How important is a party wall when it comes to semi-detached rear extensions?

If you live in a semi-detached house and are thinking of undergoing building work, it's worth considering what effect the work will have on neighbouring properties. For some projects, you could be faced with the Party Wall Act. After all, any problems your proposed extension could cause for your neighbours could very quickly become yours! This is largely due to the mysterious ‘Party Wall’ that so many home renovators have lost sleep over. We break down what they are, why they matter and what they could mean for your renovation – not to mention your relationship with your neighbours.

First off, what’s a party wall?

Party walls act as a kind of buffer between terraced houses, semi-detached houses and some detached houses – these can be a literal wall, an outhouse or an unseen boundary that you share with a neighbouring property.

If your project affects a party wall or you plan on excavating within 3 to 6 metres (depending on the depth of the new foundations) of your neighbour’s property, then you need to obtain permission from the affected households at least 2 months before any construction occurs. Due to the intimate nature of semi-detached properties, it’s really important to make sure each step is followed accurately.

So, if you’re planning on extending your semi-detached home, it’s best to check with your neighbours first. If you don’t, you may have to pay for their property damage and legal costs if they take you to court. To avoid this situation altogether, it's worth getting a surveyor out to check the property line and speak with them about how far they think you'd be able to extend before coming into contact with any neighbouring properties.

Find out what steps you might need to take with a free advice call with one of our consultants.

What happens if your neighbour refuses permission?

Your neighbour can reject your project in one of two ways: they can refuse outright or simply not respond to your notice within those first 14 days. If a response isn’t given, a 10 day follow up letter will be sent. If this isn’t responded to either, then you’re legally required to seek a ‘party wall agreement’ in order to obtain the necessary permission.

Are party wall agreements the answer for semi-detached houses?

If you live in a semi-detached property, it’s quite likely that you share a party wall with your neighbour. If you’re planning to make changes to the party wall, the adjoining property owner will have a say in what happens. So, whether you’re thinking about adding an extension or changing the appearance of your property by installing new windows, it’s vital that you obtain consent from anyone that owns the property next door. This can be achieved with a party wall notice.

How do you serve a party wall notice?

A party wall notice can be served by either a party wall surveyor (typically for a flat fee) or yourself – you can find the necessary forms here. A letter of acknowledgement for the neighbour to complete and return is usually included. This ensures that all those affected by the project are properly informed. We recommend not serving the papers yourself to avoid any avoidable mistakes that could halt construction.

If one owner doesn’t want any work to go ahead or if they simply object strongly enough, they may still be able to stop any construction occurring as long as they can prove that there would be significant damage caused by doing so but serving a party wall notice reduces this risk. Usually, party wall disputes are resolved with a party wall agreement covering:

• A “schedule of condition”; basically a record of the adjoining properties condition prior to works starting, so in the event of a dispute over areas affected by the construction, this document, complete with photographs, provides clear evidence.
• What the project intends to create, supported by architectural drawings.
• How the proposed works will be carried out by the building party.

Most party wall disputes are resolved and calm is restored but for any rocky moments along the way, we’re here to help shine a light on best practices for resolution. For more insight, speak to one of our expert consultants or learn more about party walls here.