When Do I Need a Party Wall Agreement?
Hourican & Associates Ltd |
Planning building works in London? Certain projects that affect a shared wall, boundary, or nearby foundations require a Party Wall Agreement (also called a Party Wall Award) under the Party Wall etc. Act 1996. This guide explains when you legally need one, how the process works, and why using a chartered party wall surveyor in London helps avoid costly delays and disputes.
What Is a Party Wall Agreement?
A Party Wall Agreement is a legally binding document prepared by an appointed surveyor that regulates how works affecting a shared or adjoining structure are carried out. It typically sets out:
- The exact works permitted and methods of construction.
- Working hours and access arrangements.
- A Schedule of Condition of the adjoining owner’s property pre-works.
- Procedures for resolving disputes and making good any damage.

When Do You Need to Serve a Party Wall Notice?
Before starting any notifiable works, you must serve the correct notice(s):
1) Works to a Party Wall or Party Structure — Section 2 Notice
- Cutting into a party wall (e.g. inserting steel beams for a loft conversion).
- Removing or enclosing a chimney breast attached to a shared wall.
- Raising, thickening, underpinning, or demolishing a party wall.
- Inserting flashing or damp-proof courses.
2) Excavation Near Neighbouring Foundations — Section 6 Notice
- Excavating within 3 metres of a neighbouring structure to a lower level than its foundations.
- Excavating within 6 metres where piling or deep foundations trigger the 45° line criteria.
Common examples: rear/side extensions with deep foundations, underpinning, and basement construction.
3) New Walls on or at the Boundary — Section 1 Notice
- Building a new wall on the line of junction (boundary).
- Building a new wall astride the boundary (requires neighbour’s written consent).
- Constructing a new party fence wall (e.g. a garden wall built on the boundary).
Do You Always Need a Full Party Wall Agreement?
If you serve a valid notice and your neighbour consents in writing within 14 days, an Award may not be required. If they dissent or do not reply within 14 days, a dispute is deemed to have arisen under the Act and surveyor(s) must be appointed to agree a formal Award.
Why Use a Chartered Party Wall Surveyor?
- Correct, legally valid notices under the Act.
- Independent, impartial administration of the process.
- Robust Schedule of Condition to protect all parties.
- Clear procedures for access, method statements, and damage resolution.
Hourican Associates are regulated by RICS, and members of the FPWS, CIOB, and MCABE.
Typical London Projects That Trigger the Act
- Loft conversions involving steel beams.
- Rear and side extensions.
- Basement excavations and underpinning.
- Chimney breast removals.
- New boundary or party fence walls.
Transparent Fixed Fees
Party Wall Notice Service
£150 + VAT
Per adjoining owner
Schedule of Condition Survey
£385–£585 + VAT
Basement surveys priced separately
Full Party Wall Award
£1,100–£1,500 + VAT
Serving notice, survey & agreeing the Award
London Areas We Cover
We work across all London boroughs including:
Chelsea, Kensington, Fulham, Chiswick, Clapham, Richmond, Westminster & more.
Frequently Asked Questions
Section 2 (works to party structures) and Section 6 (excavations): at least 2 months. Serve notices early to accommodate surveys and Award preparation.

Richard Hourican, Company Director
BSc (Hons). HND Build. MCIOB. C.Build E MCABE. ARICS. MFPWS. MPTS
As a specialist Party Wall surveyor, Richard Hourican will protect your interests during building works.
Are you planning a building project – perhaps an extension, loft conversion or basement – that is on or adjacent to your property’s boundary line? Or has a ‘Party Wall’ notice dropped on the doormat informing you of a neighbour’s impending works?
It’s essential to understand all the implications of building plans. If you don’t, it could cost thousands. Our job is to ensure everything is done correctly – and that it doesn’t!
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