747 Wing House
The 747 Wing House was built on the site where existing Duquette structures had burned. Some of the materials from the previous building were used as walkways. The use of the existing pad minimized site grading. The foundation used many of the existing concrete retaining walls but they were rebuilt and reinforced as required to meet new code regulations. This greatly reduced the amount of concrete needed to make the foundation and new walls. Because the wings are only supported in four primary places to the ground, the foundation was further minimized. Both main wings are held up entirely by the four large mounts that the engines originally hung from. By designing the weight distribution on the mounts, it allowed for the outside walls of the building to be made of high efficiency self-supporting glass instead of conventional load-bearing wooden walls. This maximizes solar gain for heating and allows the entire building to be opened to the outside. This also keeps it cool in the summers and minimizes the need for artificial light.
Shallow foundation
The disadvantages are the lack of access from below for utility lines, the potential for large heat losses where ground temperatures fall significantly below the interior temperature, and a very low elevation that exposes the building to flood damage in even moderate rains. Remodeling or extending such a structure may also be more difficult. Over the long term, ground settling (or subsidence) may be a problem, as a slab foundation cannot be readily jacked up to compensate; proper soil compaction prior to pour can minimize this. The slab can be decoupled from ground temperatures by insulation, with the concrete poured directly over insulation (for example, extruded polystyrene foam panels), or heating provisions (such as hydronic heating) can be built into the slab.