Pacific Iron and Steel Company, which had developed a formed sheet metal construction for buildings, was given the contract for construction of these buildings in conformance with drawings and specifications prepared by H& N. The design presented a rigid frame structure using columns, roof frame, knees, and sheets pressed into shapes required to withstand wind pressures of 25 pounds per square foot. Multiple punching jigs were to be used to insure interchangeability of connecting parts and to permit erection to be started from any column location. Upon placing orders, it was discovered that the basic manufacturers were not making a standard clad sheet with strength of 525. Accelerated salt spray tests of uncoated 52S specimens showed pitting and oxidation so severe that strength and appearance were seriously impaired. Tests of other clad alloys showed no pitting or loss of section in basic material, The cladding oxidized and sealed cut edges to form a protective coating. Search was made for an alloy with a tensile strength of over 30,000 pounds per square inch and clad to protect the basic material. Reynolds Aluminum Company offered a special sheet which was called 45 clad, Extruded parts such as channels, angles, and clips were made of 615 material, Samples of this 4S clad material were sent to a recognized testing laboratory for testing of strength and resistance to salt spray. Tests for salt spray resistance were made at 100°F for periods up to 250 hours. Results were very satisfactory, and subsequent inspection of structures at Jobsite has verified the durability of the material. The buildings were quite flexibly designed in that they were framed structures with arched ribs four feet on centers, each four-foot module self-supporting against all design loads. This design left a clear space within the building, with 8-foot vertical side walls and no interior supports. Thus buildings 24, feet wide and almost any length could be constructed, Later developments brought combinations of T, L, and parallel-shaped buildings, all capable of being erected on fourfoot modules to any length. In addition, when nested and crated, most of the parts for alumtnum buildings measured approximately forty cubic feet to the weight ton, the optimm relationship for water shipment. Because these buildings were a new product, test erection for structure and weather tightness was required of the manufacturer. Re- sults of tests showed strength of remarkable closeness to design factors, Tests were attended and approved by representatives of H & N, AEC, and J-Division. After the selection of the prefabricated aluminum buildings as a basic building unit and upon receipt of AEC work authorization, the Architectural Department began the task of planning and designing the individual buildings and structures required at each site. Production of necessary drawings for camp facilities, criteria for which were 5-105