Other assemblies
• Below-grade walls
Q = U A (Tground " Ti)
Where Q = heat flow rate
U = U-factor of basement wall (Table 5-8 in the textbook)
A = area of basement wall below grade Tground = ground surface temperature T; = inside air temperature
Tground — Tavg — Amp
Where Tavg = average winter temperature (Table 5-10 in the textbook)
Amp = amplitude of ground temperature variation (Figure 5-7 in the textbook)
• Below-grade floors Q = U A (Tground " Ti)
Where U = U-factor (Table 5-9 in the textbook)
A= basement floor area
• Slab-on-ground construction Q = U’ P (T0 — Ti)
Where U’ = heat transmission loss per linear meter of slab edge (Table 5-11 in the textbook) P = perimeter of slab T0 = outdoor design temperature
Posted in Fundamentals of Heating. Ventilating, and Air-Conditioning