For most skillion roofs the amount of air movement in the roof cavity, although limited, is sufficient to remove small amounts of vapour. The trick is to keep those amounts of water vapour small.
Showing results 1-4 of 4
BRANZ has been measuring moisture levels in a school’s classrooms. This information is providing a sound basis for understanding the indoor climate and designing moisture-safe long-span roofs in schools.
BRANZ physicists have developed a useful calculation for designers to work out the minimum number and area of vents required in roof spaces.
As we push for higher performance from our houses, expectations for airtightness and ventilation are changing rapidly. Some changes will be needed in design to improve airtightness, and mechanical ventilation is likely to soon be the norm.