the Vermont Street Project

Returning from a week in New York to the further progress at the site is always thrilling. I tell Val Darrah, our site foreman, that it is a big compliment to him that when I'm on the road I rarely check in. New York is very consuming now that I'm there just once a month. I don't call back too often because I don't micro-manage... unless it is needed. Few calls were made.

We mentioned in a previous post about the American Clay interiors. As with all our efforts, we look for low embodied energy in product manufacturing, an honest visual presentation upon completion, a sense of craft and reasonable value-cost ratios. We're pretty psyched about how this is working, and this is in part due to the new sprayable base coat called enjarre. It doesn't eliminate the use of hawk and trowel, but it gets a bunch of plaster on the wall quickly, to be hand floated and burnished after. Labor seems to be about cut in half, at least. On the Faswall blocks in the lower level, it might well be that this is one of the more cost-effective finishes available, for the reasons mentioned above.

There's a large disagreement between building scientists, code officials and... me, among others about the value of the vapor barrier on the inside face of the envelope. I agree that understanding the dewpoint, or the surface where condensation can occur, is critical to the life and health of the home, and to its inhabitants. My contention, particularly in this somewhat mild Portland climate, is that if vapor drive is limited by a combination of physical barrier and interior control of humidity and balanced inside-outside pressure, and there are minimal thermal bridges in the envelope system, then a wall that breathes, that is, that can take up and then give back normal variations in indoor humidity is the best approach. Cellulose insulation, protected from the outside by a continuous thermal break of rigid insulation (r-10), and allowed to breathe through to the interior, in our case using American Clay, works great.