This home was the first home designed, prefabricated, and installed by Collective Carpentry in a line of affordable prefab-optimized home designs called Collective Homes. The owners chose to add a carport on the backside and to reorganize some of the interior living spaces to suit their love of canning and propagation, while leaving the structural building envelope design unchanged in order to optimize the design and fabrication process and cost.
The owners, two teachers, performed some of the interior finishing work themselves. Alpen high performance windows and doors were installed by Collective Carpentry. A fantastic blower door test result of .4ACH50 shows this is one airtight, energy efficient home!
Designer: Collective Carpentry (Heather Mott)
Structural Engineer: Andrew Tumason
General Contractor: Eesome Builders
Building Assembly Details
Wall panel assembly
Structural Wall: 2×6 SPF #2
Primary Airtightness: 1/2″ CDX Plywood, seams taped with Pro Clima Tescon Vana airsealing tape
Continuous Insulation: 9 1/2″ I-joist outrigger w/ densepack cellulose (R-35)
*Total finished assembly R-value: R-55
Roof panel assembly
Structural Framing: 16″ I-joist
Primary Airtightness: Intello Plus smart vapor retarder, seams taped with Tescon Vana airsealing tape
Continuous Insulation: w/ densepack cellulose (R-60)
Other Information
Blower Door Test: .34 ACH 50
This project utilized PHPP (Passive House Planning Package) modeling but did not pursue Passive House certification.
