Part L Building Regulations: A Guide for Norfolk Homeowners
September 4, 2023by Lee ChambersBuildConstruction0
Part L covers energy performance requirements for building work in England. If you are planning an extension or renovation in Norfolk, establish which requirements apply to your particular work before the specification and price are agreed.
Regulations and guidance are different
The Building Regulations contain the legal requirements. Approved Document L gives guidance on ways to meet them. Different editions and transitional arrangements can apply, so the newest document is not automatically the one governing every project. Ask your designer and building control provider to confirm the applicable standards. See the government’s Approved Document L guidance.
Does renovating part of a house mean upgrading all of it?
No: renovating more than 25% of a building’s surface area does not automatically mean that the entire house must meet all new-build energy standards. Requirements for renovating or replacing thermal elements depend on the type and extent of the work and the applicable regulations. Confirm the required improvements for the affected roof, wall or floor with your designer.
Agree the specification before work starts
- Identify the existing construction and the proposed changes.
- Agree the insulation, windows, doors and relevant services specification.
- Coordinate energy improvements with ventilation, moisture control and the building’s existing fabric.
- Identify the calculations, inspections and completion information required for your project.
For an older or listed property, involve the appropriate conservation adviser early so that energy improvements are compatible with the building.
Plan your Norfolk extension
Our house extension service explains how we approach extending a home. You can also see our South Walsham extension for an example of completed work. Its specification relates to that project and is not a standard design for every property.
Have drawings or an outline of the work? Tell us about your project so we can discuss the next step.
Guidance reviewed September 2026. This article concerns England; requirements elsewhere in the UK differ.
