Damp stains and leakage in a newly built house

2 Jan 2023
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United Kingdom
Hi there,

Since we moved in to a newly built house we noticed annoying damp stains, patches and the paint crumbling in a living room floor are - you can see it from the staircase. We've been trying to establish the potential cause of the issue and we failed. Had a plumber testing our boiler and underfloor heating - nothing was found. Leakage detection company could not find anything odd. A couple of days ago, we noticed an actual leakage with the water dripping down the ceiling in our basement level. It also started leaking from the floor connected with the staircase. We're starting an insurance claim. An emergency plumber cut holes in the ceiling to access and be able to view the issue. He could not locate the exact location of the leakage and advised to turn off the water supply in order to dry the area and to be able to return and investigate further.
We turned off the water supply just before the new year (31.12.2022) - we were hoping that the leakage would stop completely after no water is circling around the house. The leakage calmed down. On 01/01/2022 we came back home at 9pm and we have noticed a much worse water leakage from the same spots. To add, on both occasions there was a rainfall present. Right now, we woke up to a good weather with no rain and the leakage is much slower than it was yesterday. We have an internal drainage system and the roof is a hipped sedum roof with a small skylight at the top. I'm inserting some images of the ceiling in the basement level. I'm a bit
baffled as to why there seem to be two holes up the concrete - the insert seems to be white PVC pipe of some sort. We're desperately trying to find the answer - is it the plumbing issue or the roof is letting water in. The fourth image shows the small study room, above our bathroom. The last image shows the initial area of our concern when we moved in. There are some white sticky sheets covering the floor, suggesting the builder tried to cover it up.

I would really appreciate any form of input.



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Have you reported this to the builders? They have to be your first port of call unless you want to pay all the repair costs yourself.
Your pics are a bit too close, difficult to determine the context but the internal drainage arrangements for the roof have to be suspect, the heating system is also on the list (there will be a goodly volume of water in there even if the supply is off)
Thank you for your response! We're trying to get a response from the vendor in regards to all the issues, but they don't seem to be responsive. The house is covered under the new home warranty, however this only includes structural damage. In order to push my claim through, I will need to know specific cause of the damage. For now, the weather related issue with the actual water dripping down can be claimed under building insurance, I would have thought.
We will start investigating the internal drainage and perhaps book another inspection of the underfloor heating system of the whole house.
Your house will have come with a warranty, e.g NHBC - That is your primary port of call with something as significant as this. Get your paperwork out and familiarise yourself with all the relative information and who you need to talk to

If the builder/developer/vendor isn't responding then it's time to write a letter and send it recorded delivery and state that they have 7 days to respond to it before legal action. Go and talk to Citizens Advice too as to how to construct that letter in a legal framework. Time to get the gloves off before that gets any worse.
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YOU HAVE TO CHASE THE BUILDER- if you've made best efforts to notify them by email and have kept those timestamped messages they'll stand you in good stead.
Your buildings insurance may cover the repairs initially but all insurers require you to mitigate your losses- IE if you could have claimed against the builder/NHBC but didn't then you'll be repaying them.
Your house is defective- 'since you moved in'- are we talking days, weeks, months? Have you reported these defects to anyone?
EDIT @Madrab as always gives good advice, if the builder/warranty provider are being slow to respond then it is appropriate with significant water ingress to call in emergency repairs, your building insurers can subsequently chase the builders but it's really important to keep evidence of when you said what to who (emails and texts are good, phonecalls less good unless you can record them).
We moved in early December.

We asked our solicitors to send emails to the other side, asking for them to address the issues or put us in touch with the actual builder. I spoke to the new home warranty company before Christmas and they told me that in order to put my claim through, I need to specify (provide evidence) that the damage is caused by the structural issues, rather than underfloor heating or plumbing in general. I've also sent messages to the estate agent, who has their contact details.

I will have a meeting with my lawyer that can help me send letters to the vendor and start a legal case against them.
This is all good, were these communications in writing or just on the phone?
Re the warranty company (a) was this in writing (b) you've reported the problem to them, they've come back with some nonsense, continue your 2 pronged attack (getting an urgent problem sorted via your building insurance cover this mitigating liability, put vendor and warranty cover bunch on notice). Make sure any trades sent round by building insurer are aware that this squabble exists, they need to thoroughly evidence any work they do (pictures of before and after is the main one)
So, the solicitors sent them emails, I sent Whatsapp messages to the estate agent and I have also emailed the vendor's solicitors directly today again. I have an email from the warranty company saying that if I think the nature of the damage is considered to be covered under warranty, then I have to present some evidence (survey, inspection report etc.). I then had a phone call with the claims guy after I had some professionals testing the house and he told me that it is my responsibility to present the evidence, otherwise the claim might be rejected with not enough evidence to put through to their insurer. So far we haven't been able to come up with the exact reason that would be connected to structural issues. However, just now, we had a visit from a builder that does drainage etc. He told us the house drainage system has not been designed properly and this can let the water inside through the walls, some small cracks, gaps in the seals when raining. He will have to do a full survey on the house, so we can present the full report to the warranty company. But, if he is right in what he is talking about, this is going to be a huge building job to make sure the drainage system is rebuilt and fit for the purpose to prevent any water ingress and remove the damage to the inside.

In the meantime, I am going to call the building insurance company once they re-open tomorrow and push my claim through. We will definitely keep on documenting everything related to the issue. Thank you very much for your responses, it's a very overwhelming experience, being a first time buyer and having to deal with some many issues in a newly built house.
The important this is to move this forward in a timely manner, make sure it's all in writing and sent registered signed for and give them 7 days to respond, that's key. Get written reports from any trades and any investigations or works performed must all be in writing from qualified trades in headed paper

If the responsible parties don't move this forward for you as requested in the timescales stated then you are clear to threaten to legally move against them.

Who holds the building warranty and have you read exactly how the cover works? I am surprised that they are not taking a more proactive approach. As they are telling you that you are totally responsible to have it all surveyed and investigated, then I'd make sure that is correct re the paperwork, that doesn't sound right.
All as @Madrab . Those weasel words from the warranty company are very wrong- as a lay person it is unreasonable of them to require you to provide evidence of 'structural issues'. A rational response (from them) would be to send some sort of surveyor/assessor out, if they are as shady as they sound they'll probably reject your evidence due to 'surveyor not having our required qualifications/not on our approved list ' (neither of which facts they'll bother to share with you up front).
Preserve everything, if you have legal cover with any of your household policies it might be wise to get them on the case- even cheap solicitors bill out at £200 per hour plus VAT
As @oldbutnotdead suggests, the builder is normally the correct place to start, as far as building/structural defects are concerned ( drainage/soil runs etc would be considered part of the building fabric) and they would be the first port of call. I believe that's the case right up until 2 years after taking ownership.

As far as you insurance company is concerned then it I really don't think it should be your responsibility to have to pay considerable costs for root and branch surveys etc that this investigation may require, unless they will guarantee reimbursement as part of the claim.
We have found a surveyor that specialises in the drainage and waterproofing and he will come in later this week and do a full survey. With his report, we can start a claim with them. He seems to be knowledgeable and said he knows our warranty company very well, as he's been dealing on behalf of his clients in terms of warranty issues etc. It's shame about having to spend money for getting all these trades and surveyors coming in to establish the issue with the house.

Tomorrow, I will start a claim with the building insurance and get someone in for another trace and access. For some reason, I still cannot rule out the possibility of the leakage from the underfloor heating, but everyone keeps on telling us the pressure is okay, otherwise it would drop down to zero and we had the living room area tested with a thermal camera - perhaps the water travelled from other part of the floor. The ceiling in the living room is soaking in water. I peeled off the paint so easily and the water was coming from underneath. The original leakage in the bathroom ceiling is alright, less drops of water. In other parts of the ceiling the paint has peeled off, however it doesn't seem to be soaked in water.

I'm still unsure about why would we have holes in the concrete floor - the inside of each hole looks like it's a pvc pipe. The ones on the attached photo is leaking the water. Some of the other ones are completely dry.


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