Key Learning outcomes
- Core principles of an inverted roof
- Difference between declared lambda and design lambda
- How to calculate the moisture conversion factor
- Value of assurance schemes
The Water Flow Reducing Layer is central to the thermal performance of an inverted flat roof, minimising heat loss due to the rainwater cooling effect. When designing an inverted roof it is essential to understand their crucial role and how to properly account for their presence in U-value calculations.
Portions of this article first appeared in RIBAJ. Copyright 2020 Ravago Building Solutions.