Do I Need a Party Wall Notice? Find Out in 2 Minutes
Planning a loft conversion, rear extension, or basement dig in London? The first question your builder, architect, and solicitor will all ask is the same one: have you served your party wall notice? Most homeowners have no idea whether they need one or which type. The Party Wall etc. Act 1996 covers three separate situations under Sections 1, 2, and 6. Each one triggers a different notice, a different timeline, and different obligations for you and your neighbour. Use this free checker to get a clear answer based on your specific project. No jargon. No sign-up. Takes under two minutes.
How to Use This Checker
You do not need any legal knowledge. Here is how it works:
Step 1 — Answer each question honestly based on what you are actually planning to build.
Step 2 — Read the hint text under each question — it explains the legal trigger in plain English.
Step 3 — Get your result — which section of the Act applies, which notice you need, and your deadline.
Step 4 — Use the WhatsApp link at the end to get a free personalised Notice Roadmap for your postcode and project within one business day.
Which Section of the Party Wall Act Applies to Your Project?
The Party Wall etc. Act 1996 is not one single rule. It works through three distinct sections, and your project may trigger one, two, or all three depending on what you are building and where.
Section 1 New Wall on the Boundary Line Applies when you build a new wall on or astride the line of junction — the legal boundary between your property and your neighbour’s land. ⏱ 1 month notice required
Section 2 Works to an Existing Party Wall Covers loft conversions, rear extensions, steel beam insertions, and any structural alteration to a wall shared between two properties. ⏱ 2 months notice required
Section 6 Excavation Near a Neighbour Applies to basement digs and deep excavations within 3 or 6 metres of a neighbouring structure, depending on your excavation depth. ⏱ 1 month notice required
Section 1 — Building a New Wall on the Boundary
Section 1 of the Party Wall etc. Act 1996 applies when you intend to build a new wall directly on the line of junction between your property and your neighbour’s. You must serve a Line of Junction Notice at least one month before work starts.
Your neighbour has two options. They can consent to the wall sitting on the shared boundary — in which case both owners share rights and responsibilities under the Act. Or they can require the wall to be built entirely on your side. If they do not respond within 14 days, the wall must be built within your own land.
This section applies regularly on new-build side extensions and infill projects across London where the proposed wall runs along a shared garden or courtyard boundary.
Section 2 — Works to an Existing Party Wall
Section 2 is the most commonly triggered section of the Act in London. It covers any structural work to a wall that sits on the boundary between two properties. Notice must be served at least two months before work begins.
This includes cutting into the party wall to install steel beams, raising or lowering the wall, removing chimney breasts, and inserting damp-proof courses. Loft conversions in terraced and semi-detached houses almost always trigger Section 2, as do most rear extensions involving work to the shared flank wall.
If your neighbour does not respond within 14 days, a dispute is legally deemed to have arisen. Both sides must then appoint a party wall surveyor — either an agreed surveyor acting for both, or separate surveyors who appoint a third if needed.
Section 6 — Excavation Near a Neighbouring Structure
Section 6 applies to basement digs, underpinning, and deep excavations. If your proposed excavation falls within three metres of a neighbouring building and goes deeper than their foundations, you must serve written notice at least one month before breaking ground.
A second trigger applies within six metres: if a line drawn downward at 45 degrees from the base of the neighbouring foundations is cut by your proposed excavation, notice is required. This is called the 45-degree rule. A surveyor can confirm whether the rule is triggered in a single site visit.
A Schedule of Condition — a full photographic and written record of the neighbouring property’s condition before works begin — is strongly recommended before any excavation starts. Without it, attributing responsibility for any cracking or settlement becomes very difficult for both sides.
What Happens After You Serve Notice?
Once notice is served, your neighbour has 14 days to respond in writing. They can consent — in which case works may proceed after the notice period expires — or they can dissent, which triggers the appointment of a party wall surveyor and the preparation of a Party Wall Award.
The Party Wall Award is a legally binding document. It sets out how works will be carried out, the permitted working hours, access arrangements, and the process for assessing and remedying any damage. Both the building owner and the adjoining owner are bound by it.
If you start works without serving notice, your neighbour can apply to the court for an injunction to stop the build. The cost of defending that application falls on you. Serving notice is always cheaper.
o You Always Need a Party Wall Surveyor?
Not always. If your neighbour consents in writing to your works under Section 2, you do not legally need a surveyor to draw up an Award. Works can begin once the notice period expires and written consent is confirmed.
That said, a Schedule of Condition is worth commissioning even with consent. It creates a before-and-after record that protects both you and your neighbour if any dispute about damage arises later. Most experienced London surveyors and solicitors recommend one as standard practice.
For basement excavations under Section 6, a Schedule of Condition is not optional — it is essential. Settlement and cracking from excavation can appear weeks or months after work is complete.
Party Wall Notice — Frequently Asked Questions
These are the questions London homeowners ask us most often. Every answer is based on the Party Wall Act 1996 as it applies in England and Wales.
Q1: How much notice do I need to give my neighbour?
A1: It depends on which section is triggered. Under Section 2 works to an existing party wall you must give at least two months’ written notice before work begins. Under Section 1 (new boundary wall) and Section 6 (excavation), the notice period is one month. Notice periods cannot be waived, even with verbal agreement. The clock starts from the date the notice is received, not the date it is sent.
Q2: What if my neighbour ignores the party wall notice?
A2: If your neighbour does not respond within 14 days of receiving the notice, a dispute is legally deemed to have arisen under the Party Wall etc. Act 1996. You cannot start works. A party wall surveyor must be appointed and a Party Wall Award prepared before work can begin.
Q3: Can I do a loft conversion without a party wall notice?
A3: In a terraced or semi-detached property, almost certainly not. A loft conversion typically involves cutting into or raising the party wall to install structural steels, which triggers Section 2 of the Act. You must serve notice at least two months before work begins. Starting without notice leaves you legally exposed your neighbour can apply for an injunction and the legal costs fall on you.
Q4: How much does a party wall surveyor cost in London?
A4: Party wall surveyor fees in London typically range from £750 to £2,500 for a straightforward instruction covering one adjoining owner notice, award, and Schedule of Condition included. More complex projects with multiple adjoining owners, basement excavations, or significant structural works will sit higher. The building owner pays the fees in most cases. Ask us for a fixed-fee quote upfront.
Q5: Does the Party Wall Act apply to detached houses?
A5: Yes in some cases. A detached house with no shared walls will not trigger Section 2. But if you are building a new wall on the boundary (Section 1) or excavating within 3 or 6 metres of a neighbouring structure (Section 6), the Act still applies. Basement projects on detached London properties regularly trigger Section 6 because excavation depth often exceeds neighbouring foundations.
Q6: What is a Party Wall Award?
A6:A Party Wall Award — also called a party wall agreement is a legally binding document prepared by a party wall surveyor. It sets out the rights and obligations of both the building owner and the adjoining owner during and after the works. It specifies how works will be carried out, permitted working hours, access rights, and the damage assessment process. It is required when a neighbour dissents or fails to respond to notice.
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