Flooded house! Am I being cynical?
Discussion
Last weekend we unfortunately had a leak that resulted in the downstairs being flooded.
The kitchen and hallway are Lino which held the water but the lounge and study which were carpet were damaged resulting in the carpet coming out. We have had a dehumidifier running all week.
The insurance appointed drying team came out on Friday who immediately told me that injection drying would be the only solution. This involves drilling holes through the concrete floor into the insulation below to allow warm air to be blown into the wet insulation. This, he says could take 2-3 weeks or more.
This is obviously drastic. The moisture readings he took ranged from 3-4 on his meter. I don’t know what they meant but he said he wanted a reading of 2.5 before he’d sign it off as dry. The wall are all good as he put it.
He dismissed the dehumidifier and said I might as well turn it off as the insulation would never dry with the dehumidifier running.
My question is, is he correct? Nobody else has been to look at it and I don’t want to do him a disservice but he’s appointed by the insurance company directly, is he suggesting the best course of action for our property or his business? If I’m being grossly unfair, I’ll gladly hold my hands up and apologise but is it at all possible that there is another approach which could be investigated before embarking on such a major undertaking?
The kitchen and hallway are Lino which held the water but the lounge and study which were carpet were damaged resulting in the carpet coming out. We have had a dehumidifier running all week.
The insurance appointed drying team came out on Friday who immediately told me that injection drying would be the only solution. This involves drilling holes through the concrete floor into the insulation below to allow warm air to be blown into the wet insulation. This, he says could take 2-3 weeks or more.
This is obviously drastic. The moisture readings he took ranged from 3-4 on his meter. I don’t know what they meant but he said he wanted a reading of 2.5 before he’d sign it off as dry. The wall are all good as he put it.
He dismissed the dehumidifier and said I might as well turn it off as the insulation would never dry with the dehumidifier running.
My question is, is he correct? Nobody else has been to look at it and I don’t want to do him a disservice but he’s appointed by the insurance company directly, is he suggesting the best course of action for our property or his business? If I’m being grossly unfair, I’ll gladly hold my hands up and apologise but is it at all possible that there is another approach which could be investigated before embarking on such a major undertaking?
I don't know but interested to see how you get on. The diameter and spacing of the holes will be critical. Trying to dry out closed cell insulation will not be easy. I wonder how he will be able to tell when it is dry mid-way between the holes. I suppose that the alternative is to dig up the whole floor so this is worth a go. Sorry that you're having to go through this experience.
If it's closed cell insulation whether PU or EPS then exactly how wet is it going to be? The stuff is waterproof. Not exactly known for responding much to air ventilation either.
Screed and concrete aren't hugely permeable, they could be saturated but water won't have flowed through too far. The hydraulic pressure from the flooding wasn't high and I assume neither was the duration..
It'll dry out anyway just like it did when it was first installed. Which a dehumidifier will accelerate because why wouldnt it?!
All sounds like one of those snake oil things from here, pointless makework that seems to bear little relation to either the materials or how they usually lose moisture.
Screed and concrete aren't hugely permeable, they could be saturated but water won't have flowed through too far. The hydraulic pressure from the flooding wasn't high and I assume neither was the duration..
It'll dry out anyway just like it did when it was first installed. Which a dehumidifier will accelerate because why wouldnt it?!
All sounds like one of those snake oil things from here, pointless makework that seems to bear little relation to either the materials or how they usually lose moisture.
Would be worth knowing the construction, certainly if someone suggested drilling holes in it. Could be block & beam, might not.
But when I see a quote like the below...
Maybe if there were hollow blocks or something and it needed help i could see it, but usually the moisture will either be below the DPM in which case who cares (and if it got there and could come back there's bigger issues) or it's above in which case it'll leave on its own eventually and a dehumidifier would accelerate it.
But coming back to the insulation it might be vapour permeable but it's solid insulation, inevitably closed cell and doesn't hold water because there's nowhere for it to go. For similar reasons injecting air into closed cell insulation and concrete won't do much because it's basically solid, unless it leaks along the interfaces.
I can see a lot of people have bought the kit they'd be using and offer the service, but that's also true of lots of other magic solutions that are mostly misapplied. Bit like DPC injection has been.
Guess there's more money in doing setup work + hiring out special kit than in just leaving a dehumidifier sitting & working.
But when I see a quote like the below...
24lemons said:
He dismissed the dehumidifier and said I might as well turn it off as the insulation would never dry with the dehumidifier running.
My question is, is he correct?
I'd seriously wonder what they know. A dehumidifier will always dry it even if not the fastest option. If the moisture got in then it will come out again. And if the walls are dry there's a limit to how wet it could be as it just never got that wet in the first place. My question is, is he correct?
Maybe if there were hollow blocks or something and it needed help i could see it, but usually the moisture will either be below the DPM in which case who cares (and if it got there and could come back there's bigger issues) or it's above in which case it'll leave on its own eventually and a dehumidifier would accelerate it.
But coming back to the insulation it might be vapour permeable but it's solid insulation, inevitably closed cell and doesn't hold water because there's nowhere for it to go. For similar reasons injecting air into closed cell insulation and concrete won't do much because it's basically solid, unless it leaks along the interfaces.
I can see a lot of people have bought the kit they'd be using and offer the service, but that's also true of lots of other magic solutions that are mostly misapplied. Bit like DPC injection has been.
Guess there's more money in doing setup work + hiring out special kit than in just leaving a dehumidifier sitting & working.
I'd be astonished if insulation in a concrete slab had any significant moisture in it at all unless the laying was defective in the first instance, as others have noted concrete is practically impermeable. Unless there was standing water in the house for days how is water to be driven in there?
We can only speculate how the house is built and where water will have got.
Some houses are a chipboard floor over a layer of insulation like polystyrene foam.
That would be challenging to dry out with a dehumidifier.
If it's a concrete floor then drilling into it at random will potentially risk going through the damp proof membrane.
What relative humidity is the dehumidifier achieving? How much water a day is it making?
It may not being drying the floor as such, but it might be helping keep the rest of the house tolerably dry or less wet.
OTOH, depending on the weather you might do better to just open the windows.
Somebody who knows the construction details is better placed to suggest cures than random amateurs on the interweb.
Some houses are a chipboard floor over a layer of insulation like polystyrene foam.
That would be challenging to dry out with a dehumidifier.
If it's a concrete floor then drilling into it at random will potentially risk going through the damp proof membrane.
What relative humidity is the dehumidifier achieving? How much water a day is it making?
It may not being drying the floor as such, but it might be helping keep the rest of the house tolerably dry or less wet.
OTOH, depending on the weather you might do better to just open the windows.
Somebody who knows the construction details is better placed to suggest cures than random amateurs on the interweb.
https://servicemasterrestore.co.uk/target-drying-e...
Never heard of it before. Makes perfect sense for suspended floors etc but like other is really don't see what it will do on a concrete floor.
The above link makes the same claims.
We have just built our house. The stuff is all stored outside for starters.
The first slab is poured and that is in the weather for moths and often rained on. Then you have the dpc / closed cell insulation and the next layer. Then on top of that underfloor heating and screed.
I cannot see how ( a) the insulation can get saturated and ( b) how there blowers can move air behind it.
You are right to be sceptical. I would have though the real damage would be skirtings and the bottom of the dry wall
Never heard of it before. Makes perfect sense for suspended floors etc but like other is really don't see what it will do on a concrete floor.
The above link makes the same claims.
We have just built our house. The stuff is all stored outside for starters.
The first slab is poured and that is in the weather for moths and often rained on. Then you have the dpc / closed cell insulation and the next layer. Then on top of that underfloor heating and screed.
I cannot see how ( a) the insulation can get saturated and ( b) how there blowers can move air behind it.
You are right to be sceptical. I would have though the real damage would be skirtings and the bottom of the dry wall
For the reasons already given, I don’t buy the drilling thing if it’s concrete slab/PIR.
Is it a proper sized dehumidifier or a consumer one?
We have several commercial ones (that pump out via a hose instead of having a small tank) and they can pull a fair amount of water out of the air. I’d be getting something like that in place and getting he heating turned on/up (warm air holds more water so helps the dehumidifier).
Is it a proper sized dehumidifier or a consumer one?
We have several commercial ones (that pump out via a hose instead of having a small tank) and they can pull a fair amount of water out of the air. I’d be getting something like that in place and getting he heating turned on/up (warm air holds more water so helps the dehumidifier).
Jeremy-75qq8 said:
No scale on their graph…JoshSm said:
Would be worth knowing the construction, certainly if someone suggested drilling holes in it. Could be block & beam, might not.
But when I see a quote like the below...
Maybe if there were hollow blocks or something and it needed help i could see it, but usually the moisture will either be below the DPM in which case who cares (and if it got there and could come back there's bigger issues) or it's above in which case it'll leave on its own eventually and a dehumidifier would accelerate it.
But coming back to the insulation it might be vapour permeable but it's solid insulation, inevitably closed cell and doesn't hold water because there's nowhere for it to go. For similar reasons injecting air into closed cell insulation and concrete won't do much because it's basically solid, unless it leaks along the interfaces.
I can see a lot of people have bought the kit they'd be using and offer the service, but that's also true of lots of other magic solutions that are mostly misapplied. Bit like DPC injection has been.
Guess there's more money in doing setup work + hiring out special kit than in just leaving a dehumidifier sitting & working.
If you think about it a dehumidifier removes water from air ONLY. Hence the comments of the team. I would turn the heating up and use the dehumidifier unit until the humidity is down to 50%. No idea about the blowing air stuff.But when I see a quote like the below...
24lemons said:
He dismissed the dehumidifier and said I might as well turn it off as the insulation would never dry with the dehumidifier running.
My question is, is he correct?
I'd seriously wonder what they know. A dehumidifier will always dry it even if not the fastest option. If the moisture got in then it will come out again. And if the walls are dry there's a limit to how wet it could be as it just never got that wet in the first place. My question is, is he correct?
Maybe if there were hollow blocks or something and it needed help i could see it, but usually the moisture will either be below the DPM in which case who cares (and if it got there and could come back there's bigger issues) or it's above in which case it'll leave on its own eventually and a dehumidifier would accelerate it.
But coming back to the insulation it might be vapour permeable but it's solid insulation, inevitably closed cell and doesn't hold water because there's nowhere for it to go. For similar reasons injecting air into closed cell insulation and concrete won't do much because it's basically solid, unless it leaks along the interfaces.
I can see a lot of people have bought the kit they'd be using and offer the service, but that's also true of lots of other magic solutions that are mostly misapplied. Bit like DPC injection has been.
Guess there's more money in doing setup work + hiring out special kit than in just leaving a dehumidifier sitting & working.
OutInTheShed said:
If it's a concrete floor then drilling into it at random will potentially risk going through the damp proof membrane.
That would be my concern above all else. We like to think our houses were originally built with care and attention and that ‘professionals’ coming to work on our houses are going to actually know what they’re doing and treat it like their own - but they weren’t and they don’t. Drilling it seems like a recipe for trouble and digging the floor up seems mental. Although I suppose if it’s on insurance it might be an opportunity to upgrade the floor and whack some UFH in…..
Just give it an extra couple of months to dry out.
Sorry you’ve had to go through this, though. It’s one of my worst nightmares! So much so that I have a handful of leak detectors around the house connected to the house alarm.
Jeremy-75qq8 said:
Nice link. As above though, I wonder how they can measure the moisture content of the insulation mid-way between the holes. Do they have data about seepage rates? I suppose so. Sorry that this process might take a month.24lemons said:
Last weekend we unfortunately had a leak that resulted in the downstairs being flooded.
The kitchen and hallway are Lino which held the water but the lounge and study which were carpet were damaged resulting in the carpet coming out. We have had a dehumidifier running all week.
The insurance appointed drying team came out on Friday who immediately told me that injection drying would be the only solution. This involves drilling holes through the concrete floor into the insulation below to allow warm air to be blown into the wet insulation. This, he says could take 2-3 weeks or more.
This is obviously drastic. The moisture readings he took ranged from 3-4 on his meter. I don t know what they meant but he said he wanted a reading of 2.5 before he d sign it off as dry. The wall are all good as he put it.
He dismissed the dehumidifier and said I might as well turn it off as the insulation would never dry with the dehumidifier running.
My question is, is he correct? Nobody else has been to look at it and I don t want to do him a disservice but he s appointed by the insurance company directly, is he suggesting the best course of action for our property or his business? If I m being grossly unfair, I ll gladly hold my hands up and apologise but is it at all possible that there is another approach which could be investigated before embarking on such a major undertaking?
It certainly is logical these days to question everything. The kitchen and hallway are Lino which held the water but the lounge and study which were carpet were damaged resulting in the carpet coming out. We have had a dehumidifier running all week.
The insurance appointed drying team came out on Friday who immediately told me that injection drying would be the only solution. This involves drilling holes through the concrete floor into the insulation below to allow warm air to be blown into the wet insulation. This, he says could take 2-3 weeks or more.
This is obviously drastic. The moisture readings he took ranged from 3-4 on his meter. I don t know what they meant but he said he wanted a reading of 2.5 before he d sign it off as dry. The wall are all good as he put it.
He dismissed the dehumidifier and said I might as well turn it off as the insulation would never dry with the dehumidifier running.
My question is, is he correct? Nobody else has been to look at it and I don t want to do him a disservice but he s appointed by the insurance company directly, is he suggesting the best course of action for our property or his business? If I m being grossly unfair, I ll gladly hold my hands up and apologise but is it at all possible that there is another approach which could be investigated before embarking on such a major undertaking?
I'd be asking what the issue actually is with some water sitting between two layers of concrete in some foam.
If water has got into that space it won't have been as a result of soaking through the entire pad but finding a path where the top pad meets the walls. So any water is likely to have just found its way straight to the dpm. At which point it will slowly escape over time through the mortar joints to the outside world.
The second question would be regarding the pertinence of the moisture readings in what is a completely confined space. The tiniest quantity of water will deliver a high atmospheric read in a confined space. And let's not forget that a rapid new build will be seeing the insulation and top pour going down before all the moisture is out of the base and you'd be looking at years and years for the slabs to fully dry out.
Let's consider the reality that it often rains when the top pad is being poured, has rained prior so water is pooled above the dpm and the concrete co rains a huge amount of water. Then you have all the rain hitting the pad before the roof goes on. The house is then completed and sold as quickly as possible from that point. So every new build is going to have f
k loads of water in the concrete floor. Why, when a situation arises where some new water is added is this suddenly a major issue? It either got out before so will get out again or it never escapes and no one has any issues. The third question would be what the actual risk was of water in an environment with no organic matter? Moisture coming up isn't going to be great for wood floors but in theory they should be on a membrane and dealing with the flood water damage to the flooring is a separate issue.
Just politely question their logic and note what their answers are.
DonkeyApple said:
It certainly is logical these days to question everything.
I'd be asking what the issue actually is with some water sitting between two layers of concrete in some foam.
Maybe but I read it as the insulation being below the slab otherwise 1) he'd have been talking about drilling screed rather than a slab and 2) it would then have been easier to remove and replace the screed and insulation rather than drilling and drying for three weeks.I'd be asking what the issue actually is with some water sitting between two layers of concrete in some foam.
TA14 said:
DonkeyApple said:
It certainly is logical these days to question everything.
I'd be asking what the issue actually is with some water sitting between two layers of concrete in some foam.
Maybe but I read it as the insulation being below the slab otherwise 1) he'd have been talking about drilling screed rather than a slab and 2) it would then have been easier to remove and replace the screed and insulation rather than drilling and drying for three weeks.I'd be asking what the issue actually is with some water sitting between two layers of concrete in some foam.
Been there, have the wet T Shirt, burst pipe in the loft of a bungalow running for a number of weeks, ceilings down etc.
Ours was timber floor, not concrete but I'd say lift the carpets and dump them, if you've Karndean/Amtico etc lift it, it'll be holding water (we were waiting for the assessor for weeks and by the time they agreed what as to be done the water trapped under the Karndean destroyed the chipboard floor! Which also had to be lifted.
We had IIRC 3 or 4 commercial size dehumidifiers running plus heating to get the moisture out of the rest of the house. This was 2011 and the bill came to around £40K but the joiners fitting the replacement kitchen were travelling 4 hours a day rather than staying over. 4 hours work and 4 hours travelling!
Ours was timber floor, not concrete but I'd say lift the carpets and dump them, if you've Karndean/Amtico etc lift it, it'll be holding water (we were waiting for the assessor for weeks and by the time they agreed what as to be done the water trapped under the Karndean destroyed the chipboard floor! Which also had to be lifted.
We had IIRC 3 or 4 commercial size dehumidifiers running plus heating to get the moisture out of the rest of the house. This was 2011 and the bill came to around £40K but the joiners fitting the replacement kitchen were travelling 4 hours a day rather than staying over. 4 hours work and 4 hours travelling!
PIR/PUR insulations (Celotex, kingspan etc) can break down if exposed long term to moisture. For this reason the DPM is laid below (and not above) the insulation to protect it from exposure to moisture. Drilling from above should not compromise this so long as they don’t go too deep.
The behaviour of the older and less efficient Polystyrene insulation products is different to pir/pur and these can be laid in direct contact with the ground.
The behaviour of the older and less efficient Polystyrene insulation products is different to pir/pur and these can be laid in direct contact with the ground.
smokey mow said:
PIR/PUR insulations (Celotex, kingspan etc) can break down if exposed long term to moisture. For this reason the DPM is laid below (and not above) the insulation to protect it from exposure to moisture. Drilling from above should not compromise this so long as they don t go too deep.
The behaviour of the older and less efficient Polystyrene insulation products is different to pir/pur and these can be laid in direct contact with the ground.
It kind of begs the question if it’s vulnerable to moisture coming from above in a scenario like this, why is there not a protective membrane applied on top of the insulation? The behaviour of the older and less efficient Polystyrene insulation products is different to pir/pur and these can be laid in direct contact with the ground.
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