Build-over support · UK-wide

Build near drainage.
Plan it properly.

Design and technical support for extensions and structures proposed close to or over public sewers, coordinated around the relevant water authority requirements.

Protect access and structure

Drainage constraints need to shape the design before construction begins.

Building close to a public sewer can affect foundations, access and the approval route. We review the proposed work against the available drainage information and develop proportionate technical details for the agreed scope.

Early coordination helps avoid a layout or foundation solution that conflicts with the sewer position, depth or authority requirements.

Drainage review
Foundation coordination
Clear drawings
Authority-ready information
What we provide

Technical support for build-over applications

The required information depends on the sewer, proposed work and relevant water authority.

01

Drainage Information Review

Review of available sewer records, site information and proposed building position.

02

Build-Over Drawings

Plans and sections showing the relationship between the proposal and affected drainage.

03

Foundation Design

Proportionate foundation details developed around sewer position and depth.

04

Protection Details

Relevant bridging, clearance or protection principles for the agreed design.

05

Application Support

Preparation of agreed technical information for the authority process.

06

Design Coordination

Alignment between architectural layout, drainage constraints and structural requirements.

Your project package

Clear information around the sewer and structure

The package is matched to the authority requirements and the information available.

A

Location information

Plans identifying the proposed work and relevant drainage route.

B

Relationship sections

Sections showing foundation depth, clearances and sewer position.

C

Structural details

Foundation or bridging information for the agreed design solution.

D

Supporting notes

Clear technical notes describing assumptions and proposed protection.

Simple process

Four clear steps from enquiry to delivery

01

Share the proposal

Send the site address, drawings and any drainage records or survey information.

02

Review the sewer

The available position, depth and relationship to the work are assessed.

03

Coordinate the design

Layout and foundations are developed around the identified constraints.

04

Issue information

The agreed drawings and technical details are prepared for the application route.

Common questions

Build Over Agreement, clearly explained

Straight answers about scope, information and project delivery.

What is a Build Over Agreement?

It is an agreement with the relevant water authority for qualifying building work over or close to a public sewer.

How do I know whether a sewer is public?

Drainage records and site information should be reviewed. Ownership and authority requirements depend on the specific drainage arrangement.

Can foundations cross a sewer?

The acceptable solution depends on sewer position, depth, condition and authority requirements. The design must be reviewed case by case.

Do you submit the application?

Application support can be included where expressly agreed, using the drawings and information available for the project.

Should this be resolved before construction?

Yes. The drainage relationship and required authority route should be established before affected foundations or building work begin.

Building near a public sewer or drainage route?

Share the drawings and drainage information for a coordinated technical response.