Avoid Delays: Party Wall Section 6 Steps for England and Wales Owners
Section 6 of the Party Wall etc. Act 1996 applies when you plan to excavate within 3 metres of a neighbouring building and dig below its foundations, or within 6 metres if the work crosses a 45 degree line drawn from the base of that foundation. If either test is met, you must prepare drawings showing the depth and location of the work and serve one month’s notice before starting, or instruct a party wall surveyor to handle it for you.
TL;DR:
Excavation within 3 meters that goes below the neighbour’s foundation or within 6 meters crossing a 45 degree line triggers section 6, requiring detailed notice and drawings.
Accurate information on the neighbour’s foundation depth and precise plotting of the 45 degree plane are essential to determine if section 6 applies, often involving trial pits or existing records.
Notice serving must be at least one month before work, including scaled plans, cross-sections, and details of underpinning or safeguards, with incomplete notices risking invalidation.
Response periods are limited to 14 days, with silence deemed dissent, and unresolved disputes are managed through appointed surveyors and binding awards under section 10.
Proper pre-work surveys, detailed method statements, and clear contractual access rights reduce delays, disputes, and costs during excavation projects near party walls.
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Table of Contents
The legal triggers: how to apply the 3 metre and 6 metre plus 45 degree tests
What to include in a section 6 notice and how to prepare the mandatory drawings
Timings, responses and deemed dissent: practical implications for your programme
If there’s a dispute: appointing surveyors and the party wall award process
Duties and liabilities: underpinning, making good and technical safeguards
Practical steps before you start: gathering technical evidence and instructing surveyors
Completion, records and what to do if the notice has expired
Practitioner perspective: common pitfalls and how professional surveying prevents delay
How Altura Surveyors can help with your section 6 requirements
The legal triggers: how to apply the 3 metre and 6 metre plus 45 degree tests
Before you can decide whether section 6 applies, you need to understand exactly what the two tests measure. Get this wrong and you risk serving no notice at all, which can leave your whole project vulnerable to a neighbour’s objection later on.
The first test, often called the 3 metre rule, applies where you propose to excavate within 3 metres of a neighbouring building or structure, and the excavation will go deeper than the bottom of that neighbour’s foundations. Both conditions have to be true at the same time. Section 6 of the Party Wall etc. Act 1996 sets out that the horizontal distance and the depth condition must both be satisfied before the section applies, so a trench 2.5 metres away that stays well above the neighbour’s foundation level does not trigger the Act.
The second test extends the reach further out. If your excavation falls within 6 metres of the neighbouring building, section 6 still applies where a line drawn at 45 degrees from the bottom of the neighbour’s foundation, up to the external face of their wall, would be cut by your proposed excavation. This test exists because deep or heavy excavations further away can still undermine a neighbour’s ground support, even where the horizontal distance alone might seem safe.
Both tests demand accurate information about the neighbour’s foundations, which is rarely visible from the surface. You cannot estimate this by eye or from a tape measure alone. In practice, this means:
Establishing the neighbour’s foundation depth from existing drawings, historic building records, or a trial pit dug with appropriate consents.
Plotting the 45 degree plane accurately on a scaled section drawing, not a sketch.
Measuring your own excavation depth and distance from the boundary with the same precision you would use for structural calculations.
Checking both tests independently, since a project can trigger one, both, or neither depending on geometry.
A rear garden trench for new drainage might sit comfortably outside 3 metres but still fall inside the 6 metre and 45 degree zone if it is deep enough. A piled column foundation for an extension can trigger the 3 metre test even at a shallow depth if the neighbour’s foundations are unusually shallow, which is common in older Victorian terraces. A basement lightwell dug close to a boundary wall will almost always require careful checking against both tests, given the depths typically involved. None of these scenarios can be resolved with a rough guess, which is why RICS guidance on party wall legislation and procedure treats establishing the correct foundation datum as often the deciding factor in whether section 6 applies at all.
What to include in a section 6 notice and how to prepare the mandatory drawings
Once you have confirmed that section 6 applies, the next job is preparing a notice that will actually hold up. A large share of party wall disputes trace back not to the underlying excavation itself, but to a notice that was incomplete or badly drawn from the start.
The Gov confirms that a section 6 notice must set out your proposals clearly, state whether you intend to underpin or otherwise safeguard the neighbouring foundations, and be accompanied by plans and sections that show the site and the depth of the excavation. Unlike some other notices under the Act, drawings are not optional here. A written description alone will not satisfy the statutory requirement.
Your drawings and accompanying information should give a surveyor, or your neighbour, enough detail to judge the risk to their property without needing to ask follow-up questions. At minimum, prepare:
A scaled site plan showing the position of the proposed excavation relative to the boundary and the neighbouring building.
A cross-section drawing showing the existing foundation bottom level of the neighbouring structure, established from records or a trial pit.
The proposed excavation depth and its horizontal distance from the neighbour’s foundations.
A clear indication of underpinning or safeguarding works, if these are proposed as part of the scheme.
The neighbour’s building outline marked accurately on the drawings, not approximated from a satellite image.
Pro Tip: Commission your foundation-level survey before you finalise the notice drawings, not after; changing the depth data late in the process usually means redrawing everything and delaying service by weeks.
Notices should be served by, or on behalf of, the building owner, and can be signed by an agent such as a surveyor or architect acting with authority. Deficient service, whether through an incomplete address, a missing drawing, or a notice sent to the wrong party, can undermine the whole procedure and leave you exposed to a dispute claim later, even after work has started.
Timings, responses and deemed dissent: practical implications for your programme
Section 6 timings are unforgiving if you have not built them into your programme from the outset. Missing them by even a few days can stall a project that was otherwise ready to go.
You must serve notice with enough advance time before you intend to begin the excavation work. Your neighbour then has a limited period from receiving that notice to respond in writing. According to the GOV.UK explanatory booklet, if they do not give written consent within that window, they are deemed to have dissented, even if they never actually object to the work itself.
This deemed dissent is not a rejection of your project. It simply moves the matter into the Act’s formal dispute procedure, which exists precisely for situations like this.
Serve notice at least one month before excavation begins, allowing extra time for postal delays or holiday periods.
Track the 14 day reply window carefully, since silence counts as dissent under the Act.
Expect deemed dissent to trigger the section 10 surveyor and award process rather than stopping the project outright.
Watch the 12 month expiry: if work has not started, or is not being carried on with reasonable progress, the notice lapses and needs re-serving.
Build a buffer into your programme for the one month notice period plus time for a possible award, rather than assuming your neighbour will respond immediately, following expert compliance tips for construction to manage statutory notice windows effectively.
If there’s a dispute: appointing surveyors and the party wall award process
Once dissent, or deemed dissent, has arisen, the Act sets out exactly how to resolve it, and this is where many owners feel the process becomes daunting. In practice, it is a structured and fairly predictable route.
Section 10 of the Party Wall etc. Act 1996 allows the parties to appoint a single surveyor they both agree on, or for each owner to appoint their own surveyor. If the two surveyors cannot agree on a point between them, they select a third surveyor whose decision on that point is final. This structure means a dispute rarely needs to go anywhere near a courtroom.
The award will set out precisely what work is permitted and the method by which it must be carried out.
It typically specifies timing, working hours, and any access arrangements needed on the neighbour’s land.
It usually includes a schedule of condition recording the state of the neighbouring property before work begins.
It sets out how costs, including the surveyors’ fees, are to be apportioned between the parties.
Costs are generally paid by the building owner carrying out the works, since the neighbour did not ask for or benefit from them, though the award can apportion costs differently where appropriate. An award can be subject to appeal in the county court according to legal timeframes, so acting promptly matters if you believe the award is unworkable. RICS guidance stresses that using RICS-qualified surveyors reduces the risk of an award specifying a method statement that turns out to be impractical on site, since party wall surveyors are expected to understand construction sequencing as well as the legal framework.
Duties and liabilities: underpinning, making good and technical safeguards
Section 6 places real financial and practical obligations on the building owner, not just procedural ones. Understanding these before you start protects both your budget and your relationship with your neighbour.
Where an adjoining owner requires it, the Act obliges you to underpin, strengthen, or otherwise safeguard their foundations at your own expense, as set out in section 6 of the Act. This is not negotiable if the neighbour reasonably asks for it and the surveyors agree it is necessary given the works proposed. You also have a duty to avoid unnecessary inconvenience during the works and to make good any damage caused as a direct result of the statutory work.
Commission a pre-start condition survey, ideally with photographs, so there is a clear record of the neighbouring property’s condition before any excavation begins.
Set up a monitoring regime, particularly for basements or deep piling, so movement can be caught early rather than discovered after cracks appear.
Require detailed method statements from your contractor, covering sequencing, temporary works, and how they intend to protect the neighbour’s foundations.
Confirm adequate insurance is in place, covering both the works and potential damage to the adjoining property.
Pro Tip: Ask your surveyor to build access and inspection rights into the award itself; this avoids awkward on-the-spot negotiations with your neighbour once digging is underway.
A party wall award can specify exactly when and how you or your contractor may access the neighbour’s land to inspect or monitor the works, which removes ambiguity that might otherwise cause friction mid-project.
Practical steps before you start: gathering technical evidence and instructing surveyors
Getting section 6 right starts long before you pick up a shovel. The preparation stage is where most delays are either avoided or created.
Establish the neighbour’s foundation bottom level using whatever combination of existing building records, local authority archives, or a small trial pit gives you reliable data, rather than relying on assumption.
Commission scaled drawings and, where the excavation is deep or close to a boundary, temporary works information from a structural engineer, so your notice is backed by genuine technical substance.
Decide early whether to instruct a party wall surveyor yourself; for anything beyond a shallow trench, involving a RICS-qualified surveyor from the outset usually saves time overall.
Brief your surveyor with a clear scope: what you propose to build, the excavation depth and method, your intended programme, and any underpinning already anticipated.
Keep a running record of everything, including dated photographs of the boundary area, monitoring logs once works begin, and a written pre-start condition report.
A robust pre-start condition survey and contemporaneous photographic record reduce the risk of costly contested damage claims and make awards and post-work liability assessments straightforward.
Altura Surveyors provides party wall surveying services across Hampshire, Surrey, and Berkshire, covering notice preparation, condition schedules, and dispute support, with RICS-compliant reports typically delivered within 3 to 5 working days. Where access to roofs or boundary areas is difficult, drone roof inspections can add useful detail to a condition survey without the need for scaffolding.
Completion, records and what to do if the notice has expired
The obligations under section 6 do not end once the excavation is finished. What you keep on file afterwards matters just as much as what you prepared beforehand.
If requested, the building owner must supply particulars, plans, and sections relating to the completed work, so it is worth keeping these organised rather than scattered across different contractors’ files.
Retain the schedule of condition, all monitoring records, and any contractor completion reports in one place.
Keep dated photographs from before, during, and after the works, which prove invaluable if a dispute arises months later.
If work has not started within 12 months of the notice date, or has stalled without due diligence, do not assume the old notice still holds. Section 6 states the notice ceases to have effect, so seek professional advice and re-serve if necessary before restarting.
Practitioner perspective: common pitfalls and how professional surveying prevents delay
The notices that cause the most trouble are rarely the ones where a neighbour genuinely objects to the project. More often, it is a drawing missing a foundation level, a datum taken from the wrong reference point, or a section that does not actually show the depth being proposed. Any of these can invalidate a notice and send a straightforward extension back to square one.
Bringing in a party wall surveyor early, before the drawings are finalised rather than after a neighbour has already queried them, tends to prevent most of these issues. A clear instruction brief covering exactly what you propose and when saves several rounds of correspondence later. Fast, focused technical work, including targeted condition surveys and drone imagery where access is difficult, keeps a project moving rather than stuck waiting on paperwork.
— Paul
How Altura Surveyors can help with your section 6 requirements
Preparing a valid section 6 notice does not need to be a source of stress or a reason your project stalls for months. This surveying practice works exclusively as an independent surveying service, with no estate agency ties or upselling, meaning the advice given on party wall matters is focused entirely on the property and project.
Our party wall surveying service covers the full process, from establishing foundation levels and preparing notice drawings through to condition schedules, monitoring, and dispute support if a neighbour dissents. Where a condition survey benefits from a closer look at roofs or boundary structures, our drone roof inspections reach areas that would otherwise need scaffolding.
RICS-compliant reports written in plain English, typically delivered within 3 to 5 working days.
Local coverage across Hampshire, Surrey, and Berkshire, with surveyors who understand the housing stock in these areas.
Support with notice drafting, service, and the schedule of condition your neighbour will expect to see.
If you are planning excavation work near a boundary and want to check whether section 6 applies to your project, request a quote through our party wall surveying page and we will talk you through the next steps.
Key legislation and professional guidance
This article draws on the statutory text of section 6 and section 10 of the Party Wall etc. Act 1996, the GOV.UK explanatory booklet, and RICS professional guidance, each providing the legal basis, official interpretation, and practice standards behind the advice given.
This article is general information, not a substitute for advice from a qualified lawyer. Consult a qualified legal professional about your own circumstances before acting on anything here.
Sources
FAQ
What is section 6 of the Party Wall Act?
Section 6 of the Party Wall etc. Act 1996 covers excavation work near a neighbouring building, applying where you dig within 3 metres and below the neighbour’s foundation depth, or within 6 metres and inside a 45 degree plane measured from their foundation base. It requires a building owner to serve notice, backed by plans and sections, before starting the work, as set out in section 6 of the Act.
What is a section 6 notice?
A section 6 notice is the written notice a building owner must serve on an adjoining owner before excavating within the distances covered by the Act. It must state the proposals, confirm whether underpinning or safeguarding is intended, and include plans and sections showing the site and depth, as required by the GOV.UK explanatory booklet.
Can my neighbour stop me building on the party wall?
A neighbour cannot simply veto lawful work covered by the Act, but they can dissent or fail to respond, which is treated as deemed dissent. This moves the matter into the statutory dispute process under section 10, where appointed surveyors produce a binding award setting out how and when the work may proceed.
What is the legislation regarding party walls in the UK?
Party wall matters in England and Wales are governed by the Party Wall etc. Act 1996, which sets out notice requirements, excavation tests under section 6, and the surveyor and award process under section 10. The full statutory text is available on legislation.gov.uk, alongside the GOV.UK explanatory booklet for practical guidance.
