Many of the purported advantages associated with modular wood-frame construction compared to traditional stick-built framing are generally well accepted in the industry: increased quality control, indoor construction, shorter project schedules, ability to service remote locations, and in some cases favorable labor and material pricing. Despite all of these advantages, special attention needs to be given to the integration and assembly of the building enclosure components, both within and between building modules, to ensure that the performance of these modular buildings meet the expectations of all parties involved. This paper will focus on the building enclosure functions of heat, air, and moisture control in wood-framed residential buildings, and will apply these concepts to the realities of modular construction.
Specifically, this paper will detail lessons learned through design and construction of two recently completed modular construction projects. The first project is a multi-unit dormitory located in an isolated northern climate and incorporates super-insulated assemblies and Passive House certification requiring a high performance building enclosure. The second project is a multi-unit transit-oriented and affordable housing development in the San Francisco Bay Area. This paper will inform designers and builders about building enclosure design considerations and challenges specific to modular construction.
This paper was presented at the 3rd Residential Building Design & Construction Conference in 2016.