Home Energy Audit: An Inside Story
A few weeks ago, I was approached by Bruce Wood at Sunstore Solar Solutions to perform an energy audit on their office in Greer, SC. Bruce wanted to set an example for his clients about the importance of weatherization and home performance. These guys have been successfully advocating, marketing and installing renewable energy equipment for years and I wondered what I could tell them that they did not already know. Nevertheless, I gathered up my Blower Door, Duct-blaster and digital camera and went to work.Sunstore operates in a 1200 square foot 2br 1ba brick house that is about 10 years old. You’d think a neat, little house like that would be tight and efficient- you would, of course, be wrong. After measuring the exterior and the windows and doors, I ventured into the crawlspace- a typical home energy trouble spot. Here’s what I found:
I estimated that at least 30% of the insulation was falling out of the joist cavities. This happens when moisture laden crawlspace air is absorbed by the fiberglass. The insulation simply becomes too wet and heavy to remain in place. Have you been in your crawlspace lately? If it looks anything like this, you’re throwing away your energy dollars. Make sure any exposed earth is covered with durable poly covering and that it is sealed at the seams and to the wall with mastic. It might be a good idea to consider the sealed crawlspace option. Visit www.eere.energy.gov for detailed information about air-sealing and insulating measures in your crawlspace and throughout the home.
Inside the home, I discovered additional energy problems. I noted many holes in the sturcture through plumbing and electrical penetrations. These holes and gaps added together are easily equal an open door or window, allowing conditioned air to escape and dirty, unconditioned air to rush in. These gaps are often easily sealed with caulk or foam. Explore the home improvement tab at www.energystar.gov for great air-sealing tips.
The attic, another typical trouble spot, continued the pattern. Unsealed gaps between conditioned space, improperly installed insulation and an unsealed and uninsulated attic hatch were all documented.
Remember, these folks sell solar! They are acutely aware of energy conservation measures. The audit uncovered simple, common problems that promote unnecessary energy consumption and that WASTE YOUR MONEY. When I modeled the home in my residential energy software I discovered that, when these simple improvements were made, Sunstore would reduce energy spending by as much as 20%! The repairs would also reduce harmful carbon emissions by 15%! Not bad for a day’s work…
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How To Reduce Your Energy Bills / Energy Conservation Begins at Home
Imagine leaving a window open all winter long — the heat loss, cold drafts and wasted energy! If your home has a folding attic stair, a whole house fan or AC Return, a fireplace or a clothes dryer, that may be just what is occurring in your home every day.
These often overlooked sources of heat loss and air leakage can cause heat to pour out and the cold outside air to rush in — costing you higher heating bills.
Air leaks are the largest source of heating and cooling loss in the home. Air leaks occur through the small cracks around doors, windows, pipes, etc. Most homeowners are well aware of the benefits caulk and weatherstripping provide to minimize heat loss and cold drafts.
But what can you do about the four largest “holes” in your home — the folding attic stair, the whole house fan or AC return, the fireplace, and the clothes dryer? Here are some tips and techniques that can easily, quickly and inexpensively seal and insulate these holes.
Attic Stairs
When attic stairs are installed, a large hole (approximately 10 square feet) is created in your ceiling. The ceiling and insulation that were there have to be removed, leaving only a thin, unsealed, sheet of plywood.
Your attic space is ventilated directly to the outdoors. In the winter, the attic space can be very cold, and in the summer it can be very hot. And what is separating your conditioned house from your unconditioned attic? That thin sheet of plywood.
Often a gap can be observed around the perimeter of the door. Try this yourself: at night, turn on the attic light and shut the attic stairway door — do you see any light coming through? These are gaps add up to a large opening where your heated/cooled air leaks out 24 hours a day. This is like leaving a window open all year round.
An easy, low-cost solution to this problem is to add an attic stair cover. An attic stair cover provides an air seal, reducing the air leaks. Add the desired amount of insulation over the cover to restore the insulation removed from the ceiling.
Whole House Fans and AC Returns
Much like attic stairs above, when whole house fans are installed, a large hole (up to 16 square feet or larger) is created in your ceiling. The ceiling and insulation that were there have to be removed, leaving only leaky ceiling shutter between the house and the outdoors.
An easy, low-cost solution to this problem is to add a whole house fan cover. Installed from the attic side, the whole house fan cover is invisible. Cover the fan to reduce heating and air-conditioning loss, remove it when use of the fan is desired.
If attic access is inconvenient, or for AC returns, a ceiling shutter cover is another option for reducing heat loss through the ceiling shutter and AC return. Made from R-8, textured, thin, white flexible insulation, and installed from the house side over the ceiling shutter with Velcro, a whole house fan shutter cover is easily installed and removed.
Fireplaces
Sixty-five percent, or approximately 100 million homes, in North America are constructed with wood or gas burning fireplaces. Unfortunately there are negative side effects that the fireplace brings to a home especially during the winter home-heating season. Fireplaces are energy losers.
Researchers have studied this to determine the amount of heat loss through a fireplace, and the results are amazing. One research study showed that an open damper on an unused fireplace in a well-insulated house can raise overall heating-energy consumption by 30 percent.
A recent study showed that for many consumers, their heating bills may be more than $500 higher per winter due to the air leakage and wasted energy caused by fireplaces.
Why does a home with a fireplace have higher heating bills? Hot air rises. Your heated air leaks out any exit it can find, and when warm heated air is drawn out of your home, cold outside air is drawn in to make up for it. The fireplace is like a giant straw sucking the heated air from your house.
An easy, low-cost solution to this problem is to add a fireplace draftstopper. Available from Battic Door, a company known for their energy conservation products, a fireplace draftstopper is an inflatable pillow that seals the damper, eliminating any air leaks. The pillow is removed whenever the fireplace is used, then reinserted after.
Clothes Dryer Exhaust Ducts
In many homes, the room with the clothes dryer is the coldest room in the house. Your clothes dryer is connected to an exhaust duct that is open to the outdoors. In the winter, cold air leaks in through the duct, through your dryer and into your house.
Dryer vents use a sheet-metal flapper to try to reduce this air leakage. This is very primitive technology that does not provide a positive seal to stop the air leakage. Compounding the problem is that over time, lint clogs the flapper valve causing it to stay open.
An easy, low-cost solution to this problem is to add a dryer vent seal. This will reduce unwanted air infiltration, and keep out pests, bees and rodents as well. The vent will remain closed unless the dryer is in use. When the dryer is in use, a floating shuttle rises to allow warm air, lint and moisture to escape.
If your home has a folding attic stair, a whole house fan, an AC return, a fireplace, and/or a clothes dryer, you can easily, quickly and inexpensively seal and insulate these holes.
Mark D. Tyrol is a Professional Engineer specializing in cause and origin of construction defects. He developed several residential energy conservation products including an attic stair cover, an attic access door, and is the U.S. distributor of the fireplace draftstopper. To learn more visit http://www.batticdoor.com
Energy rating is a very important part in the process of making your home or business an efficient unit for heating/cooling.
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