Why Rear Extensions Fall Under the Party Wall Act
Across London, many residential rear extensions trigger Party Wall procedures because they often involve
work on or close to a shared boundary or wall. Under the
Party Wall etc. Act 1996
,
you must usually serve a valid
Party Wall Notice
before construction begins if your extension design includes any of the following:
- Building up to or on the boundary line (Section 1)
- Cutting into or raising a shared party wall (Section 2)
- Excavating near a neighbour’s foundations (Section 6)
If any of these apply, adjoining owners must be formally notified. Once notices are served, neighbours have
14 days to consent or dissent. If they dissent (or fail to respond), a Party Wall Award must be agreed
before works can legally start. Our detailed guide
When do I need a Party Wall Surveyor?
explains these triggers in more detail.
At Hourican Associates, our Chartered
Party Wall Surveyors in London
manage the entire process — from serving compliant notices to agreeing Awards and
Schedule of Condition Surveys
— so your rear extension proceeds smoothly and legally.
How Our Party Wall Service for Rear Extensions Works
We handle every aspect of the Party Wall process for your extension, keeping your build on track and
helping to maintain good neighbourly relations.
-
Initial Consultation
We review your architect’s drawings and proposals to identify which sections of the Party Wall etc. Act
apply (Section 1, 2 and/or 6) and which adjoining owners need to be served notice.
-
Serving Party Wall Notices
We prepare and issue correctly drafted
Party Wall Notices
to all affected neighbours, ensuring they are valid, clear and compliant with the Act. We can also advise
on how best to introduce the process to your neighbours to keep things amicable.
-
Schedule of Condition Survey
Before works start, we undertake a detailed
Schedule of Condition Survey
of adjoining properties — including written notes and photographs. This provides an objective record of
existing condition and is invaluable if damage is alleged later.
-
Preparing the Party Wall Award
Where a neighbour dissents or is deemed to dissent, we prepare a legally binding Party Wall Award. This
sets out how the rear extension works will proceed, including construction methods, access to neighbouring
land, working hours, protection measures and damage/repair procedures. Where appropriate, we can act as an
impartial surveyor for the building owner
and advise adjoining owners on their rights.
-
Post-Work Review
Once your extension is complete, we can revisit the neighbouring property to confirm whether any damage has
occurred and advise on remedial works in line with the agreed Award.
Transparent Fixed Fees for Rear Extension Party Wall Surveys
Our Party Wall Surveys for rear extensions typically range from
£1,100 – £1,500 + VAT, depending on the size and complexity of the property and the
number of adjoining owners involved.
If your project only requires a
Schedule of Condition Survey
,
fees usually range from £385 – £585 + VAT. All fees are agreed in advance with no hidden
extras, and you can request an estimate via our
online Party Wall surveyor quote form.
In most cases, the Building Owner (the person carrying out the extension works) is responsible for the
reasonable Party Wall Surveyor fees — including those of the adjoining owner’s surveyor where appointed.
Why Choose Hourican Associates for Rear Extension Party Wall Surveys
Hourican Associates is a specialist Chartered Building Consultancy focused on residential Party Wall matters
throughout London. We combine technical expertise with clear, practical advice to help rear extension projects
progress without unnecessary delay or dispute.
- Chartered Building Consultancy regulated by RICS, CIOB and MCABE
- Members of the Faculty of Party Wall Surveyors (FPWS) and the Pyramus & Thisbe Society
- Specialists in residential extensions across all London boroughs
- Fast, impartial and legally compliant service with fixed, transparent fees
Our experience on hundreds of London extension projects means we anticipate common issues early, prevent
unnecessary disputes and deliver seamless compliance with the Party Wall Act. For more background information,
visit our
Party Wall FAQs
or read
Understanding Party Wall issues and how surveyors save you thousands
.
We regularly act as Party Wall Surveyors for extensions in
Chelsea,
Kensington,
Fulham,
Chiswick,
Westminster
and all areas across London.
Rear Extension Party Wall – Frequently Asked Questions
Yes — if your rear extension affects a shared wall, involves excavation within 3 metres of a
neighbour’s structure, or builds up to or on the boundary line, you will usually need to serve a
Party Wall Notice.
Many single-storey and wrap-around extensions in London fall under Sections 1, 2 and/or 6 of the
Party Wall etc. Act 1996
.
You must serve Party Wall Notices at least
one month before excavation works and
two months before structural works to a party wall or boundary begin. We
recommend serving notice as early as possible to allow time for surveyor appointments,
Schedule of Condition Surveys
and agreement of the Party Wall Award before your planned start date.
If your neighbour does not reply in writing within 14 days, they are deemed to have dissented
under the Act. A Party Wall Surveyor will then need to be appointed to represent them so that a
Party Wall Award can be agreed. In many cases, we can act as an
impartial surveyor to protect the adjoining owner’s rights
while keeping your project moving.
The Building Owner — the person carrying out the rear extension works — is normally responsible
for all reasonable Party Wall Surveyor costs. This usually includes their own surveyor’s fees and,
where separate surveyors are appointed, the adjoining owner’s surveyor’s reasonable fees as well.
Yes — with your neighbour’s consent, we can act as the
Agreed Surveyor
for both parties, providing a fair, cost-effective and impartial solution under Section 10(1)(a)
of the Act. This can simplify the process, reduce costs and still protect the rights of both the
building owner and adjoining owner.
Book a Party Wall Survey for Your Rear Extension
Avoid costly delays and disputes by getting expert Party Wall advice before you start building. Contact
Hourican Associates on 020 8050 3232, use our
online Party Wall surveyor quote form
or get in touch below for a free, no-obligation quotation.
Request a Free Party Wall Quote
Hourican Associates is a Chartered Building Consultancy regulated by RICS, CIOB and MCABE, and a member of
the Faculty of Party Wall Surveyors (FPWS) and the Pyramus & Thisbe Society. This page provides general
guidance only and should not be treated as legal advice.
