Abstract: Foldable building units are provided based on structural frame and connection assembly designs that enable greater construction efficiency and flexibility. The structural frame and connection assembly designs allow for easier connection of frame elements in the prefabrication process of the foldable building units and for easier connection of frame elements at the building site, for example, of foldably connected frame elements after unfolding. They also allow for more finish in the prefabrication process, and/or less and faster work at the building site, for example, by enabling conventional structural lumber grids that can be continuous through the edges and corners of the building envelope for conventional exterior finishing, while providing a tight building envelope with reduced heat transfer, particularly, through the edges of the foldable building unit.

Abstract: Foldable building units are provided based on structural frame and connection assembly designs that enable greater construction efficiency and flexibility. The structural frame and connection assembly designs allow for easier connection of frame elements in the prefabrication process of the foldable building units and for easier connection of frame elements at the building site, for example, of foldably connected frame elements after unfolding. They also allow for more finish in the pre-fabrication process, and/or less and faster work at the building site, for example, by enabling conventional structural lumber grids that can be continuous through the edges and corners of the building envelope for conventional exterior finishing, while providing a tight building envelope with reduced heat transfer, particularly, through the edges of the foldable building unit.