Hello Everyone 

 

I am planning for a garage conversion to a habitable room and my building control provider sent a consultation to Thames water and they reverted that I may need a build over agreement. I have attached my drainage search report (property marked in black) and I notice there is a combined sewer running within the property and which is for my use only. It gets connected to a public sewer which is more than 3M away and I already have a garage which sits on this combined sewer which is getting converted.

 

would I need a agreement in the first place for this conversion ?

 

Edited February 10, 20251 yr by Neoc
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If you are not building any new walls or foundations this should not apply.  Changing use will not affect the integrity of the drains!

Thanks. I have the garage door where a new window will come up, that’s the only “extra” I am building. 
 

as the sewer is in my property and 3 mts away from the public sewer, does it still apply ?

I do not think a build over agreement will apply.

How do I take this up with Thames water, I have written ti them already but checking if there is any other way.

Mr P is rarely wrong 

Push on 

Thanks for the assurance, will keep pushing 

Thames Water used to check sewers on individual properties when an application was made. LA's and private BCO's then started sending every application to them for checking (I can't recall what prompted that) Thames Water responded by sending back a standard response saying you may need a build over agreement, basically putting the onus on you to check as obviously they didn't have (or want to use) the resources to look at each and every one.

 

Your drain is private until it leaves your property when it become a public lateral drain before joining the public sewer proper. Your works appear to be at least 3 metres from the public sewer (the red line) and at least 1 metre from the point where your private drain becomes a public lateral drain at you boundary. You don't therefore need a build over agreement.

Thank you everyone for the guidance. I pushed back and they have confirmed that the build over agreement is not required.

 

My contention was the following in case it helps others:

 

I am not changing the structure of the garage and it’s a conversion and no new build.

 

the sewer is more than 3 mts away from the structure hence it falls outside of the build over agreement prerequisites.

 

Thanks once again and I am relieved !