CHAPTER 5,10 PERSONNEL BUILDINGS One of the major expenditures in developing camp facilities was to be for housing. Therefore, extensive investigations were made of various kinds of buildings, both those which could be domestically prefabricated to a maximum extent and those which could be built at the Jobsite. These included concrete, concrete block, brick, frame with stucco, plywood, steel, aluminum, and various combinations of these materials, Careful cost analyses were made of all types, and it was found that prefabricated metal buildings were most advantageous both as to adaptability and final cost. It then became necessary to find some metal or combination of metals which could be prefabricated in modules of 3 or 4 feet and which would offer sufficient resistance to the elements of high humidity, high temperature, and constant salt spray. Steel, the most conventional building metal, could not be used because, even with very frequent painting, it could not last the five years required by design criteria. It had been observed that scrap sections of airplane wings and fuselages that had been lying in the surf on the reef for more than five years (since wartime operations on the Atoll) were still bright, shiny, and basically sound. The only corrosion was on aluminum castings, the alloy used for castings being particularly susceptible. Investigation disclosed that the aluminum sheets were a clad aluminum alloy, and it was reasoned that this would be an ideal material for the skin of buildings that would be subjected to the continuous spindrift carried across the islands from the breakers by the constant trade winds. An additional advantage was the good heat insulation quality of the alloy. It was learned from aluminum manufacturers that they had a sheet aluminum that would develop the structural characteristics required as well as a corrosion resistance equal to that of the airplane wings. Preliminary designs were then made by the Engineering Division of H & N, and determination was reached that a structure 24 feet wide, clear span, with vertical walls, would be most adaptable and useful for the structures to be built. Structural analysis showed that if an aluminum alloy could be obtained with a tensile strength corresponding to the 525 structural designation, yet clad with pure aluminum, a practical rigid frame structure could be fabricated to meet the design requirements. Based upon these design criteria prepared by H & N, bids were requested from manufacturers of prefabricated structures for a 24-foot clear span structure with a double roof, two-thirds of side walls vented, and an 8-foot eave line, all parts to be of a clad aluminum equal in strength and corrosion resistance to 528. 5-104