Reducing attic heat with ventilation

Insulation · Venting Roofs · printed page 239 (PDF page 240)

Book index entries

Attic – Heat – Reducing with Ventilation Helps Reduce Attic Heat Ventilation – Helps Reduce Attic Heat Ventilation Venting Roofs

Text in the illustration

no ventilation
ventilated
100°F
roof rafter
130°F
insulation
ceiling joist
95°F
wall
roof vent
air flow
105°F
80°F
soffit vent
cross section

Generated explanation

Two cross sections compare attic and room temperatures beneath an unventilated roof and a ventilated roof, both with an indicated outdoor temperature of 100°F. Each assembly shows a sloped roof rafter, ceiling joist, attic-floor insulation, and an insulated exterior wall. The unventilated example indicates an attic temperature of 130°F and a room temperature of 95°F. In the ventilated example, arrows show air entering through a soffit vent, passing above the insulation, and exiting through a roof vent; the indicated attic and room temperatures are 105°F and 80°F, respectively.