Loft conversions and party walls
Almost every loft conversion in a terraced or semi-detached house involves the party wall. Steel beams, a raised gable or a chimney breast removal all need notice under the Party Wall etc. Act 1996, and the notice period is two months.
Which parts of a loft conversion are notifiable?
Most of it falls under section 2 of the Act, which covers work to an existing party wall. Typical items are:
- Steel beams bearing on the party wall. Cutting pockets into the wall for new floor or roof beams, usually with padstones underneath.
- Raising the party wall. Common with hip-to-gable conversions on semi-detached houses, and with mansard or rear dormer conversions on terraces, where the wall is built up to the new roof line.
- Removing chimney breasts in the loft or on the floors below, to make room for the stairs. See our chimney breast guide.
- Exposing the party wall. Even uncovering it is notifiable. Under section 2(2)(n), stripping the roof back for a dormer or hip-to-gable conversion exposes a party wall that was previously enclosed, and it must be given adequate weathering while it's open.
- Cutting in flashings where the new roof meets the neighbour's wall or roof.
- Rebuilding a defective or missing loft-level party wall, which is common in older terraces. See what your party wall is likely to be made of.
The notice must be served at least two months before this work starts, on each adjoining owner. A mid-terrace house usually has two.
Plan it early. If your neighbour dissents, an award has to be agreed before the work affecting the party wall can start. Serving notices as soon as your structural drawings are ready keeps the loft programme on track.
What the award usually covers
- The structural engineer's drawings and calculations for the beams and padstones
- How deep beam pockets may go into a solid wall (generally no more than about halfway), or confirmation that work stays within your leaf of a cavity wall
- Protection of the neighbour's loft and belongings during the work, including temporary weathering of the exposed party wall and roof, and making good any disturbance
- Working hours, and how dust and noise from cutting into the wall are controlled
- Scaffolding and access arrangements where the work needs them
- A schedule of condition of the neighbour's property, especially their top-floor ceilings and the party wall
Typical timeline
- Drawings ready: structural drawings are needed to describe the work properly.
- Notices served: two months before the party wall work starts.
- 14 days: your neighbours respond, either consenting or dissenting.
- If they dissent: the surveyors agree the award and record the condition of the neighbour's home. This can often be done within the notice period.
- Work starts in line with the award.
Costs
Notices are £100 per neighbour, covering all the notices they need. If a neighbour dissents, an award starts from £995, and a schedule of condition from £390. As the building owner you normally pay the surveyors' fees, including those of your neighbour's surveyor. See full pricing.
Loft conversion questions
Do I need a party wall notice for a Velux loft conversion?
If the conversion puts new beams or joists into the party wall, or involves any other work to it, yes. A rooflight-only conversion that bears entirely on your own structure, without touching the party wall, may not need one. Most do involve the party wall, though, so it's worth checking.
Can my neighbour stop my loft conversion?
No. The Act doesn't give neighbours a veto over work you're entitled to do. It makes sure the work is done in a way that protects their property, through an award if they dissent.
Does permitted development mean I don't need a party wall notice?
No. Planning permission, permitted development and building regulations are all separate from the Party Wall Act. You may need any or all of them.
Not sure if the Act applies to your project?
Tell us what you're planning. We'll tell you, free of charge, whether you need to serve notice and what happens next.