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Guidance Note 14 Best practice for the installation of water flow reducing layers in inverted roofs

Publication Year

2026

Document Status

Current

Abstract

Guidance notes on installing water flow reducing layers (WFRL) in inverted warm roofs. Explains its purpose, positioning and installation considerations to improve thermal performance and water management.

Document History

V: 2.2 - 05/05/2026 edition. Supersedes March 2020 edition.

Publisher Information

Liquid Roofing and Waterproofing Association

The Liquid Roofing and Waterproofing Association raises awareness of the technical and financial benefits of liquid applied waterproofing systems and provides independent advice for specifiers.