Project overview

This proof of concept home uses a bare-bones structure to shape luxurious, warm, and bright spaces. We designed it to define what ‘high-performance’ means for us: maximal efficiency in material and energy use, low carbon footprint, affordability, and longevity.

Design criteria

Concept

We developed what we call a 'tight frame' structure to use significantly fewer resources than traditional framing. Taking advantage of dimensional efficiencies, the 4' on-center post spacing reduces waste and accelerates construction. To maximize a small footprint, this is a three-story, three-bedroom home. The high-and-tight volume takes advantage of a view by perching the living space on the top floor with a ribbon of venting windows and vaulted ceilings.

Site

The site slopes up to the Roslyn Urban Forest. This adjacency to recreational access also demands support of local wildland fire prevention efforts. We re-mulched the soil after construction to encourage existing plants, volunteers, and newly planted drought-resistant natives to thrive. No fence around the property invites the local deer, elk, bear, turkey, and cougar to seasonally travel through as they always have.

Materials

Joining a Tight Frame structure with a PERSIST envelope allows materials to serve multiple capacities; for example, plywood is both exterior sheathing and the interior finish. Thick, continuous, exterior wood-fiber insulation (also a carbon sink) is fastened back to structure with strapping, which serves as additional lateral strength and provides a ventilation cavity behind the Accoya board and batten siding. A corrugated galvalume roof completes the robust envelope and holds an 11kw solar array. We keep air quality high with low-VOC, natural, and non-toxic materials, heat-recovery fresh-air ventilators, and operable triple-pane windows. Hot water generated by an air-to-water heat pump circulates through low-pressure, low-flow radiators to keep the home warm.

Build

As our prototype, we seized the opportunity to build ourselves: we completed much of the envelope, interior building, and finishing work, while we leaned on professionals for scopes like foundations, plumbing, and electrical. We invited our friends at Treecraft Design Build to prefabricate, erect, sheath, and weatherproof the Tight Frame structure in two weeks with their four-person crew. We specified steel cleat and dowel fasteners to make connections strong and efficient.

Credits