Monday, May 3, 2010
ZEH Virginia, its all in the little things
Building a green ZEH is not one big thing, but a series of many little things. Our builder is using AdvanTech subflooring, a product offered by Huber with a 50 year guarantee that shows significant improvement over both OSB and plywood in stiffness, strength and water resistance, while using no added formaldehyde and meeting the Sustainable Forestry Initiative (SFI) Standard. This produces stiffer, quieter floors while minimizing outgassing. The piece of light blue material you see sticking out from the block in the lower picture is a foam gasket that serves as an air sealing measure along the uneven block and brick. It also is a moisture break to keep water from migrating to the wood from the foundation. The aim of maintaining an extremely tight "envelope" with respect air and moisture infiltration is a guiding principle that directs innumerable building product choices and practices when constructing a zero energy home. Mark, our builder, is shooting for the lowest HERS rating house in Virginia, so each of these decisions is made with efficiency and best practice in mind.