The Party Wall etc. Act 1996 is not a planning tool — it is a civil framework that protects neighbouring owners from damage during construction and gives you, the building owner, a legal right to carry out specified works. Ignoring it does not make the works illegal; it makes them uninsurable and exposes you to a Section 21 injunction that can stop your build for months.
Step 1 — Work out whether the Act applies
Three types of work trigger a notice. Any one of them is enough.
| Section | What triggers it | Notice period | Typical London case |
|---|---|---|---|
| Section 1 — Line of junction | Building a new wall on or up to the boundary where none exists | 1 month | Side return extension wall built up to the boundary |
| Section 2 — Works to a party wall | Cutting into, raising, underpinning or removing part of a shared wall | 2 months | Beam bearings cut into the party wall; roof tied into the neighbour's flank |
| Section 6 — Adjacent excavation | Excavating within 3 m and below the neighbour's foundations, or within 6 m under a 45° line | 1 month | Almost every London rear extension foundation |
Step 2 — Identify every adjoining owner
- Both attached neighbours on a terraceAlways
Left and right, for Section 2 and Section 6 works.
- Freeholder and every leaseholderCommon in London
In converted flats, each leasehold owner with an interest over 12 months must be served separately.
- Rear or diagonal neighboursCheck
Only if excavation falls within 3 m / 6 m of their structure. Check the site plan, not your intuition.
- Absent or unknown ownersFallback
Serve to 'The Owner' at the property address and to the registered proprietor from HM Land Registry (£7).
- Managing agent for a blockIf applicable
Serve the agent and the freeholder; note the agent is not automatically the owner.
Step 3 — Serve the notice properly
Notices are one to two pages, must be in writing, and must include your name and address, a description of the works, the proposed start date and drawings showing what is being done. Templates in the government's Party Wall etc. Act 1996: Explanatory Booklet are the safest starting point.
- 1
Have the drawings ready first
Before servingStructural engineer's foundation section and beam bearing details. A notice without drawings reads as vague and gets dissented almost every time.
- 2
Speak to the neighbour in person
Same weekTell them a formal letter is coming, that it is a legal requirement, and that it protects them. Warn them their surveyor's fee is paid by you.
- 3
Serve in writing, keep proof
Day 0Hand-deliver with a witness, or post with proof of posting, or email only if they have agreed in writing to email service. Note the date — the clock runs from service.
- 4
Include a consent option
Day 0Attach a tick-box consent/dissent reply slip and a stamped return envelope. Friction is the enemy of consent.
- 5
Chase at day 10
Before day 14A polite reminder before the 14-day deadline converts many would-be dissents into consents.
- 6
If silent at day 14, serve a further notice
Day 14Offer to appoint a surveyor on their behalf. If they do not respond within 10 further days, you appoint one for them.
Step 4 — Handle their response
| Response | What happens next | Typical London cost |
|---|---|---|
| Consent in writing | No Award needed. Commission a schedule of condition anyway. | £0–£500 |
| Dissent, agreed surveyor | One surveyor acts for both owners and issues a single Award. | £900–£1,600 |
| Dissent, own surveyor | Two surveyors act jointly; a third is selected in case of deadlock. | £1,600–£3,500 |
| No response in 14 days | Deemed dissent. You serve a further notice and may appoint for them. | £1,200–£2,200 |
Step 5 — Read the Award before you countersign
An Award is a legal document binding both owners. Check it contains:
- A precise description of the notifiable works — matched to your engineer's drawings.
- A method statement, including sequencing of underpinning or needling.
- A schedule of condition with dated photographs of every visible surface next door.
- Working hours — usually 8am–6pm Mon–Fri, 8am–1pm Sat, none on Sundays or bank holidays.
- Access rights, including the notice period required before entering the neighbour's property.
- A damage repair mechanism, and whether making good is in cash or in kind.
- Security for expenses, if requested — check the amount is proportionate before you agree.
Step 6 — Run the process alongside planning, not after it
Nobody has ever been injuncted for serving a notice too early. Plenty of people have been injuncted for starting a week before the Award.
— Every party wall surveyor in London, eventually
Neighbourly practice that also protects you legally
- Speak to neighbours before serving — a pre-warned notice consents far more often than a cold one
- Share the builder's programme in writing; unpredictable noise is the real complaint
- Commission a schedule of condition even for consenting neighbours
- Keep dust and mud off their steps, railings and cars, every single day
- Give one named contact and mobile number for the whole build
- Post a bare notice through the letterbox with no conversation
- Serve without drawings or with a fantasy start date
- Start excavation before the Award is in place
- Let the builder negotiate directly with the neighbour about damage
- Assume a consenting neighbour cannot claim later — without a schedule of condition, they can
Two mistakes that stop a build
- Starting before the Award is in place. Your neighbour can apply for a Section 21 injunction and the court will grant it. Realistic damage: 6–12 weeks of delay and £5,000+ in legal fees, plus your builder's standing-time claim.
- Serving a notice with insufficient detail. Neighbours and their surveyors treat vague notices as a reason to dissent. Include drawings, a clear works description and a realistic start date.
+Who pays the party wall surveyor?
The building owner — you — pays your own surveyor and the adjoining owner's reasonable fees, because the works are for your benefit. Fees can be challenged as unreasonable, but expect to pay both.
+Can my neighbour refuse the works outright?
No. Dissent triggers the surveyor process, which produces an Award setting out how the works proceed. The Act gives you a right to carry out notifiable works subject to that Award.
+Do I need a notice if I'm only digging foundations?
Usually yes. Section 6 applies to excavation within 3 m of a neighbouring structure and deeper than their foundations, which covers nearly every London rear extension.
+How long is a notice valid?
Twelve months from service. If you have not started within a year, serve again.
+Do I need a party wall surveyor if the neighbour consents?
Not legally, but commission a schedule of condition. Without dated photographs, you carry the risk of any pre-existing crack being attributed to your build.
+Does the Act apply to flats?
Yes. Serve the freeholder and each leaseholder with an interest longer than a year — in London conversions that often means three or four notices for one building.