DEEP ENERGY RETROFIT: AIR SEALING PENETRATIONS
At our Beechwood Deep Energy Retrofit (DER) project we are experimenting with a few different methods for air sealing penetrations. The first photo shows a neoprene flashing boot (usually used for waterproofing roof penetrations) installed around our sump pump discharge. To connect the flashing boot to the primary air barrier (Sto Gold Coat on existing masonry foundation wall), it is set in sealant. The pipe is then taped to the boot.
This photo shows the ERV intake ducting taped with 3M 8067 Flashing Tape. We have found that the 3M tape has some excellent features such as a split release backer, elasticity, and strong adhesion to most substrates.
Both methods should guarantee a long-term air seal as the boot and flashing tape are flexible and can accommodate differential movement between building components. We’ll report on how well each method worked after completing our first blower door test.