Air Infiltration From Attic Through Ceiling

The two control layers we re concerned about here are.

Air infiltration from attic through ceiling. In a cold un insulated attic heat conducted through the ceiling warms the air near the attic floor. In the day temperatures can get up to 140f in the attic. Consider swapping out or upgrading any duct work that is not insulated properly. Spray foam also reduces infiltration through the ceiling.

This is building science 101. One source is from outdoors through the attic ventilation and the other is from indoors through air leakage across the ceiling plane. Convection is a natural process that can be controlled through the proper application of attic insulation. During the summer standard ceiling insulation reduces the transfer of heat from the attic to the living space.

Spray foam also reduces infiltration through the ceiling. Then there are the control layers meant to control the flow of heat air and moisture across the building envelope. The warm air rises toward the roof where it loses its heat. It reduces energy consumption because the temperature in the attic is lower.

In the day temperatures can get up to 140f in the attic. Additionally the air tightness of the attic construction itself the un intentional air infiltration i e. It reduces energy consumption because the temperature in the attic is lower. Most of the time houses are insulated with materials that do not stop air leakage.

A form of un controlled attic ventilation will also have an influence on the moisture balance. If you have an attic ac unit you should take this opportunity to check the air seals on the duct work.