Siding Retrofits: A Golden Opportunity to Boost Envelope Performance

With most residential siding products lasting 20 to 40 years, re-siding opportunities don’t come up that often but when they do, they offer a golden opportunity to improve the envelope performance of the home. With the old siding peeled off, contractors can see inside the walls to fix what’s damaged and add what’s missing. What’s often missing is good cavity insulation, air sealing, weather barrier, and flashing; and almost no older homes have continuous rigid insulation over the studs or sheathing. Re-siding jobs also offer a cost-effective opportunity to upgrade or replace existing windows and to properly integrate the window flashing with the walls’ air and water control layers. Building scientists from PNNL, Building Science Corporation, and Earth Advantage teamed up with builders and contractors on five re-siding and window upgrade projects in five different climate zones around the country to come up with cost-effective workable approaches for adding rigid insulation and window upgrades to siding replacement jobs. This presentation discusses conditions encountered, alternatives proposed, and solutions achieved as the teams worked their way through the retrofit process on homes with a variety of existing siding and windows. We’ll present lessons learned and specific retrofit details of each project.