Underside Of Roof Damp

When this warm moist air hits the cold air in the roof space water droplets condense on the nearest cold surface the roofing felt.

Underside of roof damp. Ponce technical specialist with professional roof consultants. When humid air from the interior makes contact with the underside of the roof surface the water vapor it s carrying turns into liquid water explains jose f. The cause depends on whether you have an unconditioned attic or a conditioned attic. The source of the attic moisture is usually indoor air that enters the attic through ceiling cracks.

If attic air is humid and roof sheathing is cold condensation or frost can accumulate on the underside of the sheathing. Such cookers often allow for the quick rise of moist air leaving behind the cold air. Another leading cause of condensation in roofs is the use of wood burner cookers. Picture a cloud of moisture floating overhead between the rafters.

The same phenomenon happens with roof systems. In the event of the attic not being properly ventilated this would condense on the underside of the roof. Condensation will arise as a result of warm moist air penetrating up through the ceiling. Think of a cold drink sitting out on a summer day.

Warm moist air enters the roof space through gaps in loft hatches or where bathroom plumbing or other services go through the roof space. This leads to the formation of damp spots on the surface of the roof. Warm air can contain more moisture than colder air. When this warm air reaches the spaces in the roofs it gets in contact with cold air and condenses.

As it cools it can t hold as much moisture.