The short answer
Usually, yes. A typical loft conversion involves new steel beams or timbers bearing into the party wall, cutting in for flashings, and sometimes raising the wall for a dormer — all section 2 works under the Party Wall etc. Act 1996. You will generally need a party structure notice under section 3, served two months before work starts, on each adjoining owner — even if you have planning permission or are using permitted development rights.
Why it matters
The common loft works and why they are notifiable:
- inserting beams or joists into the party wall to carry the new floor;
- cutting into the party wall for flashings and weatherproofing;
- raising, thickening or rebuilding the party wall to form a dormer;
- occasionally, underpinning or strengthening below.
On a mid-terrace house there are usually two party walls, so you may have two or more adjoining owners to serve. Hip-to-gable and L-shaped dormers involve raising or altering existing walls, which (where the wall is shared) remains party structure work under the same notice — not a separate line of junction matter. Planning permission and permitted development are separate regimes — neither removes your duty under the Act.
What to do now
- If your neighbour does dissent, suggest a single agreed surveyor acting fairly for both of you — cheaper and faster than two. Coburns recommends this wherever possible.
- Have your structural drawings ready so the works can be described accurately.
- Identify the party wall(s) and every adjoining owner — both sides on a mid-terrace.
- Serve a party structure notice two months before your planned start.
Common mistakes
- Assuming a loft “inside your own roof” is not notifiable.
- Serving only one neighbour on a mid-terrace.
- Leaving it too late and being caught by the two-month period.
- Overlooking flashing cuts into the neighbour’s wall.
When to call Coburns
Send us your loft drawings and we will confirm exactly which notices are needed, identify all the adjoining owners, and serve the notices for you free of charge.