Surrogates for Product Performance Durability? A Review of Window Warranties PDF

How long should a home last? 30 years? 50 years? 100 years? Unfortunately, builders, architects, remodelers and homebuyers have no reliable metrics for building durability and delivered long-term performance. Building products age at different rates. Many may experience dramatic changes in performance over time. Also, different performance attributes may change at different rates. For example, a product’s energy performance may change at a different rate than its structural performance. Do predictive performance models capture this variation in performance life expectation? Are a consumer’s initial product selections predicated on some expectation of delivered, long-term performance?

There are a few established surrogates for delivered long-term performance. One of the most common is building product warranty.

This study specifically investigates the chaos, confusion and contradictory claims in window warranties. Over 70 product warranties were compared as to various aspects of typical product coverages. Warranty issues investigated range from glass and hardware coverage to transferability terms, to declining and prorated coverage terms, installation coverage terms, climatespecific variables addressed and specific warranty exclusions. The financial implications of each warranty issue will be discussed from the perspective of the manufacturer, builder, remodeler and homebuyer/homeowner.

Based on a review of the literature the authors believe that this represents the first independent, non-commercial comparison of warranties for specific building products. The findings from this study should help builders, architects, consumers and others better understand the implications associated with window warranty provisions. The findings from this study should also encourage research on warranties in other building product areas where delivered long-term performance is deemed important.

Presented at Thermal Performance of Exterior Envelopes of Whole Buildings X – December 2007