Structure

Windows | Attic Fans | Wall Insulation | Duct Insulation

Energy Usage Chart

Windows

Energy Tip:
Upgrade leaky windows. Consider replacing them with energy-efficient models, or boost your present efficiency with weather-stripping and storm windows.

Operating Expense:
Windows in older homes can cause up to a third of the home's total heat loss. In newer homes, windows typically account for 15% to 40% of total heat loss. Windows can also account for as much as 75% of heat gained during the summer months, adding to air conditioning costs.

Proper Selection & Buying Tips:
Windows are offered in wood, aluminum and vinyl frames. Wood and vinyl are better insulators than aluminum. Wood frames are more expensive than aluminum and vinyl. In addition to the frame material, the thermal performance of the window will be affected by the following:

• Glazing: Double glazing insulates almost twice as well as single glazing. Adding a third or fourth layer results in additional efficiency gains.
• Thickness of air space: The air space between double panes of glass in a double-glazed window has a major impact on the efficiency performance. A very thin air space does not insulate as well as a wider air space. An air space of up to 1" is good, beyond that efficiency gains cease.
• Low conductivity gas fill: Heat loss can be further reduced by substituting the air between the panes of glass with denser lower conductivity gas such as argon, carbon dioxide, sulfur hexafluoride, etc.
• Tinted glass coatings: There are a variety of tinted glass and films available . These new glazing reduce the solar heat gain without reducing visibility.
• Efficiency: In 1993 the National Fenestrating Rating Council began rating window performance to allow for comparison and evaluation of windows. Windows with NFRC- ratings will carry a u-factor which will allow for efficiency comparisons. The lower the u-factor the better the overall insulating value of the window.

Attic Fans

Energy Tip:
A cooler, well-ventilated attic will reduce cooling costs.

Operating Expense:
If running all the time, a 24-inch electric attic fan costs about $7.30 per month to operate.

Buying Tips:
There are three types of attic fans available for the residential homeowner. Some are wind powered, others are electronic and feature either manual or automatic thermostat controls.

• Turbine attic fans are mounted on top of the roofs and are powered by the wind. Installation requires cutting a hole in the roof.
• Gable power attic fans are mounted to an attic gable. These types of fans are typically activated by a thermostatic control.
• Attic roof ventilators are powered by electricity and are thermostatically controlled. Installation of these vents require cutting a hole in the roof to allow for mounting.

Selection:
Determining the proper type of attic fan is a function of the availability of electricity and the existence, location and size of vent gables. If the home has electricity in the attic and adequately sized gables all three types may be options.

Sizing:
The size and number of the attic fans required is a function of the square footage of attic space. Electronic gable vents and power ventilators will state the amount of square footage they are capable of venting.

Use buying guides such as Consumer Reports, Consumers Guide to Home Energy Saving, etc. for insights into quality and reliability.

Wall Insulation

Energy Saving Tip:
The majority of the heat loss in a home is through the roof, so make sure your attic has the recommended amount of insulation.

Installation Expense:
As a homeowner, you can save between 30% and 45% of the cost of insulation by installing it yourself rather than hiring a contractor. Listed below are approximate costs for various types of insulation. Compare the differences between "do-it-yourself" and having a contractor do it.

Insulation	Do-It-Yourself	Contractor-Installed
R-11	$.17 sq./ft, or $17 per 100 sq./ft	$.25 sq./ft, or $25 per 100 sq./ft
R-19	$.29 sq./ft, or $29 per 100 sq./ft	$.50 sq./ft, or $50 per 100 sq./ft
R-30	$.46 sq./ft, or $46 per 100 sq./ft .	$.75 sq./ft, or $75 per 100 sq./ft
NOTE: The above costs are based on faced-insulation.

Insulate attics to R-30 standards
Insulate exterior walls to R-13 standards
Insulate crawl space to R-19 and basement ceilings to R-11

Efficiency:
Insulation is rated by R-values and expresses the resistance to heat. The higher the R-value the better the insulating power.

R-values are clearly marked on all types of insulation. The most common R-values for insulation are R-11, R-13, R-19, R-25, R30, and R-38. The R-value for loose or blown in insulation can only be determined after insulation has been installed.

Buying Tips:
The most common type of insulating material for homes is mineral fiber and cellulose. Mineral fiber is the most common and versatile insulation and is available in three forms: Rolls or blankets of insulation with or without vapor barriers. Batts are similar to rolls however, they come in 4 or 8 foot lengths. Blown in loose insulation utilizing pneumatic equipment insulation can be blown into ceilings or walls. Cellulose is made from scrap paper and is usually blown or poured into place.

Selection:
The type of insulation and the thickness depends on the area requiring the insulation, the building's construction and the amounts of insulation currently in place.

Blown-in cellulose and fiberglass are typically used to insulate the walls in existing homes or areas with limited access. Batt and roll insulation is very common in new construction where access is easy.

Homeowners Note:
DO NOT compress insulation. Much of the value will be lost if compressed.

Duct Insulation

Energy Saving Tip:
Insulate your ducts. Heating experts estimate that 99% of all American houses with central furnaces or air conditioners have leaky ducts. You can save up to 10% of your heating or cooling costs by eliminating those leaks. Seal all joints and seams with quality duct tape or mastic.

Installation Expense:
Installing R-4 duct insulation costs about $14.50 per 6 linear feet of fully insulated duct work, or $290 per 120 linear feet of fully insulated duct work. Contractors currently charge about $450 to completely insulate 120 linear feet of duct work.

Efficiency:
Insulation is rated by R-values and expressed in terms of resistance to heat. The higher the R-value the better the insulating power. The R-values are clearly marked on all types of insulation.

Proper Selection:
The type of insulation installed is a function of the homeowners preference however, the insulation should have a minimum R-value of 4.

Buying Tips:
There are several types of insulation which can be used to insulate ducts passing through unheated spaces:
• Standard foil faced fiberglass insulation.
• Vinyl-faced insulation made especially for ducts.
• Ridged foam insulation

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