 Simple Energy Things You Can Do To Save The Earth, by The EarthWorks Group.
by Shana Fong on July 7, 2010
Leaking ducts can reduce the efficiency of your heating system by up to 20%. Ducts are a critical part of making your home energy efficient. If they’re leaking air – which they almost always do – or if they’re losing heat because they’re uninsulated, they’re contributing as much to global warming as they are to keeping you warm.
Energy Facts
- You can save up to 10% of your heating or cooling costs by insulating and tightening up ducts.
- Even if the air isn’t actually escaping from an uninsulated duct, you lose a lot of heat through its thin metal walls.
- When the first air that comes out of the vent after you turn on the heater is chilly, and stays chilly for a long time, you know your ducts are uninsulated and you’re wasting energy.
Simple Ways to Save Energy
If your ducts aren’t insulated: Turn on your furnace and feel for air escaping around the duct joints. If you feel any (and you probably will), hire a certified contractor such as Recurve to seal them with mastic.
If your ducts are already insulated: It’s harder to find out if your ducts leak. You can expose the joints (where the ducts bend, for instance) to check – but it’s best to leave it to an expert.
- Before you start examining your ducts, check to make sure the insulation isn’t asbestos (looks off-white, stiff, heavy cloth). If it is, stay away! It’s in your best interest to get it properly removed ASAP.
Excerpted from 30 Simple Energy Things You Can Do To Save The Earth, by The EarthWorks Group.
by Shana Fong on June 15, 2010
Americans purchase about 16 million fans each year. In the heat of summer, fans can be a good alternative to energy-sucking air conditioners.
Energy Facts
- Ceiling fans consume as little energy as a 60-watt bulb – which is about 98% less energy than most central air conditioners use.
- Ceiling fans are often used instead of air conditioning. But it’s not necessarily one or the other. Fans produce air currents that carry heat away from the skin, so even air conditioned rooms feel cooler when one is running.
- Many ceiling fans save energy in winter as well as summer. The secret: Their motors run in “reverse.” This pushes warm air caught near the ceiling down to where you can feel it. Set the fan on low speed so it pushes room air up against the ceiling, forcing warm air slowly down the walls to the floor.
- How much difference can that make? Some rooms in your house can be 15° warmer at the ceiling than at the floor. A well-placed ceiling fan can reduce this difference to only 3°.
- Remember: fans only save energy or make you feel cooler if you are in the room, so remember to turn them off when you aren’t using them.
Simple Ways to Save Energy
- If you’re shopping for a ceiling fan: Purchase an ENERGY STAR-rated unit. You’ll find them at home improvement centers. Look for a fan that’s reversible and has more than one speed. Check to make sure the blades are angled at least 10°.
- If you’re thinking about where to install one:Rooms with the highest ceilings are the best candidates. But make sure the blades are between seven and nine feet above the floor.
- Match the fan to the room. For rooms 12 feet by 12 feet or less, you can use a 36 or 42-inch fan. For rooms up to 12 feet by 18 feet, use a 48 or 52-inch fan. For bigger rooms, you may need more fans.
Excerpted from 30 Simple Energy Things You Can Do To Save The Earth, by The EarthWorks Group.
by Shana Fong on June 7, 2010
June is upon us, and for many that means starting to use our air conditioning units regularly. On an average summer day, Americans provide enough cold air to produce 16 trillion ice cubes. Check out these cool tricks to stop the cost of keeping cool from making you sweat.
Energy Facts:
- To cool your house efficiently, your air conditioner has to be cool itself. Try to keep it in the shade. An air conditioner exposed to direct sunlight will use up to 5% more energy than a shaded one.
- Air conditioners located on the north side of houses generally use less energy than those on the south or west sides, where it’s sunnier.
- If your air conditioner’s already in the sun, you can build a simple wooden shade screen for it. (But don’t block the air flow.)
Simple Ways to Save Energy:
- If you’ve got central air conditioning: Don’t close your vents. Closing too many of them actually reduces operating efficiency. Instead, reduce the air flow to unused rooms by partially closing the registers. Whenever possible, leave the room door partly open to keep the system operating efficiently.
- Turn the air conditioner off when you leave the house for several hours or more.
- A thermostat’s not a throttle, so don’t switch your air conditioner to a colder setting when you turn it on. It won’t cool the room any faster, but it will waste energy when you forget to turn it back up.
- Put a timer on your room air conditioner, or use a programmable thermostat on your central air conditioner. You don’t need to leave your air conditioner on all day to have a cool house when you get home. Hardware stores sell timers that will automatically start your air conditioner shortly before you get home. You may never notice the difference… until you see the savings on your electric bill.
- Keep the heat out. Minimize the amount of heat entering your home from outside by closing shades and curtains on hot days – sunlight coming through windows can account for 20% of your air conditioning bill. And don’t leave windows and doors open while your air conditioner is running.
- Set the thermostat as high as possible.
Caring for Coils:
You can save energy by taking care of air conditioner coils, just like your refrigerator coils. They won’t work efficiently unless the fins that cover the coils are clean and straight. So check them out every spring.
- If the fins are bent, you can carefully straighten them out with a plastic spatula. Or call a service person to repair them.
- If they’re dusty, dirty, or clogged with old leaves, you can vacuum them with your household vacuum cleaner. If the attachment on the vacuum won’t fit between the coils, blow the dirt away instead.
Don’t Forget the Filter
Air conditioners are equipped with filters to protect their fan blades, motors, and other internal parts. Replace or clean dirty filters. Dirty air filters are the #1 cause of air conditioning service calls. But filters are easy to replace and you can do it yourself. Put in a new one every month during the summer. Be sure all hardware is replaced and securely re-attached.
You may want to consider a permanent filter that you can wash instead of replacing. Some permanent filters restrict air flow too much for some units, so check first with a Recurve representative or another qualified technician.
Excerpted from 30 Simple Energy Things You Can Do To Save The Earth, by The EarthWorks Group.
by Shana Fong on January 20, 2010
Here’s a helpful checklist of things to do around the house, according to season:
JANUARY/FEBRUARY
- Clean or replace furnace filter
- Check/clean heat recovery ventilator; wash or replace filter
- Clean humidifier
- Clean range hood filter
- Check basement floor drain
MARCH/APRIL
- Clean or replace furnace filter
- Check/clean heat recovery ventilator; wash or replace filter
- Clean humidifier
- Check sump pump
- Check gutters and downspouts and clean if needed
- Inspect air conditioning; service as needed (usually every two or three years)
- Inspect basement or crawl space for signs of seepage/leakage
- Ensure that ground slopes away from foundation wall
MAY/JUNE
- Clean windows, screens and hardware; install screens
- Check that air intake and exhausts are clear of debris, nests, etc.
- Clean range hood filter
- Undertake spring landscape maintenance; fertilize young trees
JULY/AUGUST
- Air out damp basements on dry days or use dehumidifier
- For central air conditioning, clean filter in air handling unit
- Check exterior finishes
- Check exterior wood for deterioration
- Check caulking and weatherstripping, including around entry door from garage and house
- Check basement floor drain trap; replenish if needed
- Have furnace/heating system serviced (every two years for an electric furnace)
SEPTEMBER/OCTOBER
- Check fireplace and chimney; service or clean if needed
- Clean range hood filter
- Clean leaves out of eavestroughs
- Check roofing and flashing for signs of wear or damage
- Close windows, skylights
- Winterize landscaping
NOVEMBER/DECEMBER
- Clean or replace furnace filter
- Check or clean heat recovery ventilator; wash or replace filter
- Clean humidifier
- Check exhaust fans
by Shana Fong on November 24, 2009
1. Test your home’s energy IQ: Get an energy audit to determine the best roadmap to a healthy, comfortable and energy efficient home.
2. Unplug energy vampires: In the average home, 40% of all electricity is used to power home appliances while they’re turned off.
3. Insulate yourself against rising energy costs: Well-installed green insulation is the biggest bang-for-your-buck improvement you can make.
4. Get your ducts in order: In California, duct leakage accounts for a loss of 30% of heating and cooling energy.
5. Reduce, then produce: Before installing an expensive solar array, make your home a lean, efficient machine — then pay a lot less for your sun collectors.