2013 11 15: the rain screen goes on first, identified by the blue stripe imprinted with delta dry, followed by the masonry wall.
2013 08 19: plywood in nailed into place over the tjis and the insulation. the burnt orange appearance is a prosoco cat 5 product. this prevents the movement of air and water through the plywood.
2013 08 19: spray on fiberglass insulation being installed between the tjis.
2013 08 16: borate is used to protect against termites. it is dyed green, i suppose so the applier can see that it has been treated. this is a relatively benign protection. the epa says:
“Borate preservatives (Disodium Octoborate Tetrahydrate or DOT) are low toxicity alternatives for protecting timber and composites from wood destroying organisms such as decay fungi and termites. They have proven effective for more than 70 years in residential and commercial construction, and their efficacy is backed by extensive field testing.
Borates are naturally occurring minerals that exist in trace amounts in rock, soil, water and all living things. Consequently, they have marginal environmental impact. Borates are also essential for plants, nutritionally important for people and key ingredients in fiberglass, glass, ceramics, detergents and fertilizers.”
2013 08 08: the pink is prosoco joint and seam filler. this forms a part of the house’s air barrier as it seals the joint between the wall’s plywood siding and the protruding wood that forms the structure that will hold the window.
demian weaver, a prosoco sales manager, has been very helpful to us in explaining and demonstrating how to use the company’s products. nice.
the pictures show the spacing of nails in the plywood that is over the wall studs. the maximum spacing of the nails is controlled by code. this is done to be sure that the house can withstand the loads from wind.
2013 08 07 the west side is looking complete, even though it’s not. the wall shown will eventually have 12″ insulation to its outside and 5.5″ of insulation to its inside. the outside of the wall that is shown in the photograph forms an air barrier or at least it will after all the seams between the plywood are taped. this along with the air barrier for the roof and the air barrier for the slab and tight windows or doors, will largely prevent air from entering or leaving the house. as a passive house, this air sealing will be tested with a blower door apparatus in which a fan will be sealed in one of the doors. it will pressurize and then de-pressurize the house. at a pressure of 50 pascal, the house may not leak more than 0.6 air changes per hour (ACH). just a few years ago, this was thought to be an impractical standard; but passive houses regularly achieve better than this. many houses will leak at a rate more than 10 times 0.6 ACH.
pascal is a metric unit of pressure that has somehow made it into the world of english units that are used almost exclusively in residential construction. 50 pascal is 0.00725 pounds per square inch. .
2013 08 06: progress is fast with walls and a roof that are factory built. the windows are larger than i would have thought from the drawings. nice.
2013 08 05: more walls are erected. some roof trusses are installed