While most homeowners realize the importance of conserving energy, few truly know how efficient their homes are. Appliances and cars are ranked for their efficiency; homes are not.
But, they can be graded-via the EnergyWise Homes of Illinois Home Energy Rating System, conducted by the Illinois Department of Energy and Natural Resources and the University of Illinois’ Small Homes Council/Building Research Council. It’s a fairly complicated energy audit, though, that needs to be administered by an independent contractor.
The authors of the EnergyWise program, however, have offered us a more simplified examination of your home’s efficiency-a way you can grade your home yourself. Although this test is fairly basic, it should provide a good gauge for determining how energy-efficient your home is.
Attic insulation
The first category to be measured is attic insulation. “Attic insulation is as crucial as putting your hat on before you go outside on a cold day,” says John Marley, a mechanical engineeer for the Illinois Department of Energy and Natural Resources in Springfield.
Start by using a ruler to measure the depth of any insulation in the attic floorboards. If you have no insulation, score 0 points. If you have three to four inches of insulation, which offers an R-value (the degree to which the insulation resists heat loss) of about 11, score 3 points.
For six inches on insulation (R19), score 5 points; 8 points for 10 inches of insulation (R30); and 10 points for 12 to 13 inches of insulation (R38 to R49).
Wall insulation
Next, gauge the insulation in your home’s exterior walls. This can be done by removing covers from wall switches or outlets.
If you have two-by-four framed walls with no insulation, score 0 points. If that same wall has insulation, score 5 points.
If you have a newer home with two-by-six framed walls with insulation (R19), score 8 points. Add 2 points if you have R15 fiberglass batts and insulated sheathing on the exterior of the wall system.
Deduct 2 points, however, if you have an unheated basement or crawlspace, and insulation on the interior or exterior of the walls. “You can lose a lot of heat through basement and crawlspace walls, despite being well insulated above,” says Marley.
Windows
Next, inspect your windows. If you have single-pane windows with no storm windows, give yourself 0 points. Score 2 points for single-pane windows with storm windows, and 3 points for wood storm windows.
Score 5 points for double-pane, insulated glazing windows, typical of new construction. Score 7 points for triple-pane or double-pane windows with storm windows. If your home has double-pane windows covered with a low-emissivity, or Low-E, coating (which helps prevent heat loss on the cold days and admits light but filters out heat gain), with argon gas, tally 8 points.
If you have the top-of-the-line, double-pane, heat-mirror windows with krypton gas, score 10 points.
Add 1 point if more than half of your home’s windows face south, which add heat to the home in winter.
If you score low in the window category, however, new windows aren’t necessarily the answer. “New windows are a major investment and the payback period may be over many years,” says Marley. “I would instead invest a few dollars to weatherstrip, reglaze and caulk the older windows.”
Air leakage
Next, rank your home’s infiltration characteristics, the air leakage from cracks and crevices.
If the house feels drafty and you can physically feel slight breezes around doors, windows and wall outlets, score 0 points. Especially look for drafts on the north and west sides of the house, where the winter winds can be felt. Score 5 points if those drafts are stopped by storm windows and weatherstripping.
If your home was constructed within the last five years and the contractor used a house wrap on the exterior, caulked around pipes and electrical conduits, score 8 points.
Score 10 points if the contractor went as far as to use a blower door, a fan-like device that moves air through the house, allowing the contractor to seal cracks and crevices.
Also, if the house has casement-style windows, add 1 point because they seal better than double-hung windows. Add a point if you also live in an urban area where homes act as a windbreak for each other.
Deduct 1 point, however, if you have recessed canister lights in your ceilings, especially those ceilings below an attic. Heated air escapes through those openings. Also, deduct 1 point if you have a whole house fan installed in the ceiling that’s not well sealed.
Another 1 point deduction is a fireplace without glass doors or a working damper. “Fireplaces are for aesthetics only,” Marley says. “They’re not good for heating a room.”
Heating system
You can also gauge your home’s heating system. Score 1 point if you have the highly inefficient old gravity or octopus furnaces, which use air movement to heat a house.
If you have a natural gas, forced-air furnace that was installed before 1980, score 3 points. Score 4 points if you have a steam or hot water boiler installed before 1990. If you have a post-1980 gas forced-air furnace with a standing pilot (which remains constantly lit), or a home with electric baseboard heating, score 5 points.
If you have a modern natural gas, forced-air furnace with direct venting and instant ignition, score 7 points. If you have a steam or hot water boiler that was installed after 1990, score 8 points.
If your home has a gas-condensing or condensing-pulse furnace, score 9 points. These furnaces burn fuel more efficiently than other designs and minimimize heat loss through flue exhausts. Score 10 points for an electric or gas heat pump, the most efficient type of heating plant.
Deduct 1 point if you have not had the system cleaned, adjusted or serviced by a professional in the last few years.
Ductwork
Inefficient ductwork can cause uneven heating of rooms and higher energy bills. “Plus, if the ductwork has air leaks and runs through an attic above the insulation, you’re losing valuable heated air into the attic,” Marley adds.
The worst-case scenario is when ducts are not sealed or insulated, and run through an unheated attic, garage or crawlspace. Score 0 points.
Score 3 points for ducts that are insulated but not sealed, and running through an unheated space. Score 5 points if they’re not sealed or insulated but running through heated areas.
If the ductwork is insulated and sealed and runs through unheated areas, score 7 points. Score 10 points if sealed and running through heated areas.
If you have a boiler instead of a forced-air furnace, give yourself 3 points if sections of your radiator pipes run through unheated parts of the house, 5 points if they run through heated parts of your house, and 7 points if you have insulation on the pipes.
Water heaters
If your home’s water heater is more than 15 years old, score 2 points. Score 5 points for a high-efficiency and insulated gas or electric unit, and 10 points if your water heater is hooked up to an electric or gas heat pump.
Add a point if you have an older model but have covered it with an insulation blanket. Deduct a point if the unit is in an unheated garage or basement.
Air conditioning
An air conditioning system is considered a luxury, not a necessity. As a result, score 10 points if you don’t have one, or if you have a high-efficiency heat pump.
If you have a high-efficiency, regularly maintained central AC system, score 5 points. Score 5 points if you have newer window air conditioners that are used judiciously.
If you have a central air system older than 10 years, score 2 points. If you have older window units in south windows with little weatherstripping around them, score 0 points.
Give yourself 1 bonus point if you use ceiling fans with your AC system, or if you have a zoned central air conditioning system.
Bonus points
Your home scores a couple of bonus points if you have a setback thermostat for both heating and cooling purposes; if you use high-efficiency lighting, such as fluorescent lights versus incandescent bulbs; and if in the summer months you use awnings or overhangs, or have deciduous trees, to reduce the load on the your home’s air conditioner.
Score 1 additional point if you have low-flow showerheads and faucet aerators. They conserve water and energy to heat the water. Add 1 point if you have a low-flow toilet and insulation on your hot water pipes.
Also, score 1 point for newer appliances, which use less energy. Finally, score 1 point if you use the appliances efficiently, running only full loads, cleaning clothes with cold water, and letting dishes air dry.
Tallying the score
If you scored under 25 points, your home is highly inefficient energy-wise, and major dollars can be saved each month by making improvements. If you scored between 25 and 34 points, there is still room for improvement.
If you scored between 35 and 45 points, your home is average. “You can make changes but they need to be thought out carefully so that you get the best return for your investment,” Marley says.
If you scored between 46 and 64 points, you have a better than average home and most of the improvements you can make are lifestyle changes-shutting off lights, using a setback thermostat, running only full loads in the dishwasher, etc.
Finally, if you scored between 65 and 90 points, you have a highly energy-efficient home. “You should proud of yourself-and your home builder,” Marley says.
———-
For more information about home energy conservation or the EnergyWise Homes of Illinois audit, contact the University of Illinois’ Small Homes Council/Building Research Council at 217-333-1801 or the Illinois Department of Energy and Natural Resources at 217-785-2007.
