THE FACTS ABOUT AIR INFILTRATION

Does insulation help reduce air infiltration?
Fact:  The primary role of wall insulation is to thermally insulate.  The air flow resistance of wal insulation is if little benefit to the overall energy performance of a house.  Therefore, wall insulation plays an insignificant role in reducing a new home's air infiltration if modern house construction practices are followed.

Where does air infiltration occur?
Fact:  Let's start by looking at what areas of a house are most likely to allow air infiltration.  It's been calculated that over 95% of air infiltration in a new home is from non-insulated sources.*  Air infiltration primarily occurs at windows, doors, fireplaces, perimeter joints, and ductwork penetrations between conditioned and unconditioned areas.  Wall outlets, which contribute less than 5% to whole house air infiltration, are the primary insulated source of infiltration.  And through the simple use of wall outlet gaskets, even that small percentage of loss may be reduced to zero.*

What helps reduce air infiltration?
Fact:  Careful design and selection of building materials, along with good workmanship, can significantly reduce a new home's air infiltration rates.  Building materials such as building wraps and polyethylene vapor barrier films are specifically designed and installed to reduce air infiltration.   And, good building practices, such as limiting the number of perimeter joints, use of caulking between the sill and plate, caulking around window and door framing, and the use of weather-stripping around doors and windows, are the most widely used and proven means of reducing air infiltration.  All these materials and practices are part of a "system" approach to reducing air infiltration.

High-Performance Fiberglas batt insulation products deliver high thermal performance.
Fact:  Factory-made batt insulations have been used effectively and with great reliability for over 50 years.  In fact, Owns Corning, as a quality-conscious batt insulation manufacturer, contracts with the NAHB (National Association Of Home Builders) National Research Center, Inc. to conduct monthly inspecions and thermal testing of our Fiberglass batt insulation products.  This NAHB Certification is further assurance that Owns Corning's R-13 Sidewall Batt Insulation and high-performance R-15 and R-21 Sidewall Batt Insulation will consistently provide the claimed thermal performance

Using Fiberglas batt insulation products in conjunction with caulking and weather-stripping materials and good building practices are reliable methods to keep a new house thermally efficient.

*Based on information contained in the 1989 ASRAE Handbook of Fundamentals, Chapter 23 on infiltration.