Most people first hear about party wall notices when a builder mentions them, usually later in the process than would have been ideal.
The Party Wall etc. Act 1996 is a separate legal process from planning permission and from building regulations. You can have both of those in place and still be legally required to serve notice on your neighbour before you start. Getting it wrong can stop a project, so it’s worth understanding early.
This is a plain guide to when a notice is needed, how long it takes, and what happens next.
When you need to serve a notice
The Act covers three broad categories of work. If your project falls into any of them, notice is required.
Work to an existing party wall or structure. Cutting into a shared wall to insert a beam for a loft conversion, underpinning it, raising it, thickening it, removing a chimney breast, or rebuilding it. This is the most commonly triggered part of the Act and catches a great many ordinary loft conversions and extensions.
Building a new wall at or on the boundary. A new wall built astride the boundary line, or up against it.
Excavating near a neighbouring building. Digging within three metres of a neighbouring structure and to a lower depth than its foundations, or within six metres where the excavation cuts a line drawn at 45 degrees down from those foundations. Rear extension foundations and basement work frequently fall into this category.
It doesn’t matter how well you get on with your neighbours. The obligation is statutory, and it applies to the work rather than to the relationship.
The notice periods
These are fixed by the Act and cannot be shortened, so they need to be built into your programme rather than discovered halfway through it.
Two months for work to an existing party wall or party structure.
One month for a new wall at the boundary.
One month for excavation near a neighbouring building.
A notice remains valid for twelve months from the day it was served. If the work hasn’t started within that period, the notice lapses and you’ll need to serve again.
The practical consequence is simple: raise the party wall question at design stage, not once the builder is booked. Two months is a long time to lose.
What a notice has to contain
A notice must be in writing, and it must include the name and address of the building owner, the address of the property where the work will happen, a description of the proposed work, and the date on which it’s intended to start.
It’s usual to phrase the start date as “on or after” a given date, which gives some flexibility without invalidating the notice.
A notice has to be served on every adjoining owner. That includes freeholders and leaseholders with more than a year to run, so a single property can have more than one. Missing one of them is one of the more common reasons a notice fails.
How to serve it
By hand, keeping a dated record. By post. Or by email, but only where the adjoining owner has expressly agreed to accept service that way — that provision was introduced in 2016 and it doesn’t apply by default.
Keep proof either way. If a dispute develops later, being able to demonstrate what was served and when matters a great deal.
If the adjoining owner is absent or can’t be traced, the Act provides for alternatives, including addressing the notice to “the owner” and fixing it to a conspicuous part of the premises.
What happens next
Your neighbour has fourteen days to respond, and there are three possible outcomes.
They consent in writing. The simplest result. Keep the consent on file and you can proceed. Note that consent doesn’t remove your other obligations under the Act — you must still avoid unnecessary inconvenience and provide protection where it’s needed.
They dissent. Perfectly normal, and not necessarily hostile. Many adjoining owners dissent simply because they want the protection of a formal award recording the condition of their property before work starts.
They do nothing. Silence for fourteen days following a notice about work to a party structure or about adjacent excavation is treated by the Act as dissent. A dispute is deemed to have arisen whether anyone intended it or not.
Dissent, in either form, triggers the surveyor process.
The surveyor process and the award
Once a dispute is deemed to have arisen, surveyors must be appointed before work can lawfully begin.
Both owners can agree on a single agreed surveyor to act impartially for them both. This is usually quicker and less expensive, and where relations are reasonable it’s the sensible route.
Alternatively each owner appoints their own surveyor, and those two select a third surveyor who can be referred to if they fail to agree.
The surveyors then produce a party wall award. This is a binding document setting out what work may be done, how and when it may be carried out, what protective measures are required, and usually a record of the adjoining property’s condition beforehand so that any damage can be identified afterwards.
Either party may appeal an award to the county court within fourteen days of it being served. In practice, appeals are rare.
What it costs
The building owner — the person doing the work — normally pays the surveyors’ fees, on the principle that the work is being done for their benefit.
Costs vary with the complexity of the scheme and with whether one agreed surveyor is used or two. An agreed surveyor on a straightforward loft conversion is a considerably smaller exercise than two surveyors and a third on a basement excavation.
We’re happy to give you an indication of cost once we know what’s proposed.
What happens if you don’t serve notice
The Act itself contains no penalty for failing to serve. But that’s less reassuring than it sounds.
An adjoining owner who discovers unnotified work can apply to the court for an injunction to stop it, and courts do grant them. You also lose the protection the Act gives you: without an award, and without a record of the neighbouring property’s condition beforehand, you are exposed to any claim for damage that follows and you’ll have very little with which to defend it.
Serving notice properly protects you at least as much as it protects your neighbour.
A practical suggestion
Speak to your neighbour before the notice arrives.
A formal notice landing on the mat unannounced tends to be met with suspicion, and suspicion tends to be met with silence — which the Act counts as dissent. A short conversation beforehand, explaining what you’re planning and why the notice is a legal requirement rather than a threat, makes consent far more likely and can save both of you time and money.
How we can help
We’ve been dealing with party wall matters across Gloucestershire, Stroud and the Cotswolds for a long time, acting both for building owners planning work and for adjoining owners who’ve received a notice.
We can advise on whether your project is notifiable, prepare and serve the notices correctly, act as agreed surveyor where both parties are content with that, or act for one side where they’re not.
