Abstract: A roof assembly for a transportable building construction includes a plurality of ceiling joists and at least one roof unit rotatably secured to at least one ceiling joist, the at least one roof unit formed from a plurality of rafters wherein the at least one roof unit is moveable between a collapsed position whereby the plurality the plurality of rafters of the at least one roof unit lie in a plane substantially parallel to the plurality of ceiling joists, and an assembled position whereby each of the plurality of rafters of the at least one roof unit extends entirely to an apex of the at least one roof unit.