BU685 Insulation of concrete slab-on-ground floors less than 300 M² (July 2023)

This bulletin outlines options for insulating concrete slab-on-ground floors for all housing, and buildings up to 300 m², with a focus on housing. It refers to H1/AS1 5th edition amendment 1, which can be used until 26 November 2026. From 27 November 2026, anyone using H1/AS1 to demonstrate compliance with the Building Code must use the 6th edition.