Planning a rear/side extension, a basement, a lightwell or rebuilding walls with new footings?
If your works dig close to a neighbour, Section 6 of the Party Wall etc. Act 1996 is likely in play. Here’s the clear, plain-English guide you can rely on.
What Section 6 Actually Covers
1) Section 6(1): The “3-Metre Rule”
Section 6(1) applies when both of these are true:
- You will excavate within 3 metres of any part of an adjoining owner’s building or structure; and
- Your excavation will go deeper than the bottom of their existing foundations.
If both tests are met, a Section 6 Notice is required.
2) Section 6(2): The “6-Metre / 45° Rule”
Section 6(2) extends protection to 6 metres where geometry shows likely influence:
- If any part of your excavation/foundation lies within 6 metres of the neighbour’s building/structure, and
- A line drawn downwards at 45° from the underside of their foundations would intersect your proposed excavation/foundation,
then a Section 6 Notice is required.
Practical read-across: deep piles, ground beams or basement formation often trigger 6(2) even when you’re more than 3m away.
Statutory Timing (Don’t Cut It Fine)
- Minimum notice period: 1 month before you start the excavation works (Section 6).
- Postage allowance: add 2 days if serving by post.
- If a dissent is returned (or there’s no response), surveyor appointment(s) and an Award will be needed before you dig—plan time in.
What a Good Section 6 Notice Should Include
To be valid and helpful, include:
- Clear location plans showing distances to the neighbour’s building/structures.
- Sections indicating proposed excavation depths relative to the neighbour’s foundation underside.
- Foundation type & outline method (e.g., trench fill, pads, piles & ground beams, raft).
- Programme (proposed start), and your contact/agent details.
- A statement of any special foundations (reinforced foundations) if proposed—note these require adjoining owner’s consent when they project onto/under their land.
The clearer the drawings and depth references, the faster surveyors can assess risk and move to an Award if needed.
Typical Projects That Trigger Section 6
- Basements and lightwells (almost always).
- Extensions with new strip/trench foundations near the boundary.
- Underpinning (your side or to a party wall).
- Piled foundations within the 3–6m bands.
- New retaining walls, garden rooms and outbuildings with deep pads near neighbours.
Interaction With Other Notices
- Building at or astride the boundary? You may also need a Section 1 notice (new wall at the line of junction).
- Cutting into / altering a party wall or party structure? You may also need a Section 2 notice.
- It’s common for well-designed schemes to require both Section 6 and Section 1/2—serve all that apply.
Access & Protections (How Works Actually Happen)
- If access to the neighbour’s land is reasonably necessary to carry out the notified excavation/foundation works, Section 8 access can be granted by the surveyor(s) via the Award.
- The Award typically sets out method safeguards (e.g., temporary support/shoring, keeping trenches open only as necessary, filling within specified hours/periods, protection to ground/surfaces, plant limits).
- For higher-risk excavations (e.g., basements), expect surveyors to rely on an advising engineer and, where justified, consider Security for Expenses (a refundable fund set aside to cover foreseeable risks—administered under the Act).
Common Mistakes (And How To Avoid Them)
- Guessing neighbour’s foundation depth
- Fix: make a reasonable, evidenced assumption (e.g., trial pit on your side, old records, comparable street depth) and show it on your sections. If in doubt, assume deeper—you’re safer serving than skipping a valid notice.
- Serving only Section 1 when digging deeper nearby
- Fix: if you’re within 3–6m and deeper than they are (or intersect the 45° line), serve Section 6 as well.
- Late notice service
- Fix: serve early (ideally when design is settled). If dissent arises, surveyor appointments + Award take time—don’t risk programme slippage.
- Vague drawings
- Fix: provide to-scale plans/sections showing finished formation levels, foundation types and construction sequence headline notes.
- Assuming a consent
- Fix: plan for a possible dissent. It isn’t personal; it’s how an adjoining owner secures surveyor input and a protective Award.
Worked Example (Quick Sense-Check)
- Your trench fill foundation: 2.0m deep.
- Neighbour’s estimated strip foundation underside: 1.0m deep.
- Distance wall-to-wall: 2.4m.
Section 6(1) applies (within 3m and deeper).
Serve a Section 6 Notice (and any other relevant notices), allow 1 month, and be ready for surveyor appointment(s) and an Award if the neighbour dissents or doesn’t reply.
Make Adjacent Excavations Straightforward
Want certainty on whether 6(1) or 6(2) is triggered?
Email team@simplesurvey.co.uk with your drawings. We’ll confirm which notices apply and outline the fastest route to an Award—before you book the digger.
Simple Survey — Fixed Nationwide Fees (RICS-Qualified)
| Service | What’s included | Fixed price* |
|---|---|---|
| Party Wall Notice (per Adjoining Owner) | Drafting, validity checks, correct service & response tracking | £25 |
| Agreed Surveyor Award | Single impartial surveyor; tailored protections; service of Award | from £300 |
| Building Owner’s Surveyor (two-surveyor route) | Liaison, protections, drafting & service of Award | from £325 |
*Complex schemes (e.g., basements, piles/ground beams) may require additional specialist input. We flag extras up-front—no surprises.
Nationwide • Fixed fees • RICS-qualified • Basement/loft/extension specialists
FAQ
Q1: I don’t know how deep my neighbour’s foundations are—what do I do?
Make a reasonable, evidenced assumption (trial pit on your side, historic data, typical local depths). If you’re likely deeper (or 45° intersects), serve Section 6. It’s safer to notify than to risk invalid process.
Q2: Do piles trigger Section 6?
Yes—piles and ground beams are usually deep and often within the 3–6m bands. They frequently fall under 6(1) or 6(2).
Q3: My excavation is 3.2m away but very deep—do I still need a notice?
Possibly under 6(2). If a 45° line from the neighbour’s foundation underside intersects your excavation/foundation within 6 metres, serve Section 6.
Q4: Can my neighbour refuse and stop my excavation entirely?
They can dissent, which triggers surveyor appointment(s) and a protective Award. The Act is enabling—it allows lawful works to proceed with safeguards, not to stop them arbitrarily.
Q5: When can I start digging?
Not before the 1-month minimum has run and, if there’s a dissent or no response, not before the Award is served. Starting early risks injunctions and cost.
Q6: I’m also building the wall right on the boundary—do I need another notice?
Yes—Section 1 for the new wall at the line of junction, plus Section 6 for the adjacent excavation (if triggered).
Have drawings ready and want a rapid check?
team@simplesurvey.co.uk — fast, friendly and RICS-qualified.