The statutory minimums
- Section 1 (line of junction) — at least one month before work starts.
- Section 3 (party structure) — at least two months before work starts.
- Section 6 (adjacent excavation) — at least one month before work starts.
These are minimums, not targets. They run from the date the notice is validly served, and if served by post, you also need to account for deemed service — the Act treats a posted notice as served some days after posting, not on the date you put it in the envelope.
The myth: "the longest period governs the whole project"
Many building owners — and no small number of guides online — assume that if a project needs both a Section 3 notice (two months) and a Section 6 notice (one month), nothing at all can start until the full two months has run on everything. That's not correct.
Notice periods attach to the specific works each notice covers, not to the project as a whole. If your Section 1 or Section 6 works are physically separable from the Section 3 works — for example, excavating a soakaway well away from the shared wall, while party structure work to that wall is covered by a separate, later-starting notice — the Section 1 or 6 works can lawfully proceed at the one-month mark, even while the Section 3 two-month period is still running. What matters is whether the works themselves are genuinely separable on site, not just which notices were served.
Where the works aren't separable — say, excavation immediately beneath the shared wall as part of underpinning it — the practical reality is that you can't start the inseparable elements until every relevant notice period affecting that specific work has run, because starting early would mean carrying out party structure work before its own notice period is complete.
How consent changes the picture
Notice periods exist to give the adjoining owner time to consider and respond. If they consent to a notice in writing, that notice's waiting period effectively becomes irrelevant — you're not waiting out a statutory minimum against an objection that no longer exists. Many building owners with a cooperative neighbour find work starts well inside the "minimum" period because consent was given early.
How an Award changes the picture
If a notice is dissented and the matter goes to a Party Wall Award, the surveyors can set an agreed commencement date for the works — which is often earlier than the individual statutory minimums would otherwise imply, and can align multiple notices to a single start date for practical site management. This is a common and sensible outcome, but it's something the Award provides for, not something the underlying notice periods themselves shorten.
What this means for your notice
If your project needs more than one type of notice, generate them thinking about which works are physically separable and which aren't — that's what determines your real start date, not simply the longest of the individual periods. Where you're unsure whether elements of your project are separable, that's a judgement worth checking with a surveyor before you commit to a programme.