BASICS OF VENTILATION
Movement of air through the roof space to remove moisture and heat.
What is roof space ventilation?
Black fungal growth caused by moisture
What is mould?
Vent installed under roof overhangs
What is a soffit vent?
Plastic or membrane layer that slows moisture movement
What is a vapour barrier?
Result of poor ventilation and moisture buildup on surfaces
What is mould growth?
Air entering the roof space through the eaves
What is soffit ventilation?
Frozen moisture forming inside roof spaces
What is frost?
Continuous vent along the roof peak
What is a ridge vent?
Correct side of vapour barrier installation in cold climates
What is the warm side of insulation?
Reduced effectiveness of insulation when wet
What is loss of thermal performance?
Air leaving the roof at the highest point
What is ridge ventilation?
Water forming on cold surfaces from warm air
What is condensation?
Vent installed in a building’s end wall
What is a gable vent?
Process where moisture turns into water inside building cavities
What is condensation?
Air movement path from soffit to ridge
What is continuous roof airflow?
Natural movement of warm air rising through a space.
What is the chimney effect?
Structural damage caused by long-term moisture exposure
What is timber rot or decay?
Single vent installed through roof decking
What is a roof (static) vent?
Sealing building gaps to stop air movement
What is air sealing?
System combining soffit vents, ridge vents, and airflow channels
What is a balanced ventilation system?
Required balance for effective ventilation in a roof system
What is balanced intake and exhaust airflow?
Ice buildup at roof edges that blocks drainage
What is an ice dam?
Component that keeps insulation from blocking airflow
What is a baffle?
Continuous sealed layer preventing moisture entering walls and ceilings
What is a vapour control layer?
Building layer that stops warm moist indoor air entering cold roof spaces
What is a vapour barrier system?