Party Wall Services. Handled by Professional Surveyors.
Planning building works? LENIO prepares and serves your Party Wall Notice in London under the Party Wall etc. Act 1996, whether it is a Section 1, Section 3 or Section 6 notice, confirming exactly which your project needs and serving it correctly on every affected neighbour. Every notice is handled personally by a Chartered Civil and Building Engineer (ICE and CABE).
Planning an extension, loft conversion or basement works in London? LENIO identifies the correct notice, prepares it to the requirements of the Party Wall etc. Act 1996 and serves it on your behalf.
A Party Wall Notice is a formal document served on a neighbouring property owner before certain building works begin. It is a legal requirement under the Act, not an optional courtesy.
Importantly, a notice is not a request for permission. It is a notice of intent. You are not asking whether you may build. You are fulfilling a statutory duty to tell your neighbour what is planned so that both properties are protected.
The notice informs your neighbour of the proposed works, the intended start date and their rights under the Act. Once served, your neighbour has 14 days to respond. Their response determines the next stage of the party wall process.
Serving the correct notice at the right time is the first and most important step for any Building Owner in London.
Not all building work requires a Party Wall Notice. However, many common London renovation projects do fall under the Act. Confirming whether your project is notifiable is the right first step before any work begins.
Rear and side extensions that involve excavation near a neighbouring foundation or construction close to a boundary line often require notice. This is one of the most common notifiable projects in London.
Inserting steel beams into a party wall involves works carried out under section 2 of the Act, notified by a Party Structure Notice under section 3. Most loft conversions in terraced or semi-detached London properties require this notice.
Excavation near neighbouring structures triggers Section 6 of the Act. Basement works carry the highest party wall risk and require notice before any digging or foundation work begins on site.
Removing a chimney breast built into a party wall affects the shared structure. A Party Wall Notice must be served on the Adjoining Owner before this work begins.
Building a new wall at or near the boundary falls under Section 1 of the Act. This includes garden walls, new structures and any works on an existing shared boundary line.
Cutting into, raising, thickening or underpinning a party wall involves works carried out under section 2 of the Act. These are notified by a Party Structure Notice under section 3 before works begin.
The Party Wall etc. Act 1996 covers three distinct types of works, each requiring a different notice. Serving the wrong notice, or missing one entirely, can invalidate the process and delay your project.
A Section 1 notice applies to new walls built at or on the boundary line between two properties. One month's notice is required before works begin. This notice is commonly needed for new garden walls and boundary structures.
A Section 3 notice applies to works on an existing party wall or shared structure. Two months' notice is required before works begin. Loft conversions, chimney breast removals and structural alterations to shared walls typically require this notice.
A Section 6 notice applies to excavation within 3 metres or 6 metres of a neighbouring structure, depending on the depth of the works. One month's notice is required. Basement works and deep foundation projects most commonly trigger this notice. Drawings showing the depth and position of the excavation must accompany the notice.
A notice that omits any of these details can be treated as defective. If that happens, a fresh notice must be served and the full statutory period starts again from zero.
The description matters more than people expect. A vague line such as "some building work" is not sufficient, and a neighbour can later argue they never understood the scope of what was proposed.
An invalid notice has no legal effect at all. Everything built on top of it, including any Award, can be challenged.
A Party Wall Notice must be served on every affected Adjoining Owner. Under the Act, that means anyone with an interest in the neighbouring property greater than a yearly tenancy. In practice this includes freeholders and leaseholders with more than a year remaining on their lease.
In a block of converted flats, this can mean serving several people: each affected leaseholder and the freeholder who owns the building. Where a property is jointly owned, every joint owner must be named. Missing any one of them leaves the notice defective for that owner.
Serving notice on "the occupier" is one of the most common errors we see. A tenant renting short term is usually not the Adjoining Owner for the purposes of the Act, so a notice addressed to them alone has no legal standing.
For this reason we carry out Land Registry checks as part of the initial review, confirming exactly who holds an interest in each affected property before any notice is drafted. It is a small step that removes one of the biggest causes of delay.
The Party Wall etc. Act 1996 sets fixed notice periods for each type of notice. These cannot be shortened without the written agreement of your neighbour. Planning ahead is the most practical way to avoid delays to your project.
A Section 1 notice and a Section 6 notice each require one month's notice before works begin. The notice period starts from the date the notice is correctly served on the Adjoining Owner, not from the date it is prepared.
A Section 3 notice requires two months' notice before works begin. This is the most common notice period for London renovation projects, as most loft conversions and structural works on shared walls fall under Section 3.
A notice is only "served" when it reaches the Adjoining Owner by a method the Act permits. The method matters as much as the wording, because a notice that was never validly served has no effect.
Generally the most reliable route and well recognised. Posting to the Adjoining Owner's address starts the clock without requiring anyone to be at home.
Valid, but you need to be able to evidence it. Delivering in person or through the letterbox works provided the date and manner of delivery are properly documented.
Only valid where the Adjoining Owner has confirmed in writing that they are willing to receive notices electronically at that address. Without that agreement, an emailed notice does not count.
Serving the notice sets the process in motion. From that point, there are three possible outcomes and each one leads to a different next stage. Your neighbour has 14 days to respond, and their response determines how the party wall notice process continues.
Your neighbour agrees to the proposed works in writing within 14 days. The process moves forward without the need for surveyor appointments. Works may then proceed, though a Schedule of Condition is still advisable before construction begins.
Your neighbour formally objects to the proposed works. This does not stop the project. Instead, it triggers the statutory dispute resolution process under the Act and surveyors are appointed to prepare a Party Wall Award.
If your neighbour does not respond within 14 days, a dispute is treated as having arisen under the Act. This is known as deemed dissent. Surveyors must then be appointed even without a formal objection from your neighbour.
The 10 day rule keeps your project moving.
Deemed dissent is not the end of the road. Where an Adjoining Owner has not replied within 14 days, a further written request is served giving them 10 days to appoint a surveyor. This step is made under section 10(4) of the Act.
If they still do not appoint anyone within those 10 days, the Building Owner is entitled to appoint a surveyor on their behalf. That surveyor must still act impartially and protect the Adjoining Owner's interests, so the neighbour remains properly represented, but your project is no longer held up by inaction.
The practical point for Building Owners is this: a silent neighbour cannot block your build, but the formal Award route now applies, so allow time for it in your programme.
Speak to your neighbour first. It changes everything.
A legal notice landing on the doormat with no warning is intimidating, and a neighbour who feels blindsided is far more likely to dissent. A short conversation beforehand, showing the drawings and explaining why you are building, removes most of that reaction before it forms.
It is also the natural moment to cover the practical things people actually worry about: how long the works will take, what the working hours will be, where the skip and scaffolding will go, and who to contact if something concerns them.
This costs nothing, frequently turns a dissent into a consent, and protects a relationship that will outlast the build by many years.
Speak directly with a party wall surveyor in London. In one short call, we review your project, confirm which notices apply and tell you exactly what needs to happen next.
As your party wall surveyor in London, LENIO manages every stage of the notice process from initial review through to confirmed service on all affected Adjoining Owners.
We assess your drawings and proposed works against the Party Wall etc. Act 1996. This confirms whether notices are required, which sections apply and which Adjoining Owners must be notified before works begin.
We identify every neighbouring property owner whose property may be affected, using Land Registry checks where needed. Serving notice on every affected Adjoining Owner is a legal requirement and a common source of error.
We prepare the correct Party Wall Notice for each affected Adjoining Owner. Every notice is drafted to the full requirements of the Act, including the correct works description, intended start date and statutory statement.
We serve all prepared notices by a valid method and within the correct notice period for each section. For Section 3 works, two months' notice is required. For Section 1 and Section 6 works, one month's notice applies.
We follow up on every response and keep you informed throughout. If your neighbour consents, the process moves forward. If they dissent or do not reply, we manage the formal next steps under the Act, including the 10 day follow up request.
An invalid or incorrectly served Party Wall Notice can set the entire process back. If the notice does not meet the requirements of the Act, the full notice period must restart from the date a valid notice is served. On a project with a booked contractor, that delay has a direct cost.
Free online templates are widely available and they are lawful to use. The difficulty is that they are generic, so they often lack the technical precision the Act expects, particularly in the description of works and the identification of owners. On a straightforward job with a friendly neighbour they may be fine. Where the works are complex or relations are delicate, a professionally drafted notice removes the validity risk entirely.
In London, party wall notice requirements arise on most renovation projects. Terraced houses, semi-detached homes and converted flats mean that shared walls and close boundary lines are the norm, not the exception.
LENIO is led by a Chartered Civil Engineer and Member of the Institution of Civil Engineers (ICE), and a Chartered Building Engineer and Member of the Chartered Association of Building Engineers (CABE). A chartered surveyor leads every instruction personally.
Useful official guidance: the GOV.UK party walls guide and the GOV.UK explanatory booklet, which includes example notice templates.
See also our Building Owner's Surveyor service, our party wall services in London, or find your local London area.
LENIO prepares and serves party wall notices across London, backed by two chartered professional memberships.
The Institution of Civil Engineers (ICE)
The Chartered Association of Building Engineers (CABE)We prepare and serve Party Wall Notices for Building Owners right across the capital.
Whether your project is at the planning stage or your contractor is already booked, the right first step is to confirm which notices apply. LENIO provides free initial advice to Building Owners across London on party wall notice requirements. There is no obligation.
Note: This page is general guidance only and does not constitute legal advice. Party wall matters are subject to the specific circumstances of each project. LENIO recommends seeking professional advice before taking any formal steps under the Party Wall etc. Act 1996.
