If you’re extending or adding to your house at all you will always need to find out if there are pipes/sewers under or nearby your site.
If there are pipes within 3m of your proposal, you will need Thames Water approval.
First of all, try searching your property at https://www.thameswater-propertysearches.co.uk/ . Or... take a trip down to your local authority offices and have a look at their sewer maps.
These maps may not tell you exactly where and what the pipes are. So.......
We suggest getting the professionals in and paying for a CCTV drainage survey. Expect to pay only approx. £200 for this service.
TIP: This is also a great opportunity to check the condition of your sewer pipes, and could save you £££'s in project delays.
You need to fill out a Thames Water Build Over application form. Make sure you get your approval before you start laying your foundations to avoid fines or extra charges.
TIP: If using our services we can coordinate the relevant drawings needed and make the application on your behalf.
It shouldn’t take more than 21 days.
Your contact information
A cross sectional foundation plan (which can be provided by us or your Structural Engineer)
A drawing of the pipe/sewer locations relative to both your existing property and your proposed work.
A copy of the drawings you submitted for your ‘Building Regulations’ approval.
If you’re eligible for a self-certified agreement, all you need to do is fill out the online questionnaire and you may start your work immediately (providing your work complies with the description you gave in the online questionnaire).
A self-certified agreement is free of charge.
To find out whether or not you are eligible for a self-certified agreement, fill in the questionnaire on the Thames Water Build Over website (link above)
...or ask us!
It depends on the size of your sewer.
If your sewer diameter is no more than 160mm, the application will cost you £299 (presumed domestic property).
If your sewer diameter is higher than this (which is unlikely in a residential project) expect a slightly higher cost.
Ring us on 0203 189 1619
Email on: email@example.com
Or, click "START HERE" at the top of the page
The diagram below outlines the most frequent scenarios: