1. (U,G) Consider a house with inside air temperature of 72 F. Use outdoor air temperature and solar data from the “day-type” WeaTran output from the Dayton International Airport TMY3 file for July 3 1995 at 15 hours (3 pm). The dimensions of the ceiling and flat roof are 30 ft x 50 ft. The house has an attic with a R = 2 (hr-ft2-F/Btu) roof (including convection coefficients on both sides of the roof) with dark shingles (a = 0.9). The ceiling construction is shown below.

5-Roofs_HW

1) (U, G) Find the total thermal resistance R (hr-ft2-F/Btu) and conductance U (Btu/hr-ft2-F), including the thermal resistances caused by convection coefficients on the interior and exterior (winter) surfaces, of the following wall.

4-Walls_HW