Part L1A Approved Document

We inspect and test homes for uncontrolled air flows, meeting the requirements for the approved document for 'Conservation of fuel and power in new dwellings'

Meeting the building regulation
requirements For Part L1A.

As from 6th April 2006 Approved Document L1A came into effect.

You can view these new regulations by downloading this pdf (Requires Adobe Acrobat Reader).

Does every dwelling need to be tested?

For dwelling’s (L1A), air leakage testing is mandatory for a percentage of each building type. Air leakage should not exceed 10m³/hr/m² of the building envelope.

Number of instances of the dwelling type	Number of tests to be carried out on each dwelling type
4 or less	One test of each dwelling type
Greater than 4, but equal or less than 40	Two tests of each dwelling type
More than 40	At least 5% of the dwelling type, unless the first 5 units of the type that are Tested achieve the design air permeability, when the sampling frequency can be subsequently reduced to 2%