A protected stair
The stair from the loft to the final exit must be enclosed in fire-resisting construction. Open-plan lower floors usually need to be reworked or fitted with a sprinkler/mist system.
Fire doors
Habitable rooms opening onto the protected stair generally need 30-minute fire doors with smoke seals and self-closers. Glazing in those routes needs to be fire-rated.
Alarms and escape
Mains-wired interlinked smoke alarms throughout, and openable escape windows from the loft sized to the standard. A small detail wrong here often delays the Completion Certificate.
Frequently asked
Sometimes — with a sprinkler or mist system, or by re-enclosing the stair. Take advice before you commit.