Planning out your home extension

One of the most common projects we undertake is an extension to a home or property. This could be the form of a very minor single storey rear extension or a complete remodelling of an existing property, almost unrecognisable from its original form.

As with all our projects we start with your brief of what extra space you want to create and then we look at how this can be integrated into the existing property and its function. Other important things to consider are the look of the extension and whether it is to appear as part of the original house in terms of its architectural style or we can offer something completely different.

How Much Will It Cost?

For a straightforward extension you should allow around £1,200–1,600/m² and upwards of £2000/m² for a high end specification. There are other factors to consider such as whether there are any nearby trees as these may have an impact on your foundation type and depth. If there are any public sewers running under or nearby your proposed extension approval may be required from the statutory service authority which can add to your build cost.

Will I Require Planning Permission?

Not all extensions require planning permission. Please visit our planning page to find out more about whether an extension requires planning permission or contact us and we will be happy to offer a free initial consultation.

Building Regulation Approval

Regardless of whether your new extension does or does not require planning permission, it will need Building Regulations approval. Please refer to our Building Regulation page for more information.

The Party Wall Act

Some extensions require you to notify your neighbours’ of your intentions to extend under the Party Wall Act. The Party Wall Act 1996 allows you to carry out work on, or up to, your neighbours’ land and buildings, formalising the arrange­ments while also protecting everyone’s inter­ests. This is not a matter covered by planning or building control.

Your neighbours cannot stop you from build­ing up to, or even on, the boundary between your properties, even if it requires access onto their land (providing you have planning permission to do so, and there are no restrictive covenants).

If your extension involves building or digging foundations within 3m of the boundary, party wall or party wall struc­ture, or digging foun­dations within 6m of a boundary, the work will require you to comply with the Party Wall Act. In these cases you may need a surveyor to act on your behalf.

Where your neighbour is in agreement to the work and don’t require a survey to be carried out then we can normally deal with a Party Wall Agreement on your behalf.

Extensions testimonials

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