Build Over Agreements

If you are building over or close to a public sewer, you may need a build over agreement with your regional water authority. This is often the case with rear and side extensions when sewers are present.

A build-over agreement is a formal legal contract between you and Severn Trent. It is required if you are planning to build an extension or a new structure over or close to (usually within 3 metres of) a public sewer or lateral drain to protect the pipes and ensure ongoing maintenance access to the inspection chamber.

Sometimes it is necessary to use a specialist foundation where public sewers are present. Extension Drawing Services have plenty of experience working with these types of footings in both design and building capacities - vital knowledge if these pipes are present at your property.

If the drains aren’t too deep on many occasions normal footings can be used. Even so, build-over agreements are required. This is a well-trodden path for us, and something we assist with after planning approval. This work often forms part of the building regulations package, especially where footing design is required.

Extension Drawings Services can take care of this build over agreement for a fixed fee.

Why It Matters

Structural Safety: Prevents the heavy weight of a new extension from cracking or collapsing underground pipes. Guarantees Severn Trent can still reach the network to clear blockages or repair damage. Conveyancers and buyers will ask for the sign-off letter; lacking a certificate can delay or block selling your home.

Once a professional surveyor is appointed, we work with them to provide architectural foundation drawings to your regional water provider, usually Severn Trent.