Conservation of fuel and power in an existing building other than Dwellings

What the new Part L2B applies to

Provision, extension, alteration or renovation of thermal elements, controlled fittings and services.

Extension – including conservatories over 30 sq.m.
Consequential improvements for total floor are >1000sq.m
Material alterations to existing buildings
Material changes of use – when the building is used as a hotel or boarding house

New non-domestic buildings.

Major extensions to existing non-domestic buildings – Greater than 100 sq. m. and 25% of the gross floor area

The requirements for new Dwelling Part L2A.

Reduction in emissions by 25% compared with Part L2 (2002)
A single compliance method – Carbon emission calculation method (CECM)
Limiting heat gains and losses
Providing efficient building services with effective controls
Provide to the owner sufficient information, so that the building can be operated and maintained so as to consume on more fuel and power than is reasonable in the circumstances
More detail on minimum acceptable standards – via second tier documentation
More control of construction quality – Procedures for pressure testing – removal of floor area limit

Part L2B introduces a new concept of Thermal elements.

Definition - A wall, floor or roof that separates the internal conditioned space from the external environment
Thermal elements – there is now a reasonable provision to improve energy efficiency
On provision of new thermal elements (extensions) minimum standards (maximum u values) apply
On replacement of existing thermal elements minimum standards (maximum U values) apply
On retention of existing thermal elements material change of use or material alteration, improvement required above ‘threshold’ U value.
On renovation of existing thermal elements, if more than 25% of surface area is treated

Please note these brief guidance notes are not a substitute for reading the regulations and the Approved Documents (ADs).

For a more authoritative guide you are advised to use the link below to go to the Regulation of Ads.

Multi-residential buildings.

Mixed use buildings.