Lampeter

This flat roof in west Wales needed proper ventilation to resolve moisture build up, a common problem for cold roofs (explained here in relation to warm roofing) especially in such notoriously rainy areas of the UK.

Cold roofs are not really "cold". In cold roofing, as can be seen in the photos, insulation is laid between joists with space left for ventilation, which allows moist air to escape rather than forming condensation and…