Air bubbles out through plywood during a preliminary blower door test performed on a rainy day. Leakage exceeded Passive House allowable levels because of the air permeability of the building's plywood sheathing.
An early blower door test of the Wayland house revealed that the structure's plywood sheathing leaked air. With rain soaking the plywood and positive air pressure applied inside the hose, major air leakage created obvious bubbles on the plywood skin.
A view of the Siga Majcoat waterproof breathable membrane roof covering, sealed with Siga Wigluv tape.
The crew applied Siga Majcoat air-tight membrane to the entire roof, including the octagon turret roof, and sealed all the joints with Siga Wigluv tape.
The crew wrapped the entire house wall with Siga Majcoat waterproof, vapor-open fabric. Majcoat rolls were long enough to allow covering the entire perimeter with only two vertical tape joints.
Carpenter Tim Houldcroft cuts out a window opening in the membrane-covered wall.
Carpenters Tim and Casey work on a window opening prototype in the Passive House wall.
Carpenters Casey and Tim install a Unilux Passive House window in the punched opening.
A closer look at the Siga Wigluv tape air-sealing detail around the window buck.
The Auburndale team is attaching Roxul rock wool insulation to the walls and roof of the house using a system supplied by Ramset. Here, a carpenter prepares to insert the long driver pin into the hollow fastener tube.
The carpenter uses a Ramset gas-fueled fastening gun to drive spiral-shank nails through the pointed end of a plastic tube fastener.
Using a Ramset T3 InsulFast gas-fueled gun, the crew applied six inches of Roxul rock wool insulation over the air-tight, vapor-permeable Siga Majcoat membrane.
Here's another look at the roof insulation job in progress, showing staggered courses of 2-foot by four-foot, three-inch-thick Roxul rock wool insulation batts.
The roof, face, and cheek walls of the dormers were also insulated with six inches of Roxul rock wool.
Another look at the Roxul rock wool insulation on the dormers during installation.
Framers apply vertical 2x6 strapping over the Roxul rock wool insulation, to create an air channel under what will be the sheathing for a slate roof. The uninsulated portion of roof at left will be the location for a skylight.
A framer uses long GRK structural screws to attach 2x6 strapping for the structural deck for a slate roof.
A framer nails steel straps onto the 2x6 roof strapping, to connect the strapping across the roof peak to strapping on the opposite side of the roof.
A framer installs metal strapping across the 2x strapping at the roof hip, to strengthen the roof against wind uplift loads.
Carpenter James Stewart applies Pittsburgh Corning PC 99 sealant to the joints between pieces of Foamglas insulation around the house perimeter. High load bearing "HLB" Foamglas will support the brick veneer cladding at this location, but the Foamglas has to be thoroughly waterproofed because of its vulnerability to freeze-thaw damage.