Provide educatio insulati

ll/l'ANY know the value of adding insulation to a home IYIto save on energy costs, but few know what R-value to buy or how much, or whether a vapor barrier is needed and, if so, which one. Choices can be quite intimidating for consumers and contractors; dealers can help by understanding a few basic construction principles, according to insulation manufacturer Johns Manville.

First, the resistance to heat flow through radiation, conduction and convection in a building is measured in R-values. The higher a material's R-value, the greater its insulating power. R-values are marked or identified on batts and rolls of insulation, as well as on its packages. Colorful charts show the number of bags, thickness and weight needed per 1,000 sq. ft. to achieve a certain R-value.

To aid do-it-yourselfers and professional contractors in selecting the correct R-value for their area, building products retailers generally post a chart of recommended R-values for five temperature zones across the United States (see below). The R-values represent the North American Insulation Manufacturers Association's recommendations for optimum thermal performance for average climate zones shown on the map.

Vapor barriers, more accurately called vapor retarders, are also crucial in blocking air filtration through walls, ceilings and floors; although its primary purpose is to control moisture. Typically, a family of four produces about 10 lbs. of water vapor per day.

Vapor barriers minimize the amount of interior moisture that passes into the walls and attic. Without effective vapor retarders, mold or mildew can occur and structural components of the building can be damaged. Insulation also can be dampened, temporarily reducing its effectiveness.

Vapor retarders are installed on the warm side of walls, ceiling and floors. This means that in ceilings, the vapor retarder faces down, in walls it faces the inside, and in floors over unheated spaces, it faces up. With the exception ofreverse-flange insulation, the stapling flanges are on the same side as the vapor retarder. In hot climates, however, where air conditioning is used more than heating, the exterior side of the insulation is often the warm side. In

The higher a material's R-value, the greater its insulating power.

these situations, local construction practices should be followed regarding the use and placement of vapor retarders.

In some construction, separate vapor retarders are used. When required, 4-mil or thicker polyethylene sheeting, available in rolls, is rolled out horizontally and stapled to the warm-in-winter side of the framing. The polyethylene should be stapled at the sides and the excess material folded back into the room. If more than one sheet of polyethylene is required, a double fold should be made at the meeting of the two pieces and stapled, or the sheets may be overlapped and taped. If stapled, the pieces should meet only at a stud or a joist. Foil-packed gypsum board also serves as an effective vapor retarder.

During a time of critical energy supply and constantly rising fuel and energy costs, fiberglass insulation and vapor barriers reduce energy consumption in winter and summer by reducing heating and cooling costs.

CHEMOI\IITE/ACZA consistently meets building code standards for treated wood. CHEMOI\ITE/ACZA is the only waterborne pressure treatment available to penetrate Douglas-fir up to 250 pcf to assure structural integrity and compliance with ATilVPA Standards.

State and local building officials are on the lookout for insufficiently treated Douglas-fir lumber resulting from misinterpretations of the A\7PA Standards.

V*** ruXX$TtrXXU, exx&x F** EtrE xfr$FR&TX$t IX&.

Look for the quality mark of an accreditedAlsc inspection agency to insure that you using the right application for the job.