A method of constructing a building is disclosed, including selecting a standard dimension less than a wide-load trucking permit limit and designing a building on a grid defined by the selected standard dimension. The building includes a plurality of prefabricated elements, wherein each prefabricated element has a width correspond to the selected standard dimension. The plurality of prefabricated elements includes a wall panel, a roof panel, a laterally resistive frame, and a rebar cage. The method includes fabricating each of the plurality of prefabricated elements at a manufacturing plant and transporting the elements by truck to a building site. The method includes constructing intersecting grade beam footings at the building site and pouring a slab between the intersecting grade beam footings. The grade beam footings include the rebar cage and have a uniform width and depth, the grade beam footings and the slab having contiguous upper surfaces.