The short answer
For a typical loft conversion, allow around one to two months of party wall lead time before work to the party wall can start. The main driver is the two-month party structure notice period (section 3), because most lofts cut new steel beams into the shared wall. If your neighbour consents, the process is simpler; if they dissent, add time for the surveyor (or surveyors) to agree the award. The single most useful thing you can do is serve notice early — ideally as soon as you have your structural design.
Why it matters
A loft conversion timeline usually runs like this:
- Day 0 — serve the notice. A party structure notice (section 3) must give at least two months before the party-wall work begins.
- Within 14 days — the neighbour responds. They consent, or they dissent (or stay silent, which counts as a dispute).
- If they consent — no award is needed, though you normally still wait until the two-month period expires before starting, unless they agree in writing to an earlier start.
- If a dispute arises — a surveyor prepares a schedule of condition and the award. With a single agreed surveyor this is quicker; with one surveyor each it takes longer.
Realistically: consent tends to mean about two months (the notice period); a dispute settled by an agreed surveyor often resolves within roughly six to ten weeks; two surveyors going back and forth takes longer. Crucially, that two-month period runs alongside your planning, building regulations and builder lead time — so if you serve early, it often isn’t the critical path at all.
What to do now
- Get your structural design first, so the notice describes the works accurately.
- Serve the party structure notice as early as you can, and line the two months up against your build programme.
- Where a surveyor is needed, a single agreed surveyor for both owners is quicker and cheaper than two — the route Coburns recommends.
- If a dispute does arise, agreeing the straightforward points directly keeps the award — and the timeline — tight.
Common mistakes
- Serving the notice too late and holding up the build.
- Assuming consent lets you start immediately — the notice period still applies unless waived in writing.
- Forgetting the second neighbour on a mid-terrace.
- Assuming a dissent stops the project — it only adds the award step.
When to call Coburns
Send us your structural drawings and we will serve the right notices promptly and keep your loft conversion timeline as tight as the Act allows.