What This Requirement Covers
Where a garage is attached to or integral within a dwelling, there is a risk of fire spreading from the garage (which may contain vehicles, fuel, and flammable materials) into the habitable areas. Approved Document B requires fire-resisting separation between the garage and the dwelling.
Key Requirements
Integral Garages
- The wall between the garage and the dwelling must achieve at least 30 minutes fire resistance (REI 30)
- The ceiling over the garage (where there is a habitable room above) must achieve at least 30 minutes fire resistance
- Any door between the garage and the dwelling must be FD30 (30 minutes fire resistance) and fitted with a self-closing device
- The door must not open directly into a bedroom
- The garage floor must be at least 100 mm below the level of the adjoining dwelling floor, or the threshold of the connecting door must be raised, to prevent fuel spillage flowing into the dwelling
- There should be no openings (other than the fire door) in the separating wall between the garage and the dwelling
Attached Garages
- Where the garage shares a wall with the dwelling but there is no connecting door, the shared wall must still achieve 30 minutes fire resistance
- Openings in the shared wall are not permitted unless protected by an FD30 door
Detached Garages
- A detached garage more than 1 metre from the boundary requires no specific fire resistance
- A detached garage within 1 metre of the boundary must have the wall facing the boundary constructed to achieve 30 minutes fire resistance with no unprotected areas
Garage as Part of a Flat Block
- Garages within or below a block of flats must be separated from the residential accommodation by compartment walls and floors achieving the same fire resistance as required for the building height
- Vehicle ramps and access routes must not compromise the fire compartmentation of the building
Practical Compliance Tips
- Use fire-rated plasterboard (e.g., 2 layers of 12.5 mm Type F plasterboard) on the garage side of the separating wall for a simple 30-minute solution
- Ensure the FD30 door between the garage and the house has an effective self-closing device and is not propped open
- Check that any service penetrations through the garage/dwelling wall are properly fire-stopped
- The 100 mm step-down at the garage floor is commonly missed during construction; verify this at foundation stage
- Roof voids above garages must not communicate with roof voids above the dwelling unless a cavity barrier is provided
- Do not install a cat flap, letter plate, or any other opening in the garage/dwelling fire door