Technical Booklet K Ventilation·Page 14·1.5
Building Air Permeability and Airtightness
More airtight buildings are anticipated due to energy efficiency and carbon reduction drivers, with achievable air permeability targets of 2-4 m³/(h.m²) of envelope area at 50 Pa pressure difference through good design and construction.
It can be anticipated that there will be a continual trend towards more airtight buildings due to drivers for higher energy efficiency and lower carbon emissions. Through good design and construction, buildings can achieve an air permeability down to around 2 – 4 m3/(h.m2) of envelope area at 50 Pascal (Pa) pressure difference.
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