Contracts

Party wall notices: what a builder must serve and when

15 October 2026 13 min read

The short answer

Under the Party Wall etc. Act 1996, which applies in England and Wales only, the building owner must serve written notice on every adjoining owner before three kinds of work: building a new wall on or at the boundary line (section 1, at least one month before), work to an existing party wall or party structure, such as cutting in a beam (sections 2 and 3, at least two months before), and excavating within 3 metres of a neighbour’s building to below their foundations, or within 6 metres where the dig cuts a 45 degree line down from them (section 6, at least one month before). The neighbour has 14 days to consent in writing. For party structure and excavation notices, silence is a deemed dispute, settled by surveyors in a party wall award under section 10. Those notices lapse if the work has not begun within twelve months.

At a glance

Extent: England and Wales only (s.22(4))
New wall at the boundary: At least 1 month’s notice (s.1)
Work to a party wall: At least 2 months’ notice (s.3)
Excavation: Within 3 m, or 6 m at 45 degrees: 1 month (s.6)
Neighbour’s reply: 14 days, or a dispute is deemed (ss.5, 6(7))
Counter notice: Within 1 month of the notice (s.4)
Notice lapses: Work not begun within 12 months (ss.3(2), 6(8))
Appeal against an award: 14 days, county court (s.10(17))

Who has to serve a party wall notice: the builder or the homeowner?

The building owner. Section 20 of the Act defines the building owner as the owner of land who wants to exercise rights under the Act, which on a domestic job is your client. The adjoining owner is the owner of the land, building, storey or room next door, and for excavation work, any owner within the 3 or 6 metre distances, even if another property sits between you.

‘Owner’ is wider than the freeholder. The government’s explanatory booklet says it includes a leaseholder with more than a year left and someone under contract to buy, so one house can have more than one owner, and every one of them must be served. A building split into flats can mean several owners to serve for one wall.

Builders often draft the notices, and the booklet allows a notice to be given on the owner’s behalf. It still has to be the owner’s notice: their name and address, with joint owners all named. Planning permission and Building Regulations approval do not replace it, and the booklet says so plainly. See do you need planning permission for an extension? for that separate question.

Failing to serve is a civil matter, not a criminal offence, but the adjoining owner can go to court for an injunction to stop the work. An injunction stops the job on site, whoever forgot the notice.

Which work needs a party wall notice?

Three kinds, and one job can need more than one notice. A party wall is a wall standing on the land of two owners, or a wall on one owner’s land used by both to separate their buildings. A party structure is wider: a party wall, or a floor or other structure separating buildings or parts of buildings with separate entrances, such as flats.

Section	Work	Typical examples	Minimum notice
s.1	A new wall on the line of junction, astride it or wholly on your side	A new flank wall built up to the boundary; a garden wall on the line	One month
ss.2 and 3	Work to an existing party wall or party structure	Cutting in a beam bearing or a DPC, underpinning, raising, removing a chimney breast, cutting in a flashing	Two months
s.6	Excavating within 3 m of a neighbour’s building to below their foundations, or within 6 m where the dig meets a 45 degree line down from their foundations	Trench foundations for a rear extension, a basement, a pile cap near the boundary	One month

Notice periods from sections 1(2), 1(5), 3(2)(a) and 6(5) of the Party Wall etc. Act 1996.

Some work is too minor to need notice. GOV.UK gives plastering, adding or replacing wiring or sockets, and drilling to put up shelves or cabinets. The booklet’s test is whether the work could affect the wall’s strength or support, or damage the neighbour’s side. A timber fence is not a party fence wall.

Loft conversions often need a section 3 notice, because cutting into the party wall to take a beam is one of the booklet’s own examples. See how to price a loft conversion.

What must a party wall notice say, and how is it served?

There is no official form, but the content is set by the Act. Date the notice and say it is served under the Party Wall etc. Act 1996.

Party structure notice (section 3). The building owner’s name and address, the nature and particulars of the work, and the date it will begin. Special foundations need plans, sections and details, with the loads they will carry.
Excavation notice (section 6). Your proposals, whether you intend to underpin or otherwise strengthen or safeguard the neighbour’s foundations, and plans and sections showing the site and depth of the excavation and the site of any new building.
Line of junction notice (section 1). That the owner wants to build, and a description of the intended wall, saying whether it is to stand astride the line or wholly on the owner’s land.

Section 15 allows service by hand, by post to the person’s usual or last-known address, or by email, but email only where the recipient has said they will accept notices that way and given an address. Where the owner is unknown, a notice can be addressed to ‘the owner’ of the premises and handed to someone there, or fixed somewhere conspicuous if nobody is there. Keep a copy of every notice and a note of when and how it went.

How long before work must each notice be served, and when does it lapse?

One month before the work starts for a new wall at the line of junction or an excavation, and two months for work to a party structure. The booklet says the owner must wait the full period unless the adjoining owner agrees in writing to an earlier start.

A party structure notice and an excavation notice cease to have effect if the work has not begun within twelve months of service and is not being carried on with due diligence (sections 3(2)(b) and 6(8)). For a new wall, the right to put projecting footings under the neighbour’s land runs from one month to twelve months after service (section 1(6)), and the booklet treats every notice as valid for a year.

Serve too late and the start date slips. Serve too early and the notice can lapse before you dig. Put the notice dates on the programme with the same weight as a material lead time.

For scheduling, see how to build a construction programme for a small job.

What happens after the notice is served?

The adjoining owner can consent in writing, dissent, serve a counter notice, or do nothing. What silence means depends on which notice it is.

Party structure and excavation notices. No written consent within 14 days, beginning with the day of service, and the owner is deemed to have dissented and a dispute is deemed to have arisen (sections 5 and 6(7)).
A new wall astride the line. No written consent within 14 days and the building owner may only build the wall wholly on their own land, at their own expense (section 1(4)).
A new wall wholly on your own land. The booklet says work can start after the one-month period if the neighbour does not respond.
Counter notice. Within one month of a party structure notice, the neighbour can ask for extra works for their own benefit, such as chimney breasts, piers or deeper special foundations (section 4). You have 14 days to consent to it, or a dispute is deemed. The neighbour pays for works done at their request.

NoteConsent is not a waiver. The booklet says it only confirms nothing is in dispute at that time. Your duties on protection and damage stay, and a later disagreement, over damage for example, goes through the dispute procedure.

How do party wall surveyors and the award work?

Under section 10, the owners either agree on one surveyor, the agreed surveyor, or each appoints their own, and those two select a third. Appointments must be in writing and cannot be rescinded. If one owner refuses to appoint, or neglects to for 10 days after being asked, the other can appoint a surveyor on their behalf.

A surveyor is anyone who is not a party to the matter. GOV.UK says you cannot act as your own surveyor, and the booklet says the surveyor should not already be engaged to supervise the building work, which rules out the builder running the job.

The surveyors settle the dispute in a party wall award. It can decide the right to do the work, the time and manner of doing it, and anything incidental, including the costs of making the award (section 10(12)). The booklet adds that it often records the condition of the neighbour’s property before work starts. The surveyors decide who pays their costs, and the booklet says the building owner usually pays all of them where the work is solely for the building owner’s benefit.

An award cannot start the work before the notice period has run, unless the owners agree otherwise.
The award is conclusive. Either owner can appeal to the county court within 14 days of it being served on them (section 10(17)).
The Act does not settle where the boundary is. A boundary dispute is a separate matter.

What do you owe the neighbour once work starts?

Section 7 sets the duties, and the award usually adds detail. The booklet says the building owner is legally responsible for damage even where the contractor caused it, so your client will look to you.

No unnecessary inconvenience to the adjoining owner or occupier (section 7(1)).
Compensation for any loss or damage resulting from the work (section 7(2)). The neighbour can ask for payment in place of making good (section 11(8)).
Protection. Where you lay open their land or building, a proper hoarding, shoring or temporary construction, at the building owner’s expense (section 7(3)).
No special foundations on their land without their written consent (section 7(4)).
No deviation from the agreed or awarded plans and sections without agreement or a further award (section 7(5)).
Access. Workers and surveyors may enter the neighbour’s land in usual working hours to do the notified work, after at least 14 days’ notice except in an emergency (section 8). The booklet says obstructing lawful entry is an offence.
Security. The neighbour can ask for security for expenses before work starts, settled by the surveyors if not agreed (section 12).

Under section 11(1) the building owner pays for the work, except where the neighbour shares the cost of repairing a defect or asks for extra work. In your quote, put the party wall surveyors’ fees, anything the award adds (protection, monitoring, underpinning the neighbour’s foundations) and any delay from the notice periods in the exclusions or as stated allowances. See is a builder’s quote legally binding?

Photograph the neighbour’s side before you start and record visits, access and any complaint on the day it happens. See how to keep a site diary that holds up in a dispute.

What does a party wall timeline look like on a rear extension?

A semi-detached house is getting a single-storey rear extension. The trench foundations are 1 metre from the neighbour’s rear wall and go deeper than the neighbour’s foundations, so section 6 applies. A steel over the new opening bears on a pocket cut into the party wall, so section 3 applies too. Both notices are served by hand on the same day.

01Confirm every adjoining owner from the title, freeholder and any leaseholder included.
02Serve the section 6 notice with plans and sections, and the section 3 notice, on each of them.
03Wait 14 days for written consent.
04If there is no consent, ask the neighbour to agree a surveyor or appoint their own, and appoint yours.
05Let the surveyors make the award and serve it, then allow the 14-day appeal period.
06Give 14 days’ notice of any entry onto the neighbour’s land the work needs.
07Start the excavation no earlier than one month after service, and cut the party wall no earlier than two months after service, unless the neighbour agrees in writing to an earlier date.

Day	Event	Under
1	Section 3 and section 6 notices served	ss.3, 6, 15
14	Last day for written consent to either notice	ss.5, 6(7)
15	No reply: a dispute is deemed on both notices	ss.5, 6(7)
15 onwards	Request to appoint a surveyor; if ignored for 10 days, the building owner appoints one on the neighbour’s behalf	s.10(4)
About 30	Last day for a counter notice (one month from service)	s.4(2)(b)
One month after service	Earliest start for the excavation, with the award in place	ss.6(5), 10(12)
Two months after service	Earliest date to cut into the party wall for the steel	ss.3(2)(a), 10(12)
Twelve months after service	Both notices lapse if work has not begun	ss.3(2)(b), 6(8)

Illustrative timeline for a worked example, counted from the day of service. When the award arrives depends on the surveyors.

The two-month notice sets the pace. If the programme has the steel going in during week six, serve the section 3 notice earlier or get the neighbour’s written agreement to an earlier date. The cost side of the same job is in how to price a house extension.

Free toolUK construction glossaryParty structure, award, adjoining owner and the other terms on a notice, defined in a sentence each.

How does Estimark help with party wall work?

Estimark’s quote goes out on your letterhead with your own terms, and the client accepts and signs it online, so the party wall exclusions and any start date that depends on the notices are in the document they signed. See quotes and online acceptance.

The correspondence log keeps each notice served and each reply received against the job, with the direction, date, sender, recipient and subject, tags to pull the party wall papers out later, and the signed copies attached. It does not serve notices or appoint surveyors.

Sources

Questions

Frequently asked

Can building work start before the party wall notice period ends?

Only if the adjoining owner agrees in writing to an earlier start. Otherwise wait one month after service for a new wall at the boundary or an excavation, and two months for work to a party wall or party structure.

What happens if the neighbour ignores a party wall notice?

For work to a party wall or an excavation, no written consent within 14 days means a dispute is deemed and surveyors settle it in an award. For a new wall astride the boundary, silence means the wall must be built wholly on the building owner’s land at their expense.

Does a loft conversion need a party wall notice?

Often, yes. Cutting into a party wall to take the bearing of a beam is work under section 2, and the party structure notice under section 3 must be served at least two months before that work starts.

Can the builder act as the party wall surveyor?

Not on their own job. A surveyor under the Act must not be a party to the matter, and the government’s booklet says the surveyor should not already be engaged to supervise the building work.

Does the Party Wall Act apply in Scotland or Northern Ireland?

No. Section 22(4) says the Act extends to England and Wales only, and the government’s booklet confirms it does not apply in Scotland or Northern Ireland, which have their own rules.

Does planning permission or Building Regulations approval remove the need for a party wall notice?

No. The Act is separate from both. A job can need planning permission, Building Regulations approval and party wall notices, or any one of them on its own.

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