LRWA Publishes Updated Hot Melt Code of Practice Reflecting BS 6229:2025

To support best practice in flat roofing, the Liquid Roofing and Waterproofing Association (LRWA) has published version 2.2 of its Hot Melt Code of Practice, effective from 14 August 2026.

The updated Code of Practice reflects the recently published BS 6229:2025 and is available free of charge to specifiers, contractors, clients, suppliers and other interested parties.

Developed with technical experts from the UK’s Hot Melt waterproofing industry, the Code provides comprehensive guidance for specifiers and contractors on the selection, design, specification, installation and maintenance of hot-applied polymer-modified bitumen waterproofing systems.

Updated Hot Melt Code of Practice

Hot Melt systems have an established track record of more than 40 years in the UK market. They are recognised for their exceptional waterproofing performance, robustness, long-term durability and suitability for a wide range of roof constructions, from zero falls and inverted warm roofs through to biodiverse and blue roof systems.

The Code covers definitions and terminology, design and installation considerations, health and safety provision, substrate suitability and preparation, structural concrete decks and finishes, application methods, quality control on site, maintenance and training.

This edition supersedes version 2.1, published April 2025. The updated Code of Practice places particular emphasis on achieving correct falls at deck level, since standing water resulting from inadequate falls or drainage can impose additional structural loads, accelerate material deterioration and reduce thermal performance.

Mike Bradbury, LRWA Technical Guidance Manager, said: “This update ensures the LRWA Hot Melt Code of Practice reflects the requirements of BS 6229:2025 and continues to give the industry a definitive, authoritative reference for Hot Melt waterproofing systems. Falls and drainage remain critical to the long-term performance of a roof, and this edition reinforces that guidance throughout.”

The LRWA Hot Melt Code of Practice is intended for continued reference throughout a project, including at the planning stage, when addressing issues identified on-site, and when confirming compliance with recognised best practice. It does not replace manufacturer-specific technical literature or LRWA training and qualifications. It should be read alongside companion documents including the LRWA Car Park Code of Practice and the LRWA Design Guide for Specifiers.

Download the updated LRWA Hot Melt Code of Practice.

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