B7. Install Wall Insulation

Description

The purpose of wall insulation is to reduce the amount of heat that flows from a dwelling unit through the walls to the cold outside air. By reducing this heat loss, wall insulation reduces the amount of energy needed to heat the dwelling unit. Wall insulation also can save on cooling costs and reduce overheating in the summer.

A material’s resistance to heat flow is measured in units of “R-value.” The higher the R-value, the better the insulating properties. The R-value of insulation depends on the type of insulation and its thickness.

Applicability

• Single-family and multifamily buildings with uninsulated walls
• Buildings located in heating degree day zones 1.5 and above

Types

• Sprayed or blown insulation
  • cellulose
  • foams
  • blown fibers
• Rigid board
  • foam
  • fiberglass

Considerations

• A professional insulation contractor must implement this Energy Conservation Measure (ECM).
• Cavity fill insulation must be compatible with building materials.
• Cavity fill insulation should be blown in under pressure or expanded within the wall to insure even distribution.
• All materials must meet local codes.
• Exterior and interior insulating panels should be protected from impacts, vandalism, and abrasions.
• Exterior insulation panels should be protected from weather and ultraviolet radiation.
• Finish and detailing around doors, windows, and other openings should be considered so as not to detract from building appearance and operation of equipment.

Performance/Economics

• Increasing wall insulation can reduce energy costs approximately 15 to 25 percent.

Resources/Links

Energy Conservation for Housing – A Workbook, HUD, September 1998. Pages 7-29 through 7-32 address roof insulation, applications, and effectiveness.

Wall Insulation. Part of the U.S. Department of Energy's Consumer's Guide.

DOE Insulation Guidance. Information on insulation levels for existing and new homes from the U.S. Department of Energy.

Improving Energy Efficiency in Apartment Buildings, American Council for an Energy-Efficient Economy, 1995. ISBN 0-918249-23-6. Pages 96 and 97 address insulation in apartment buildings.

Consumer Guide to Home Energy Savings, American Council for an Energy Efficient Economy, 1999, ISBN 0-918249-38-4. Pages 21 through 27 address insulation methods and strategies.

The Home Energy Saver. Tool to calculate home energy use and savings opportunities.

Simply Insulate. A website of the North American Insulation Manufacturers Association that provides a variety of information about the benefits of insulating homes. Features include installation information and tools that determine the necessary insulation in your state and your projected energy savings.