A common brick wall, 20cm thick, is finished on the inside with 2.5cm of cement concrete. Calculate the total thermal resistance of the wall and the heat transfer rate per m2 if the overall temperature difference is 40 K.

1. Calculate the overall heat-transfer coefficient (U=?) for a frame construction wall made of brick veneer (120-lbm/ft³) with 3-in. fiberglass insulation bats between the 2x4 wood studs (softwood) that are 16-in. on center. The wind velocity is 15-mph. Fill out the table below also utilizing materials data from the textbook. Also, calculate the total heat loss if the referenced wall was 9-ft tall and 35-ft in length set in Ohio, Clevland @ 99% winter OAT with an indoor setpoint of 75°F. Hint: 2x4 wood studs are 16-in. on center and 2-in. thick by 4-in. deep thus the empty space between each stud is 14-in. Remember use R = L/K & R = 1/C for materials. Between Frame (R-Value) At Framing (R-Value) Outside Surface 4-in. Face Brick (k=middle value) 1/2-in. Sheathing reg. density 3-in. Insulation Batt 2"x4" Wood Studs (k=middle value) 1/2-in. Gypsum Board Inside Surface Total (R-Value): ● U = ● Q= Btu/(hr-ft²-F) Btu/h Heat Loss

100 mm 50 mm 100 mm Tin T out Figure 3 illustrates a compound wall constructed of an inner and outer layer of standard brick and a central layer of standard cavity wall insulation material. If the temperature inside is 21°C and the temperature outside -3°C, what is the rate of heat transfer through the wall per unit area? Data: take the value of the convective heat transfer coefficient for both inside and outside in (c) as 10 Wm?K