How Do We Know if a 3m Notice is Needed?

by The Party Wall Surveyor


We own a semi detached property which we currently rent out.  Our plans have been approved so we have permission to extend – 120cm along the front, 300cm along the back, and to build over the garage.  We have served party wall act notices to our neighbours – 3m notice to both, line of junction notice to both, and party structure notice to the neighbour who has the adjoining garage as our work will affect her garage (I’ll call her Neighbour A).  The neighbour on the other side (to which we are adjoined as a semi – Neighbour B) has kicked up a fuss – she made a number of complaints against the plans and got the parish council involved but the plans still got passed with no issue.  We feel that her grounds for complaning were unreasonable, e.g. saying the work will pose a security threat etc.  She is clearly trying to make things difficult, and although we are keen to extend and live in the property, to some extent she is succeeding in putting us off.

My question is around the process which we will now need to follow and the costs involved.  We visited both neighbours before submitting the plans, and again when we took the notices round, as we are trying to be as open as possible.  Both were friendly and positive about the extension.  However, Neighbour B is proving to be rather two faced – being happy about things to our face, and then objecting through the official channels.  Having served notice, we have received a prompt response from Neighbour B who, contrary to the conversation we had with her, is not happy and is electing to employ her own surveyor.  She has also noted on the response notice to us that she intends to “use the surveyor she has retained since March” when we originally put the plans to her.  We are now trying to work out what to do next and would also like to get an idea of how much the process may cost us.

Firstly – in these kinds of circumstances, what level of surveyor costs would be involved if we employ a surveyor, and she employs a different one.  Also, can we ensure that we are not liable for the costs of any kind of fee she has already incurred, for advice she has already taken from her surveyor or for any kind of retainer she may have him on?  We also know that Neighbour B has been visiting Neighbour A, who was originally very happy for us to extend and move back next door, but Neighbour B is trying to put everything in a negative light – so if Neighbour A decides to employ a 3rd surveyor, is that then additional cost to us?

We would also like to understand the process from here – we have paid to have steel calculations done, and these are now with the building regs man – from our understanding, he will work out how deep the footings need to be.  My questions on this are how and when do we find out the decision on the depth of the footings – or can this only be once work commences, by which point we have effectively decided to proceed?  And would this be before or after Neighbour B’s surveyor costs start?  And if the footings are not of such a depth that the 3m notice is actually needed, can we then withdraw it, and remove the need for a surveyor to be employed for Neighbour B?


When I get quite long questions such as this I tend to pick out the most important points and respond to those rather than going through it line by line. Let me know if I have missed anything.

Upon receipt of your notice your neigbours gained the right to dissent and appoint a surveyor. They are each free to appoint separate surveyors and you would be responsible for the reasonable fees of those surveyors. I don’t know the full details of your work but Adjoining Owners’ surveyor’s fees for domestic extensions typically come in at between £800 and £1,200 plus VAT (London prices c.2010) depending upon the complexity of the matters in dispute. There may be some cost saving in the same surveyor acting for both of your neighbours so it may not be a bad thing that they are discussing the matter. The Act allows you to appoint the same surveyor as your neighbours (referred to as the ‘Agreed Surveyor’) although that would require your neighbours’ consent.

Regarding your 3 metre notice – you can withdraw it later if you find that your excavations do not come within the scope of the Act but the general view is that you would be responsible for the costs of dealing with that notice up until the point that it is withdrawn.


We don’t yet know if the footings will go as deep as to require the 3m notice, we were just covering ourselves, but perhaps we shouldn’t have served notice yet – we were just trying to do the right thing.  If we send a letter to the Neighbours to withdraw the notice now, to avoid unnecessary costs, can we serve notice again at a later stage if the footings go to a depth that requires it?

Also, are we liable for any costs for the Neighbour’s surveyor between March when she instructed him of her own accord and when we served notice i.e. 10th June?

Finally, as the Line of Junction notice does not require a response (the templates I used only have acknowledgement letters for the 3m and Party Structure notices) does that mean we can just go ahead, i.e. no surveyor needed even if the Neighbour wanted a surveyor for this?


You can withdraw and the re-serve the Section 6 notice later although if your neighbour wanted to be difficult they could hold you to the 1 month notice period on the new notice.

You are only liable for your neighbour’s surveyor’s costs from the time that you served the notice – if your neighbour has used a surveyor to advise them on planning matters that would be down to them. It will be up to your appointed surveyor to agree the other surveyor’s fees in accordance with Section 10 of the Act.

No response is required to a notice served under Section 1 if the new wall and its foundations are wholly on your land and you are not requesting to commence work early – you can start once the notice period runs.