With the foam sprayed in and Fi-Foil in place, Two Trails sustainable building consultants came in to take a look
Owens Construction's Flagstaff project was a huge spray foam job, especially the 16/12 great-room roof. One of the side benefits of closed cell foam is that it becomes quite rigid and adds to the frame’s stiffness. The applicators were careful not to spray more than 3 inches at a time, to avoid any unwanted exothermic reaction. Fortunately, drying time is less than an hour, so they could make another pass the same day.
Two Trails sustainable building consultants were on hand after the foam installation and in the middle of application of the Fi-Foil hybrid insulation system. They cut open the Fi-Foil to verify the foam behind, pointing out the seamless application over the first-floor rim joist and down onto the foundation walls. This strategy creates a tempered crawlspace, which will have both heat and ventilation.
The Owens Construction team also foamed the roof in the attic over the second-floor bedrooms, instead of relying on blown-in fiberglass on the attic floor. This was done so that the same amount and type of insulation is in the attic portion as is in the cathedral ceiling portion, preventing thermal “nosebleeds."
Two Trails will conduct a blower door test when the project is near completion in order to depressurize the structure and measure air infiltration. As mentioned in a prior post, Bill Owens has installed three Panasonic air to air heat exchangers to guarantee good air quality. For this climate zone, the International Energy Conservation Code (IECC) allows a maximum of three air changes per hour at 50 Pascals. The tighter the house, the lower the heating bills, resulting in a more comfortable the house is and a lower chance of mold or rot with better control of moisture in walls.