Technical Booklet C Site Preparation and Resistance to Contaminants and Moisture·Page 33·6.17
BRE Report BR 262 exposure guidance for cavity walls
BRE Report BR 262 provides guidance on cavity wall exposure to driving rain, including exposure zone maps and maximum recommended exposure zones for various insulated masonry wall types.
BRE Report BR 262 Thermal insulation: avoiding risks provides guidance on exposure of cavity walls to driving rain. It contains a map showing exposure zones and a table giving maximum recommended exposure zones for various insulated masonry walls.
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