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  Owens Corning

The products in our Insulating System are designed to reduce the natural movement of heat from warmer to colder areas. Other Insulating System components work to control moisture and assure proper ventilation. (Insulation even helps to control noise in your home. Find out how in the Noise Control section of our web site.)

Reducing heating and cooling costs

A poorly insulated home requires an inside temperature at least 3° higher to maintain the same level of comfort. A properly installed Insulating System protects your home with a thermal retarder that helps reduce costly fuel bills during heating and cooling seasons.

Reducing air infiltration

According to the U.S. Department of Energy (D.O.E.), "Before you insulate, you must control air leakage." Reducing air infiltration takes the strain off your heating and cooling units, so they don't waste energy by running longer than necessary. The result can be annual energy-cost savings of up to 10%.

Cold, windy days are the best time to check for air leaks. Simply attach a piece of tissue or light paper to a string. Then bring it right up close to areas where you suspect air is getting in or out of your home. If the tissue moves, you've found a leak. Problem areas include the space around doors and windows, where plumbing and electrical wiring comes through walls, floors and ceilings.

Controlling moisture

Showers, cooking, washing and even breathing can put a surprising amount of moisture into your home—from 5 to 10 pounds a day! Washing and drying clothes indoors can add another 30 pounds. In the winter, any moisture that passes through to these surfaces can accumulate and condense on the cold inner sides of exterior surfaces. Eventually, this condensation may blister the outside paint, form stains on drywall ceilings or walls, or even damage your home's structure.

Vapor retarders help control the amount of moisture passing through insulation and collecting inside exterior walls, ceilings and floors.

Ensuring proper ventilation

When your attic or crawlspace is properly ventilated, a positive air flow is created which allows the house to breathe and helps prevent moisture build-up.

In hot weather, proper ventilation prevents the attic from becoming a hot box and transferring unwanted heat down through the attic floor (even if the attic is insulated) into the living area. In cold weather, proper ventilation helps prevent moisture from condensing on the insulation, structural wood and the underside of the roof deck.

If attics/flat ceilings and crawlspaces are not properly ventilated, problems with moisture are likely to develop. To help an attic and crawlspace breathe, we recommend:

In the attic
Eave vents openings under the eaves—combined with roof vents or gable vents create positive movement of air out of the attic. Always provide at least two vent openings, allowing air to flow in one and out the other.

As a general rule, one square foot of free vent area per 300 square feet of attic floor area is recommended when a vapor retarder is used. In situations where no vapor retarder is used, one square foot of free vent area should be provided for each 150 square feet of attic floor area.

In a crawlspace
Providing at least two crawlspace vents will allow a positive flow of air in and out of the crawlspace. One square foot of free vent area is recommended for every 1500 square feet of floor area covered with a polyethylene vapor retarder (every 150 square feet if there is no vapor retarder). In crawlspaces that are unheated and/or that have a dirt floor, it is also recommended that the floor be covered with a polyethylene vapor retarder.

To learn more about ventilation and locate the right ventilation products for your project, check out the complete Owens Corning Ventilation System portion of our site.