Stack effect

Insulation · The Basics · printed page 234 (PDF page 235)

Original page Sign in to save

Book index entries

Stack Effect Insulation – the Basics

Text in the illustration

A
warm (less dense) air rises
B
additional warm air expands, increasing pressure and pushing household air out through cracks/gaps
C
air leaving the house creates negative pressure in the cooler, lower levels - outdoor air is drawn in through any cracks or gaps
note: assumes calm conditions (no wind)

Generated explanation

A schematic house section illustrates stack-effect airflow under calm, no-wind conditions. A large upward arrow shows warm, less dense air rising from the lower level to the upper level. Red outward arrows at the upper walls and roof depict household air escaping through cracks and gaps as upper-level pressure increases. Light blue inward arrows at the lower walls show outdoor air being drawn in by negative pressure at the cooler, lower levels.

Components

exterior walls pitched roof intermediate floor upper-level ceiling building envelope

Defects shown

air leakage through building-envelope cracks and gaps