The process of detailing the Net positive house was iterative and took the entire team. Detailing takes a clear understanding of not only the form but, the various layers of the building envelope. The building envelope is highly efficient and focused on creating a continuous seal around the entire house. The mechanical systems in the house allows inflow and outflow of air to the house when windows are not being used. We used raycore SIPs as structure, OSB for sheathing and foil faced Poly ISO for the WRB and continuous insulation. One of the biggest issues we experienced detailing this project was the continuous insulation, the IBC states there must be a continuous layer of insulation around conditioned space. We utilized rafters instead of trusses, allowing us to gain a higher ceiling in the public spaces of the house but presented a detailing problem on the exterior of the house where traditionally a soffit would exist. The transition from wall to roof specifically the insulation, we explored at a 1 to 1 scale in order to fully understand how the materials would interact with each other and lay on the house and came up with a design solution. Another tricky detail we explored was the window R.O, mid way through the design process the decision was made to abandon ZIP board as a WRB, this had serious design implications throughout all the details but the windows had to be redesigned because the nature of the Zip panels provided a structural surface to mount the windows and without ZIP in the new wall system we had to develop a alternate way to mount the windows. Ultimately, after time and iteration we decided to line the window R.O. with ¾ inch plywood to hold the window while screws were permanently driven through the aluminum window frame. This decision was made after consulting Interstate windows because their installation manual states an alternative method of driving the screws through flanges. During the actual construction phase of this project most of our details held their weight and did not have to be modified, as many times construction does not go as planned. However, we did find details that were overlooked or became issues as panels were constructed on site. Overall, Detail this project was successful! These project specific details we investigated will be used as prototype and precedent as the Net Positive studio continues its goal of creating affordable, efficient workforce housing in the future.
The Net Positive Studio 