Loft condensation caused by blocked ventilation
Why it happens here
Victorian and Edwardian roofs in Wellington rely on airflow through eaves and gaps between tiles. Foam sprayed between rafters seals those paths, so warm moist air from the house condenses on cold timbers. The town's damp climate makes it worse.
Our approach
We remove the foam, clear the ventilation paths and check the eaves are open. Where ventilation cannot be restored externally, we plan an internal route. A thermal imaging camera pass confirms the roof is drying out.