Date issued: 6 May 2022
In April 2022, an updated version of the Building Regulations Approved Document L series was released. Previously these were separated into L1A(1), L1B(2), L2A(3) and L2B(4), but now there are just two: Volume 1: Dwellings(5) and Volume 2: Buildings other than dwellings(6). These approved documents cover England only. The new Building Regulations Approved Document L Volume 1 and Volume 2 came into effect on 15 June 2022. This ISU covers Volume 1: Dwellings.
Legislation, normative references and current standards have been updated throughout where necessary.
There are two main changes in the new approved document with regard to heating systems. The first involves the insulation of heating and hot water pipework. The most significant change is that Section 4.24 of the new document states that when a boiler or hot water storage vessel is replaced in any existing system, any accessible pipework in the dwelling should be insulated. Table 4.4 gives the minimum thickness of insulation required, which depend on the pipe diameter.
The second change involves the sizing of a new heating system. Section 5.10 states that when a wet heating system is either newly installed or fully replaced in an existing building, all parts of the system, including pipework and radiators, should be sized to allow the space heating system to operate at a maximum flow temperature of 55°C or lower. To help achieve this, an appropriate heat loss calculation for the dwelling will need to be carried out.
Previously it was merely good practice to fit thermostatic radiator valves (TRV) to existing radiators that did not have thermostatic control when replacing a boiler; now Section 5.20 makes this a requirement.
- Building Regulations Approved Document L1A: Conservation of fuel and power in new dwellings
- Building Regulations Approved Document L1B: Conservation of fuel and power in existing dwellings
- Building Regulations Approved Document L2A: Conservation of fuel and power in new buildings other than dwellings
- Building Regulations Approved Document L1A: Conservation of fuel and power in existing buildings other than dwellings
- Building Regulations Approved Document L Volume 1: Dwellings
- Building Regulations Approved Document L Volume 2: Buildings other than dwellings.
(This article previously appeared in Registered Gas Engineer’s July 2022 issue)