Category Archives: wall

borate is applied to the walls

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.”

a section of wall after treatment with borate

a section of wall after treatment with borate

tjis going on

tji stands for truss joist i-beam. these are usually used to support floors or roofs. some passive houses, including old hopkins road, use them to define space for insulation. blown in high density fiberglass will soon fill in between the tjis shown below.

IMG_0445

pink air barrier

2013 08 08: the pink is prosoco joint and seam filler. this forms a part of the house’s air barrier as it ┬áseals 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.

prosoco joint and seam filler, it's pink!

prosoco joint and seam filler, it’s pink!

nails

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.

west wall

west wall

 

 

 

 

 

 

 

 

close up of the west wall under a window

close up of the west wall under a window

 

 

 

 

 

 

 

a closer close up showing nail spacing

a closer close up showing nail spacing

 

 

 

 

looking nice

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.┬ámany 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. .

the west wall looking complete

the west wall looking complete