Soaking wet cavity walls and a defective blocked cavity tray

This video shows the cavity tray was never inspected, and cleared of debris before the cavity wall insulation was installed. The bitumen cavity tray has also broken down, and needs to be replaced. Unfortunately this is a common issue that I come across now. When purchasing a property please consider a proper survey to evaluate defective cavity wall insulation installs, and see if the property is guaranteed, and if the guarantee is actually valid. I often find if there is the smallest of pointing issues on the opposite side of the building internally the guarantee isn't valid.... you may need to budget for extraction, and possible replacement wall ties.
Costs can spiral where scaffolding is needed, cavity wall insulation removal, wall tie replacement, repointing, and ventilation.
Click on my other videos that show other issues of cavity wall insulation where the sub floor ventilation is blocked and rot occurs in the suspended timber floors. All of this work is very expensive to repair, so make sure you instruct a surveyor.
Any questions put them in the comments below, and I'll answer them for you.

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[completepreservation]

Have you had issues with cavity wall insulation?

[Oliver-tmjm]

Excellent video - Explanation at the end was the icing on the cake. Look forward to more

[davephilips]

Good investigation to find the cause Ross.

[showme]

I've just done this job on my 1962 house, a south facing wall, get all the extreme weather, hot cold, wet windy, and the damp tray was cracked just like that one. But the main reason for rain water getting in was the window fitters had cut the water tray back to the inside line!!!!.

[chrisholt]

Brilliant film and explanation, thank you.

[davidcoleman]

Brilliant video Ross!Yet another different aspect of what can happen.I would have thought that stainless steel cavity trays should be the norm, so it could be fit and forget.I see quite a few old trays made out of various materials being replaced on youtube. 🤨❤👍

[donaldlee]

Great video demonstrating the problem. Is the solution to pull out only the first course of bricks above the window, and install a new tray and waterproofing, or if more than just the first course, how many courses up? Hopefully you don't need to go all the way up to the roof in most cases.

[wladjezu]

Rescue and repair existing of cavity wall insulation

[johnnoble]

Great video. My mams ex council house has had a problem with damp in cavity the wall insulation was wet through. I've cleaned it all out as well as rubble. Is that all I can do. Cheers John.

[johnmcgill]

Hi Ross, I have come across a similar problem in my gable end cavity wall and, thanks to your explanations, have figured out where the problem lies (I think!). After removing some bricks it is clear that debris is bridging the physical dpc. However, the wall also has cavity wall insulation retrofitted at some point which is mineral wool. This is wet in places up to a height of about 400mm. The house is on top of a hill and the wall is exposed to lots of rain. I think cavity insulation should never of been added in this instance.

My question is if I remove all the cavity debris to 225mm below the physical dpc, could the cavity insulation fall down into that gap and also bridge the dpc at a later date? I know mineral wool is supposed to repel water but be good to get your opinion?

[dadisgreat]

Nice diagnosis of the problem ... but what's the solution?

[waynebritton]

How much will that cost to repair. As I'm having same problems with my living room window over the weekend we had the storm with heavy rain and it came through my living room window and made a complete mess but the daft thing is we have had the same problem for the past 3years it gets fixed by a company called MEARS that work for the LCC they told up that it was fixed every year but never is this time I can't get them to fix the problem as I bought it last year just after they sed it's fixed lol so I'm hoping the my house insurance companie will sort it out wish I could send you pictures of the damage its done on the inside then again dont think it would surprise you

[paulwibb.]

Is this the type of insulation that's pumped into the cavity, , years after the house was built, ?

[ssbb]

Hi Ross. My extension is built from concrete blocks inside and out. Im suspecting that the cavity insulation that was done around 5 years ago before we purchased it wet. Is it ok to remove a block internally to check? The plasters fell off the wall so wouldn't be an issue cosmetically.

I'm not massively clued up on houses but my other concern is there doesn't appear to be any weep vents, it was built somewhere between 75-85 so unsure if they were built differently?

[HairlossExperiences]

How long should a cavity tray be? Should it be one continuous tray all the way around the house?

[PKSiAMiAM]

Hey Ross, thanks for these. Where can I get these surveys thuroughly carried out? I want to get a closed cell cavity installation carried out followed by external insulation in the future (this is a few years down the line.) Wanting to retrofit my home to passive House standards with HVAC etc. Is there anyone who carries out the inspections? All I can find is people who want to install the insulation or are saying don't get cavities filled.

[graykev]

Hi - I don't have any problems but have recently found out what weep holes are as i noticed wasps going in/out of mine. Not an issue as i think they are too small at the other side for them to enter. Anyway that led me to your video and i am wondering how the water actually gets into the cavity in the first place? I don't mean if there is a problem i just mean in general. Presumably it is rain? but how does it get behind the bricks outside?

[darrens]

Also there's no weep holes in the perpend joints between those blocks either, so there would be nowhere for the water to go anyhow. It'd just build up on the failed cavity tray.

[MARTINA-gctq]

where was the moisture coming from? if it was in the cavity was there a faulty gutter?

[danielkorczakowski]

Hi I live in a 1950s house just cleaning out cavity and on the of the house concrete past the floor height
Kids regards