Does your project need a party wall notice?
Pick what you are building and see at once which party wall notice applies, how much notice you must give, and your next step.
Most party wall pages are organised by legal section, which is no help when you just want to know what your loft or extension needs. This checker works the other way round. Start with your project, and it tells you the section, the notice and the timing.
Whether your project needs a party wall notice depends on what you are building. Section 1 covers building on the boundary, Section 2 covers work to a shared wall such as cutting in steels, and Section 6 covers excavation within 3 to 6 metres of a neighbour. Lofts, extensions and basements usually need a notice. Cosmetic work does not.
Pick your project
The three sections that catch projects
The Party Wall Act has three triggers. Your project may hit one or more of them.
Section 1, line of junction. Building a new wall on or at the boundary between you and your neighbour. One month notice.
Section 2, work to a party structure. Cutting into, raising, underpinning or removing part of a shared wall, which is what most lofts and chimney removals involve. Two months notice.
Section 6, excavation. Digging within 3 metres of a neighbour and below their foundations, or within 6 metres on the 45 degree rule. One month notice. Check this with our excavation distance checker.
A project can trigger more than one. A basement often hits both Section 2 and Section 6. A full width rear extension can hit Section 6 for the foundations and Section 2 if it ties into the party wall. Where two apply, you serve the relevant notices, and the longest period governs your start date.
Notice periods at a glance
The period is the legal minimum between serving the notice and starting work. It is two months for a party structure notice under Section 2, and one month for a line of junction notice under Section 1 or an excavation notice under Section 6. If your project triggers more than one section, plan around the longest period so your build start is realistic. Read the detail in our sections of the Act explained guide.
Why this checker helps
Almost every other site makes you read about Sections 1, 2 and 6 and work out which fits. This flips it. You start with what you are actually doing.
Project first
Pick your loft, extension or basement, not a legal section you do not recognise.
Exact notice
It names the section and the notice period, so you know precisely what to serve.
Honest no
It also tells you when a notice is not needed, so you never serve one you did not have to.
Straight to action
From the result you go to the right next step, with no email gate.
Three situations London homeowners face
These are representative situations, not named clients, but they show how project type sets the notice.
The loft that needed two months
An owner planned a dormer loft with steels cut into the party wall. That is work to a party structure under Section 2, so a two month notice was required. They served early and kept the build on track. The lesson: most lofts touch the party wall, so plan for the two month period.
The basement that hit both
A basement triggered Section 6 for the deep dig and Section 2 for tying into the party wall. Both notices were served, and the longer period set the start date. The lesson: deep projects often need more than one notice, so check early.
The job that needed nothing
An owner replastering and rewiring internally, with no work to the shared wall and no digging, did not need a party wall notice at all. The lesson: cosmetic work usually falls outside the Act, and the checker confirms it so you do not serve needlessly.
Not sure what your project needs?
Tell us what you are building and we will confirm the exact notices and serve them correctly, usually within 24 hours.
Message us on WhatsAppFrequently asked questions
Loft conversions, rear and side extensions, basements, chimney breast removals, underpinning and new boundary walls commonly need a notice. Cosmetic work such as plastering or rewiring usually does not.
Section 1 covers building on the boundary line, Section 2 covers work to an existing party wall or structure such as cutting in steels, and Section 6 covers excavation within 3 to 6 metres of a neighbour. A project can trigger more than one section.
Work to a party structure under Section 2 needs two months notice. A line of junction notice under Section 1 and an excavation notice under Section 6 need one month.
Usually yes. Most loft conversions involve cutting steel beams into the shared party wall, which is work to a party structure under Section 2 and requires two months notice.
Important: This checker gives general guidance based on the project you select and is not legal advice. Whether a notice is required depends on your specific works, the boundary and the proximity to neighbours. A party wall consultant should confirm the exact notices before you serve. Survey of Party Wall can review your drawings and serve the correct notices across London.
