Technical Booklet F1 Conservation of Fuel and Power in Dwellings·Page 58·Table B1
Cost effective U-value targets for external wall cladding and finish renovation
Sets a target U-value of 0.30 W/m²·K for renewal or application of external wall cladding or rendered finishes, with assessment of technical risk and impact on adjoining buildings.
Solid wall constructions
Renewal of finish or cladding to external wall area or elevation (render or other cladding) or applying a finish or cladding for the first time: 0.30 W/m²·K. External insulation system with rendered finish or cladding to give required U-value. Assess technical risk and impact of increased wall thickness on adjoining buildings. Consider 'breathability' and hygroscopicity of wall construction, ref Part C.
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