Specify which statement is true () and which false (X) a) Softwood has stronger properties than hardwood b) Nominal dimensions are used to specify lumber sizes c) The actual dimensions of lumber is usually larger than the nominal dimensions. d) Joists are usually supported on Beams and Beams usually supported on Posts e) Studs are used horizontally in walls f) Surfaced lumber is the same as dressed lumber

Awall of 0.5m thickness is to be constructed from a material which has average thermal conductivity of 1.4 w/mk. the wall is to be insulated with a material having an average thermal conductivity of 0.35 w/mk so that heat loss per square meter shall not exceed 1450 w. assume inner wall surface temperature of 1200°c and outer surface temperature of the insulation to be 15°c. calculate the thickness of insulation required.