Penetrating damp question

29 May 2020
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United Kingdom

I'm looking for a little guidance and hopefully first hand experience.

I had a terrible leak from a cavity wall onto a ceiling below. At a guess I would say 3-4 pints.

I'm sure this wall has no cavity trays at the
base of the wall ( it does just below the roof) and im trying to figure out if this amount of water is more likely to be caused by leaking flashing or water penetrating the brick.

I've posted this issue on this site before so I know the general area of the problem but every builder I've had visit doesn't seem to think the leak is due to lack of cavity trays and even though they agree they should be there they don't seem overly concerned that they are not? Most think the flashing needs resealing and the mortar joints possibly repointing and maybe brick sealer applied.

Is retro fitting cavity trays not done that often as I'm having a heck of a time finding someone who will do it! I am at a loss.

Any advice?

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Simba_ali, good evening.

Sorry no answers but?? some questions.

What age is the property?
Is it a flat?
Am I correct, you have a water stained ceiling? what is directly above the stained area? is it a roof area?

Any chance of an Image or two of the internal damage and if possible the roof directly over the stain??


Property is 6 years old,( covered by 10 year warranty but need quotes first so I can claim once this is done b)

It's a 3 storey house with a balcony and the wall is supported by 2 rsj beams and a room directly underneath.

I've attached a pic of the wall and room below. It's worth mentioning I know the flashing leaks as I've tested it and water comes directly out of the hole in the ceiling (in the picture) so that definitely needs fixing but it was whether it looks like a combination of just the flashing/rain penetrating the wall or is it clearly evident it's the flashing.

It has happened twice in 4 years, both during storms. Normal rain seems fine.


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Simba_ali, good evening. again.

Looks as if there is a definite correlation between the defective area of the Balcony and the water damage internally.

I would "proceed with caution" in that do the Warranty Company require you to use specified repair contractors? I ask because down the line, the warranty company could turn round and say you have voided the conditions of the warranty agreement by not using a specified Company??

If it were me?? I would send images of the internal water damage, even if you can offer them access [difficult with C19] to view directly the damage. and get the warranty company to agree that damage exists, then move on to getting the warranty company to accept your choice of repair contractor, all ahead of commencement of work, why. as above??

OK I will come clean, I do not fully trust Warranty Companies, they are akin to Insurance Companies, the small print is worth looking at???

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Has the roof covering been checked? What about the joint beneath the cill?

I did contact the warranty provider who told me to get quotes to fix the issue which is easier said than done.

I have had builders / roofers / carpenters inspect who can't point to any flaw without tearing the area apart which I am hesitant to do because as you pointed out i don't want to void the warranty.

I haven't been able to process the warranty further as covid has slowed the process down and no one can offer a definite solution at this point.

What i can tell you from my own investigations during lockdown is that no amount of rain falling directly on the balcony decking has caused it to leak. Or show up on the ceiling It has only leaked twice which were in the 2 storms this year in February and March which were wind driven rain.

I have managed to make it leak by pouring 3 watering cans directly onto the flashing upstand and it shows on the ceiling in 10 minutes dropping through that hole in the picture. It also looks like the mortar has started to erode from where the rubber flashing is in the brick and there is a little movement when pressing the flashing. I have temporarily covered the joint with sealant.

I know water is penetrating the flashing so I will get that fixed, but I don't know if it's just the flashing or likely to be water penetrating the brick (lack of cavity trays) because I dont know how much water can normally pass through the outer skin. Also no builder has seen this as a problem or they won't willingly acknowledge it. They all say weep holes are only for condensation in this area of the country which I know it absolute rubbish.
If there was no cavity tray then the place would have been leaking since it was built.

If there are replacement doors and balcony/roof covering or flashing then those would be more likely to be an issue.
The Cavity tray situation is strange....the wall has weep holes 4 bricks from the top all the way along and there are weep holes over the balcony door.

There are however no weep holes at the base of the wall near the flashing so they have either forgot to put cavity trays here or they have put them in but with no weep holes.

So in theory the upper half of the wall is protected from penetrating damp just not the bottom half.

I also purchased an inspection cam which allows me to look into the roof space where the hole in the ceiling is when it's heavy rain and I never see any water. I can't quite look up th cavity though to check for a cavity tray...
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It's not so much adamant but more paranoid! :LOL:

The problem is I know they should be there but I'm not sure if that is the underlying cause of the leak. Also most builders shy away from retrofitting cavity trays and treat it as not a big deal which is making it impossible to move forward.
Simba_ali, good evening. again.

Must admit I am slightly uneasy about this sort of situation?

It appears that the Warranty Company is taking the easy way out, in that they tell you to organise all the different trades, then possibly at the end of it all tell you you are not covered for "That"

Can you not go back to the Warranty Company and get them to undertake all the requisite repair work??

This system or a large chunk of it has been used by Insurance Companies for years, the name of the game is "Cash Settle the Claim" that is get the mug, sorry the policy Holder to accept a cash settlement that has been costed at just a small amount over the cost to undertake the repairs.

Why? Several reasons.

1/. The claim as far as the insurer has been settled, it has gone away, no further action.
2/. The Insurer does not have to engage the services of one of their preferred building repair contractors at a cost, to the insurer.
3/. Insurer might get away without paying VAT, Vat is not included in the Cash Settlement made, to re-claim VAT the Insured has to prove VAT has been paid.
4/. If the repair in some way fails once a cash settlement has been made, or the extent of the repair cost increases, the insurer simply states that they have made a "Full and Final" settlement. If the insurer undertakes repairs then the Insurer is liable for additional cost incurred.
5/. The insured does all the running around organising all the various trades. can be somewhat time consuming???
6/. if you use the insurers contractor there is at least a 6 Month guarantee on the work, if there is a cash settlement, the Insured is [shall we call it?] on their own??

It appears that the Warranty Company are getting doing things on the cheap?? and on their terms, what ever they are??


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