Strategic Enclosure at 72Foster
We believe good design is for everyone. At 72Foster, an intergenerational affordable housing development in southeast Portland for REACH Community Development, our team thoughtfully balanced affordability, durability, and sustainability in the exterior enclosure design and detailing to meet the project’s goals for long-term operations and maintenance. By thinking outside the box of typical affordable housing design, we were able to elevate inexpensive materials to create a beautiful building that integrates into the existing community. Through attentive detailing, we were able to provide an efficient and long-lasting building that will serve residents for decades to come.
Strategic Design
We knew early on that budget constraints would require creative use of materials. We felt that for an urban building it was important to use a known urban material, brick, as a building base that would stand the test of time. Then we used cedar at important pedestrian connections—the public pass through, community room, and building entries—to soften the experience and bring warmth to public spaces. Finally, we used fiber cement at the upper levels of the building, where it wasn’t adjacent to pedestrians. We designed the window layout so that vertical stacks of fiber cement never exceeded the product’s length of twelve feet, eliminating butt joints and creating a rhythm on the exterior of the building. Orange metal window frames bring color to the building that complements but does not compete with the colourful Portland Mercado across the street, as well as create the perception of larger windows.
Strategic Detail
We worked with REACH CDC to go beyond the materiality of the building and explore different wall assembly options to create a very efficient building skin. We used effective R-value per inch as our metric for efficiency, starting with thirteen different assemblies and narrowing down to the four most efficient. We then studied each of those assemblies for their risk of water damage. Two assemblies with only internal insulation showed potential for high-risk moisture content while one assembly with exterior insulation significantly reduced the potential for moisture penetration. The chosen assembly is 2x6 wood frame with 5-1/2 inches of blown in insulation and 2 inches of external mineral wool insulation. In construction, we worked closely with the contractor, LMC Construction, to make the exterior insulation as continuous as possible.
The efficient building enclosure is a key player in 72Foster’s overall energy efficiency, along with smart choices about building siting, orientation, glazing, and the integration of technology including a 106.5 kw PV array. The rooftop array offsets energy use in the common areas and is tracked through a building management system with real time results displayed on a public screen in the lobby.
It has been fulfilling to see our collaboration with REACH become a thriving contribution to the surrounding neighborhood, while providing affordable housing for Portland. 72Foster is a perfect example of what can be accomplished when there is an alignment of values between the owner, the architect, the contractor, and the community. REACH's success with 72Foster proves that together we can make the ordinary become extraordinary.
