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Address & Contact details:
Ravago Building Solutions

Estuary Road
Kings Lynn
PE30 2HJ
Tel +44 (0) 7790 542312 Overview
Full details of RIBA approved CPD materials offered by Ravago Building Solutions are available to auto-generate as PDF and include company contact information: Overview for Ravago Building Solutions

Ravago Building Solutions


Ravago Building Solutions is the largest producer of extruded polystyrene (XPS) insulation in Europe, following its acquisition in 2018 of seven XPS production plants and the technology from DowDuPontInc. It's market leading Ravatherm XPS X thermal insulation boards can be used in a range of roofing and flooring applications.

CPD Material (1)

This CPD article will discuss the Water Flow Reducing Layer as central to the thermal performance of an inverted flat roof - minimising heat loss due to the rainwater cooling effect. It explains the crucial role they play and how to properly account for their presence in U-value calculations. By the end of the CPD you should have a greater understanding of:
- Core principles of an inverted roof
- The difference between declared lambda and design lambda
- The role that a Water Flow Reducing Layer (WFRL) plays in an inverted roof
- How to perform a more accurate U-value calculation for an inverted roof taking into account moisture conversion factor
Knowledge level:
Material type: Article


Ravago Building Solutions has CPD Materials in the following areas: -

RIBA Core Curriculum areas