The short answer
It depends on what the conversion involves. Turning an integral or attached garage into a habitable room is often largely internal — insulating, infilling the garage door opening, a new floor — which may not be notifiable. But where the garage shares a wall with the neighbour (common on semi-detached and terraced houses), or you lower the floor and excavate, or build outwards, the Act can apply under sections 2 and 6. Check before you start.
Why it matters
It is notifiable where you cut into a shared or party wall (inserting a beam, forming new openings, raising the wall), lower the floor slab in a way that needs excavation deeper than the neighbour’s foundations within three metres (section 6), or build a new wall on the boundary. It is usually not notifiable to infill the garage door, add internal insulation and plasterboard, or lay a new internal floor that involves no excavation near the neighbour. The key thing to check is whether the side wall of the garage is actually a party wall on the boundary — many attached garages are built right up to it. Damp-proofing the party wall is also notifiable.
What to do now
- If a surveyor is needed, use one. Both owners can appoint a single impartial ‘agreed surveyor’ rather than one each — quicker, cheaper and less adversarial. Coburns recommends a single agreed surveyor wherever possible.
- Establish whether the garage wall is shared or sits on the boundary.
- Check whether any floor-lowering or excavation is involved, and map the works to sections 2 and 6.
Common mistakes
- Assuming every garage conversion is exempt.
- Missing that the side wall is a party wall.
- Forgetting excavation when lowering the floor.
- Overlooking damp-proofing of the party wall.
When to call Coburns
Send us your plans and we will confirm, free of charge, whether your garage conversion needs a notice — and serve it if so.