Building regulations
Building regulations drawings
Building regulations are the rules for how a loft or an extension is built. They cover structure, fire escape, insulation and ventilation. A loft also looks at the new stair. An extension also looks at the new walls, the roof and the opening back into the house. The drawings show a building control body how the agreed work is to be built. This approval is separate from planning permission.
Lofts and extensions
A loft that becomes a room normally needs building regulations approval even when the planning route was permitted development. The set covers the stair from the floor below, the escape route, the insulation of the roof and the new floor. More on the room itself is on the loft conversion page. The Planning Portal explains the loft case.
Most extensions also need building regulations approval, including a single-storey rear extension that was permitted development. The set covers the new walls and roof, the insulation, the junction with the existing house, and any beam over the opening into the room behind. Drainage is included where the extension changes it. More on the types of extension is on the home extensions page. The Planning Portal explains the extension case.
What a technical pack usually includes
- Plans and elevations coordinated with the agreed design.
- A section through the new loft, or through the extension and its junction with the house.
- Construction information for the loft floor, stair and roof, or for the extension walls, roof and opening.
- Notes for the builder covering the parts of the project that have been drawn.
What building control usually asks for
Once the design is agreed, the building regulations set is prepared for that design and sent to a building control body. The body checks the proposal and inspects the work on site. The drawings are the information for that check. Approval is the building control body’s decision. Party wall matters and specialist surveys sit outside those drawings.
Government guidance on when this approval is needed is on GOV.UK. The building regulations set can follow planning drawings that already exist, including drawings prepared by someone else.
Planning, building regulations and calculations
Planning permission, permitted development and a Lawful Development Certificate answer a planning question. Building regulations answer how the work is built. The steel is a third piece of work.
- Planning applications and the permitted development and certificate route deal with the planning position. A longer note is in planning permission and building regulations.
- These drawings are the building regulations set for the agreed loft or extension.
- Structural calculations size the beams and roof of an extension, and the new floor and roof members of a loft. They normally accompany this stage, and they are separate from the planning drawings.
Common questions
I already have planning permission. Do I still need these drawings?
Usually, yes, before a loft becomes a room or an extension is built. Planning permission and building regulations approval are different. The Planning Portal explains this for a loft and for an extension.
Are building regulations drawings the same as the planning drawings?
They are a later set. Planning drawings show the proposal. Building regulations drawings show how that agreed design is built.
Does a drawing mean the work has been approved?
A drawing describes the proposal. Approval is decided by the building control body, and by the local authority where planning permission is required.
Can these drawings follow plans that already exist?
Yes. The building regulations set can be prepared from the address, the planning drawings and a short note of what is going to be built.