Fire safety in houses is covered by Part B of the Building Regulations, with practical guidance in Approved Document B Volume 1 (Dwellings). Building control will check the escape strategy for a loft conversion before signing it off, so it needs to be designed in from the start.
Escape routes
| Situation | Typical provision |
|---|---|
| Floor not more than 4.5 m above ground level (for example, a loft room over a bungalow) | Each habitable room has an escape window, or opens directly onto a hall or stair leading to a final exit |
| New floor more than 4.5 m above ground level (for example, a third storey added to a two-storey house) | A protected stairway from the top floor to a final exit, with fire-resisting doors to the habitable rooms that open onto it, or an alternative escape route |
Escape windows
Where an escape window is relied on, the openable part should give an unobstructed area of at least 0.33 m², be at least 450 mm high and 450 mm wide, and have its bottom no more than 1100 mm above the floor. It must lead to a place free from danger. Escape rooflights must meet the same requirements and be positioned so that someone can get out and be reached by rescue.
Protected stairways and fire doors
A protected stairway is enclosed by fire-resisting construction, usually providing 30 minutes, with fire-resisting doors (minimum E20) to the habitable rooms. Glazing in the enclosure must be fire-resisting. Open-plan ground floors that would break the protected route need an alternative, such as a fire-separated route or sprinkler protection, agreed with building control.
Fire separation and alarms
- The new floor normally needs at least 30 minutes' fire resistance, which may mean upgrading the existing ceiling below.
- Smoke alarms should be mains-powered with a standby supply and interlinked, in the circulation spaces on every storey (BS 5839-6, Grade D, minimum category LD3).
- A heat alarm is needed in a kitchen that opens onto the escape route without a door.
- Hold the electrical certificate for the alarm circuit with your building control completion certificate.
We record the agreed escape strategy, fire doors and alarm positions in the fire safety section of our handover pack.