Rain Water Damage Via Broadband Duct

19 Sep 2011
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United Kingdom
We live in a new build (2015) and have recently discovered rainwater has been entering under the floor via the phoneline/broadband duct. The green box is at a higher elevation and the duct didn't have either sufficient drainage or wasn't sealed properly when the property was built meaning it filled up and then was able to escape into the house.

This has led to water trapped between the concrete base and insulation (actual flooring is fine and dry). The duct has recently been isolated but there remains the issue of potential damp from water that is still there (there's a few holes cut in the floor so I can see that the concrete is still damp to the touch as are some timbers). The only solution I can think of is to take up all the flooring, get some industrial dehumidifiers and run them until it dries out - not ideal and expensive.

NHBC have rejected the claim as it doesn't fall within their policy as the issue isn't caused by a structural defect. My own insurance says it falls under accidental damage which I don't have on my policy - but I don't see this as accidental damage this is a fundamental issue with the development of the house not due to some accident cause by us or otherwise.

My question is - who should ultimately be responsible for rectifying this type of issue? Given that:

- the source of water is rainwater
- the ingress point was in a duct external to the boundary of the property
- the duct design came from BT/Openreach but was installed by a subcontractor to the builder (large national company)

It seems like no one wants to take responsibility and leaves us with damaged property and an extremely expensive problem to fix.

Appreciate any advice - the builder said that this has occurred on other developments in the past and has lead to BT changing the design of the ducts as a result.
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I that this would be construed as a design defect and therefore something that the builder is liable for, irrespective of time elapsed. Your claim should be against the builder and then they would claim against BT.

However, getting them to accept this will be difficult.
the builder said that this has occurred on other developments in the past and has lead to BT changing the design of the ducts as a result.

If you can get him/her to put that in writing along with other examples then I would have thought it would help BT accept responsibility.

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