1. Survey, design and quotes
A loft specialist or architect surveys the loft, then drawings are produced. Get several quotes for the same design. See is my loft suitable?
2. Permissions
- Planning permission or a lawful development certificate, if needed. See loft planning rules.
- Building Regulations approval, with structural calculations.
- Party wall notices to neighbours, where the work affects a shared wall.
3. Scaffolding and access
Scaffolding usually goes up first. Many loft conversions are built mostly from outside, through the roof, which reduces disruption inside.
4. Structure
New floor joists go in, steel beams are installed, and the roof is altered for a dormer, hip-to-gable or mansard. Building Control will inspect key stages.
5. Windows, roof and weatherproofing
Roof windows or dormer windows are fitted and the roof is made watertight.
6. Stairs and the break-through
The new staircase is fitted, and the opening to the floor below is formed. This is usually the most disruptive stage inside the house.
7. Insulation, first fix and plastering
Insulation goes into the roof and walls, electricians and plumbers run cables and pipes, then walls and ceilings are boarded and plastered.
8. Fire safety
Fire-resisting doors are fitted onto the stairway on each level and interlinked smoke alarms are installed, so there is a protected escape route. See fire doors in homes.
9. Second fix, decorating and sign-off
Sockets, lights, radiators and any en suite are connected, the room is decorated, and scaffolding comes down. Make sure you receive the Building Control completion certificate, electrical certificates and any guarantees.
How long it takes depends on the type of conversion and the size of the job, so ask your specialist for a programme. Compare loft conversion specialists.
Last updated: 14 October 2026
