Tuesday, June 23, 2009

Tight as ... Tupperware

Back in the late 1970s, my mother hosted at least one Tupperware party that I remember. The advantage of Tupperware is the airtight seal. Little did I know then that you want the same thing from a house.

I've been spending a few days on and off over the last few weeks airsealing around the house: mostly where the concrete meets the mud sill, and where the CEB wall meets the top plate. All you need is a caulk gun, a LOT of caulk (I used a GE product, Silicone I, but any silicone-based caulk will work well), and off you go. Believe it or not, this is one of the most energy efficient things you can do to your house (move over, replacement windows!) - so efficient in fact, that EarthCraft standards mandate airsealing in lots of places. Most of them I've covered now - for the rest of the airsealing (and firestopping), the professionals from Southland Insulators will take over before they apply sprayfoam insulation to our roof, the clerestory window area, and the bandjoist. More on that in a future post.

For now, just a picture of a nice, thick, bead of Silicone caulk between the top of the CEB wall and the top plate. Often under-appreciated, but such an important component of building green.

EIFS, Act 2

I'm blogging today instead of Mike - he's away.

Claudia and her EIFS crew wrapped the house in extruded styrofoam today. (Yes, there are different kinds of styrofoam: expanded - the white, bubbles-pressed-together looking kind; and extruded - which is much smoother in texture.) The advantage of extruded styrofoam is that (a) it has a greater R-value (R-5 per inch ... we have three inches, so a total of R-15) and (b) it is a water barrier (by contrast, expanded styrofoam is about as permeable as a sieve).

For now, the house looks like a big freezer box. The next few steps are to sand the styrofoam smooth; embed a nylon mesh in another scratchcoat, and then to apply the final EIFS coat. In a week, weather permitting, we should have the final product.