Party wall notices for extensions in Hertfordshire

Hertfordshire at a glance

Nation: England
Price region: East of England
Postcode areas: AL, CM, EN, HP, SG, WD
Towns covered: 33 listed below, plus surrounding villages
Site visits: Free, no obligation

What a party wall notice involves

This service suits you if your two-storey extension is close to a neighbour's house, wall or boundary. You get a check of which notices your work needs, the notices prepared and served with the right drawings, a timetable that builds in the notice periods, and help with a surveyor if your neighbour dissents.

Hertfordshire towns we list: Watford (WD1), Hemel Hempstead (HP1), Stevenage (SG1), St Albans (AL1), Welwyn Garden City (AL6) and Cheshunt (EN7). Every other address in Hertfordshire is covered as well.

Fees

We confirm every fee in writing before the design stage starts; typical professional fees are on our prices page.

Rules in England

In England, the Party Wall etc. Act 1996 applies. Notices are needed for a new wall on the boundary (1 month), work to a party wall (2 months) and nearby excavation (1 month). If a neighbour dissents, surveyors settle the terms; one agreed surveyor typically costs £1,300–£1,500 plus VAT, normally paid by the building owner.

Approval in England: Householder planning application: £548 (or £575 for applications made from 8 December 2026). Lawful development certificate: £274 (about £288 for applications from 8 December 2026). Councils should decide householder applications within 8 weeks of validation.

Building regulations: Building regulations approval (full plans recommended) from the council or a registered building control approver, with a completion certificate at the end.

Getting the design right

Building the timing in

Notice periods add to the programme, and a dissent can add more while surveyors agree the terms. We serve notices once the design and foundations are known, usually while planning is being decided, so they run in parallel with other approvals.

Talking to neighbours first

A conversation before the notice arrives often makes the difference between consent and dissent. We explain the work, share the drawings and answer questions, so neighbours know what to expect and are more likely to agree.

How we work in Hertfordshire

Measure and listen
A visit to Hertfordshire to understand how you live in the house now and what the extra rooms need to do, plus a first look at the structure.
Plans, then approval
Measured survey, design, then the right approval route for your house. We explain each step before we take it.
Detail and price
Construction drawings, engineer's calculations and building control sign-off, then a written fixed price for the build.
Build and hand over
We manage the build from groundworks to decoration-ready finish and hand over with the completion paperwork.

Towns we cover in Hertfordshire

Party wall notices for extensions in Hertfordshire: questions

What happens if my neighbour does not respond to a party wall notice?

For a party structure notice or an excavation notice, a neighbour who does not respond within 14 days is treated as having dissented. Surveyors are then appointed to agree a party wall award, which sets out how the work will be done and records the condition of the neighbour's property. Either one agreed surveyor or one for each side can act.

Can my neighbour stop my extension with the Party Wall Act?

No. The Party Wall etc. Act 1996 sets out how work is done and how neighbours are protected, but it does not let them block lawful work that has planning approval or is permitted development. It can delay the start if notices are served late, which is why we serve them early.

Neighbouring areas

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