Can My Neighbour Stop My Extension? (UK Law Explained)

A neighbour cannot stop a lawful extension simply because they dislike it, but they can intervene in several specific circumstances. The first point of intervention is usually the planning stage. When you submit a planning application, your neighbour has the legal right to submit an objection. However, councils only consider objections that are based on valid planning grounds. These include issues such as loss of natural light, overshadowing, loss of privacy, an extension appearing overbearing, concerns about the structural impact on their home, or a design that is completely out of character with the surrounding area. Personal preferences or emotional objections carry no weight — planning officers are only interested in factors that fall within national and local planning policy.

The second stage where a neighbour may intervene is under the Party Wall etc. Act 1996. Many extensions involve work that activates the Act, especially in densely built areas where homes sit close together. If the project requires excavation within three or six metres of the neighbouring foundations, cutting into a shared wall, building directly on the boundary line, or removing features like a chimney breast connected to the party wall, you must serve the correct Party Wall Notices before work begins. If you fail to serve notice, your neighbour can apply to the County Court for an immediate injunction, stopping all building work — and you may also be required to pay their associated legal costs.

Once the correct notices are served, your neighbour has a choice in how to respond. They can give written consent, decline the notice and appoint their own surveyor, or choose to use the same surveyor as you. If they dissent, the surveyor(s) will produce a legally binding Party Wall Award that sets out how the work must be carried out to protect both properties. While the Act cannot be used to block an extension entirely, it can delay the start of the project until this Award is completed and agreed.

A third situation where a neighbour may intervene is if the extension risks damaging their property. If they believe the works are unsafe or may cause structural harm, they can contact building control, raise concerns with a Party Wall Surveyor, or pursue compensation if genuine damage occurs. This is one of the key reasons why a Party Wall Award is so important: it records the condition of the neighbouring property before work begins and sets out safeguards to minimise risk. If damage does happen, the Award provides the mechanism for resolving the issue fairly.

What If the Neighbour Refuses Access?

One issue that often arises during extension works is access. If your project requires you to enter your neighbour’s land — for example, to put up scaffolding, carry out repairs, dig foundations, carry out a survey or complete waterproofing — the law does provide a right of access. Under the Party Wall etc. Act 1996, a neighbour cannot simply refuse access without a valid reason. However, they can delay things until the correct notices and procedures have been followed. In other words, access isn’t automatic: you must follow the legal steps first, and only then does it become unreasonable for them to object.

Can a Neighbour Stop You Using Permitted Development Rights?

If your extension falls within the rules for permitted development, you don’t need planning permission and your neighbour has no authority to block it, even if they strongly object. The council also cannot refuse a permitted development extension simply because a neighbour complains. The only thing to bear in mind is that permitted development has nothing to do with the Party Wall Act — so even if planning permission isn’t required, you may still need to serve Party Wall notices if the work affects a shared wall or involves excavation near the boundary.

How to Prevent Neighbour Problems Before Starting Your Project

Most disputes and delays can be avoided with simple preparation. Speaking to your neighbour early, showing them your drawings and being open about your plans goes a long way. Serving the correct Party Wall notices and using a professional surveyor gives both sides confidence, and keeping your neighbour informed removes the sense of being “kept in the dark,” which is where many tensions begin. A little communication usually prevents 90% of problems.

When to Involve a Party Wall Surveyor

There are, however, situations where involving a Party Wall Surveyor is not just helpful but essential. If your work involves digging near the boundary, altering a shared wall, or if your neighbour is already displaying uncooperative behaviour, a surveyor safeguards you. They document the neighbour’s property condition before work begins, ensure the works are legally compliant and create a Party Wall Award that protects you if any false damage claims appear later. It is essentially a safety net for both parties.

Can a Neighbour Stop an Extension by Ignoring Party Wall Notices?

Some homeowners worry that a neighbour can stop the entire project simply by ignoring a Party Wall notice. This isn’t the case. If there is no reply within fourteen days, the law treats the silence as a disagreement, and a surveyor is appointed on the neighbour’s behalf. The process then continues in exactly the same way as if they had actively dissented. Once the Party Wall Award is finalised, you are legally free to begin work. Their silence cannot block the extension.

In summary, neighbours do have certain rights: they can raise planning objections, slow the process by appointing their own surveyor, request adjustments to protect their property, apply for compensation if genuine damage occurs and, if you begin work unlawfully, they can even seek an injunction to stop you. But there are equally clear limits. They cannot prevent a lawful extension from being built, cannot block permitted development, cannot refuse reasonable access when the law requires it and cannot use the Act as a weapon simply because they dislike your plans. When procedures are followed correctly, the extension will go ahead — with or without their cooperation.

Need Help With a Party Wall Notice or Dispute?

If your neighbour is being difficult — or you’re starting an extension and want to avoid delays — we can manage the entire Party Wall process for you.

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