Build Over DrainAGE Surveys
Build over drain surveys to support build over and build near applications across Cheshire, Manchester and Staffordshire.
✔ Fast turnaround
✔ Clear, easy to understand reports
✔ Advanced CCTV technology
You may need a survey if you are:
Planning an extension over or near a sewer
Submitting a build over agreement application
Working with a builder or architect on a project
Asked by your local water authority for drainage inspection
A build over drain survey is required when you plan to build over or near a public sewer.
Water authorities require a CCTV inspection of the drainage system to assess its condition to support your build over agreement.
We carry out the survey and provide the reporting needed to support your application.
If you are planning to build over or near a drain, a CCTV drain survey is usually required by most water authorities as part of a build-over agreement. This is particularly important where public sewers or shared drainage systems are involved.
When Is a Build Over Survey Required?
A build over drain survey is typically needed when:
Building an extension - if your extension is being built over or close to a public sewer or shared drain, a build over agreement is usually required, with a CCTV drain survey needed to support the application.
Structural alterations - if carrying out work within the vicinity of or over a public sewer or shared drain
Projects affecting shared or public sewers - if you intend to reroute or divert a public sewer or drain, the water authority will need to be notified.
Before approval is granted, the condition of the drainage system must be assessed to ensure it can support the proposed works. Requirements vary by water authority but are generally required when building over or within 3 metres of a public sewer or shared drain.
The Risks of Not Carrying Out a Survey
Without a proper drain survey, your project may face delays or complications during approval.
Common risks include:
Rejected build-over applications
Delays in starting construction
Unexpected drainage issues discovered mid-project
Costly rework if problems are identified too late
In some cases, building without proper assessment can lead to compliance issues or damage to existing infrastructure.
How a Drain Survey Supports Your Project
A build over drainage survey provides a clear assessment of the drainage system before work begins.
It allows you to:
Confirm the condition of existing pipework
Support build-over applications with accurate data
Identify issues early and avoid disruption during construction
Progress your project with confidence
Carrying out a drain survey early in the planning process helps prevent delays and ensures your project remains compliant from the outset.
Failing to carry out a proper survey can lead to delays, rejected applications, or costly issues during construction if problems are discovered later.
How much does a build over drain survey cost?
A build over drain survey is typically slightly more detailed than a standard CCTV drain survey, as it’s used to support build over applications to your local water authority.
Typical build over drain survey costs:
Standard residential drain surveys start at £200 plus VAT, with cost increasing for larger properties.
Commercial drain surveys are dependant on the size and complexity of the system being inspected.
The exact cost depends on the size of the property, the complexity of the drainage system, and the level of reporting required.
What affects the cost of a drain survey?
Several factors can influence the price of a build over drain survey:
Property size: Larger homes and commercial sites often have more extensive drainage systems, which take longer to inspect.
Accessibility: If access points (manholes) are difficult to locate or require additional work, this can increase the time required on site.
Level of reporting required: Build over surveys often require more detailed documentation to support applications to water authorities.
What’s included in a build over drain survey?
A typical build over drain survey includes:
Full CCTV inspection of the drainage system
Identification of pipe condition and any defects
Assessment of whether the drain is suitable to build over or near
High definition footage and supporting images
A clear, structured report suitable for submission
We provide clear, practical reports designed to help move your project forward without delays.
Avoid delays and unexpected costs
Skipping a proper survey, or using a basic inspection can lead to:
Rejected build over applications
Unexpected drainage issues during construction
Costly delays and redesigns
A professional survey helps ensure everything is identified early, saving time and money.
Because every drainage system is different, the best way to get an accurate cost is to request a quote.
We provide:
Transparent pricing
Fast availability
Surveys designed to meet build over requirements
Contact us today for a quick, no-obligation quote.
What does a Build over Drain Survey include?
We use high-definition CCTV equipment to inspect your drainage system internally. This allows us to assess condition and suitability.
You receive:
A full WRc-approved drainage survey report
Complete condition assessment
Annotated drainage map
High definition CCTV footage and images
Clear identification of any issues
Information to support your build over application
Whether the drain or sewer is suitable for build over
Why choose Clearflow Surveys?
What will happen:
Book your survey at a convenient time
We carry out a CCTV inspection on site
We produce a clear, professional report suitable for submission with you build over agreement
We aim to keep the process simple and efficient so you get the information you need in a timely manner.
We pride ourselves in:
✔ Fast turnaround to support project timelines
✔ Clear reporting suitable for submission
✔ Modern CCTV inspection equipment
✔ Experience supporting build over applications
Past Projects
Examples of build over drain surveys carried out across Cheshire, Manchester and Staffordshire.
Build over drain survey in Stoke-on-Trent, Staffordshire.
Post-build drain survey in Mobberley, Cheshire
Helpful build over guidance
Frequently Asked Questions
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A build over survey is a CCTV inspection of the drainage system carried out before, during or after construction work near or over an existing shared drain or sewer. It records the condition of the pipes so there is a clear record of what they looked like before the work began.
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If your extension is being built near or over a public sewer, your water company will almost certainly require one as part of their build over agreement process. Even if it isn’t required, it protects you - it establishes a baseline so you can’t be held responsible for pre-existing damage if questions arise later.
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Your architect or structural engineer may already know, but if not, a drainage map from your water company will show the location of public sewers on or near your property. We can also advise based on what we find during the survey.
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We carry out the CCTV survey and provide you with the report you need. The build over agreement application itself is submitted to your water company - usually by your architect, builder or solicitor. We’ll make sure the report gives them everything they need to support that process.
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Ideally before construction begins, so there is a clear record of the drain’s condition before any work takes place. A post-construction survey is also often required to confirm no damage occurred during the build. We can carry out both.
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You receive a full WRc-approved CCTV drainage survey report including condition assessment, high definition footage and images, with clear recommendations. It’s formatted to meet the requirements your water company expect.
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The survey itself typically takes one to two hours on site. Your report will follow shortly after, so it won’t hold up your project timeline.
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If we find existing damage before construction starts, that’s actually useful - it means you’re not liable for it later. We’ll set out clearly what’s been found and recommend next steps so you can deal with it before work begins.
Areas we cover
We provide pre and post construction drainage surveys across:
Need a Build over drainage Survey?
Get the inspection and reporting you need to move your project forward.