Increased Scrutiny for Air Infiltration

Paul R. Gary
May 13, 2011
COLUMN : Legal

Something's in the air. Years of increasing fenestration product thermal performance requirements–more recently coupled with on-again, off-again financial stimuli directed to improving “whole house” energy performance–is elevating air infiltration to a new level.  Air infiltration could potentially join water penetration as a major source for legal claims against window and door companies. 

It is easy to envision a day when whether applying for a loan or a rebate or selling a home, an “energy score” will be right up there with the number of baths. In some parts of the country, home performance contractors already do blower door tests as part of the energy efficiency assessments of homes.

It is unclear how all this will develop and evolve. It is a short hop, however, from a neutral evaluation to the suggestion that something is “wrong” with the energy performance of a home, including the fenestration components that appear to be contributing to a poor score. The concept of “defect” is destined to gain a new dimension; this one lacking any requirement for a readily observable consequence. The question will be asked: “Who is going to pay to fix this?”  The easy target will be the manufacturers of components that made energy-related representations in connection with sale of their products.

Air infiltration is the nemesis of thermal performance and energy conservation. The more air moves between outside and in or inside and out, the greater the transfer or loss of energy from conditioned to unconditioned space. Yes, certified fenestration products have air infiltration ratings. To achieve these, standard testing protocols are used.

But, manufacturers will face challenges if the air infiltration performance of installed products fail to meet consumer expectations. Or, more specifically, the companies performing the evaluation on behalf of those consumers. For those who have been swept into construction defect claims due to allegations surrounding water-resistance performance, this may sound all too familiar.

Claimant attorneys are more than willing to take the opportunity to try to re-characterize a window's air infiltration certification to be a source of product liability long after manufacture.  That is already evident with respect to water performance. The drop in overall new construction has put a “bubble" in the pipeline for these attorneys. Their motivation is high.

There are tools to manage most every problem. It's little surprise that it comes down to what a window company says and it does. What you say about your product and how your company is positioned in this area matter, a lot. It is time for manufacturers and installers of fenestration products to manage this situation.

Slowed by current funding limitations–but not defeated–the pursuit of energy conservation in our buildings and the dream of an energy independent America are inexorably linked. To read the pronouncements of those legislators visiting window companies over the past few years, there is apparently no better way to stimulate the economy and save money at the same time than upgrading our homes and other buildings.

This is all good. We want and need energy efficient buildings, but experience shows that well-intentioned programs get out of control. Efforts to assist owners in establishing the energy performance of their existing or prospective homes and commercial buildings can be a positive for the industry, but the devil will be in the details.

Paul R. Gary is the prinicipal of The Gary Law Group, a law firm based in Portland, Ore., emphasizing legal issues facing manufacturers of windows and doors. He welcomes feedback about articles published in Window & Door and can be reached at 503/227-8424 or