Do you need approval?

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If you’re planning to improve your home by extending it, or adding a conservatory, annex or garage, you’ll need to know if there’s drainage on your land. If there’s pipework near where you’re planning to build, it could affect the design of the building.

It's best to know where the pipes are when you're planning your work, to help avoid delays and additional cost. Don't worry if you're not sure how to do this - we're here to help.

Your building works

When planning your building works, you’ll need to check whether there are pipes nearby. If so, you might need our approval before work begins.

Please see page 4 of our guidance or check here for details on how to find out if a sewer appears on a map of public sewers. You can also find out more about our process in Getting approval.

To check whether you need our approval, there are two things you need to do:

If you’re building within three metres of a public sewer, or within one metre of a public lateral drain, you’ll need our approval before work begins.

Applying for permission is simple using our self-certification questionnaire. If you qualify, there’s nothing to pay. If you aren’t able to self-certify, you need to apply for an approved build over agreement and may qualify for a discount if you do it online. Alternatively, you can print and manually fill out the PDF application form.

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If you’re not building within three metres of a public sewer, or within one metre of a public lateral drain, you won't need our approval to continue with works.

If you'd like confirmation in writing, email us a scaled ground floor plan of your property, showing your planned work and the complete sewer layout. We’ll then check your plans and confirm that approval isn’t needed.