Wall cladding falling off, why? would more drainage be the solution?

[Richard Hamlett]

Zclad 2

• Richard Hamlett
• 6 Sep 2018

Z Clad 1

• Richard Hamlett
• 6 Sep 2018

Hi Guys,

So recently bought some exterior wall cladding (Zclad) spent about £350.00 on adhesive, treatment and the cladding.

It's all fallen off, I contacted the company who say it's probably because its a retaining wall and it's getting too wet (even though their website doesn't say anything about retaining walls).

1). So does anyone know the reason why its falling off? Is it because it's getting too wet so the adhesive isn't bonding properly?

I have draining built in across the bottom of the wall and the corrugated pipe comes out of either side, they informed me that putting concrete holes in the bottom of the wall would solve the problem by adding more drainage.

2). So my second question is, will these holes I drill in actually help keep the cladding stay on? As it's a retaining wall surely it's going to get wet regardless of how much drainage is put in. I just don't want to waste my time putting holes in the bottom of the wall and then the cladding falling off again anyway.

thanks in advance !

 

[Charlie George]

Can they be cleaned off ? i would use an SBR slurry on wall and back of tile, and use a suitable waterproof adhesive,and make sure there also supported off the existing foundation, you could also add some small angle brackets to wall and tile too.
And as you say unless wall has been tanked its going to get damp regardless of how many weep vents you have.
jim
edit noticed they come with fixing brackets, did you use these?

 

[Richard Hamlett]

Brilliant thanks Charlie, They told me to just use the cement based adhesive they supply and it'll be all good. Never mentioned anything about the SBR slurry.

In regards to the brackets - no they said these do not need to be used on walls below 2M high. the wall is about 1M high.

thanks a lot!

 

[^woody^]

Even normal cement should stick to a damp wall for a long time. It's when walls are constantly soaking wet that coatings fail, and even then it more probable in winter as things freeze, not summer.

It's unusual for none of that adhesive to have even stuck, so the first thing to consider would be the surface preparation and application. Did the adhesive dry too quick? Was the wall surface loose or dusty? Was it applied too thickly (it looks quite thick)? Were the tiles pressed home fully?

A cement slurry coat is not the answer.

You can get adhesive for damp conditions.

Drain holes wont be any use unless you have proper drainage at the back of the wall to divert water to the holes in the first place. Even then this does not stop the wall becoming damp, it just prevents water pressure build up.

 

[^woody^]

BTW, the coping stones have too little over-hang, and all the rain is being directed down the face of the wall

 

[Charlie George]

Woody why is SBR not suitable in this case? plenty of evidence to suggest otherwise.

 

[Richard Hamlett]

okay thanks for the input Woody,

- applied in an overcast day or evenings after sun had gone down
- wall was prepped properly dusted down and cleaned (no harmful chemicals)
- I used the recommended 10mm notch trowel
- with the coping stones they had 5cm overhang which compensated the width of the cladding. I see it may have needed more, but still doesn't really make sense as the walls their examples used didn't have any over top protection so I believed I was actually unnecessarily protecting it with the coping stones.

I'm almost certain its the rain that has caused this, due to the fact everytime it rained heavy a few more pieces fell off!

thanks,

Richard

 

[^woody^]

Woody why is SBR not suitable in this case? plenty of evidence to suggest otherwise.

Not that it's not suitable, but not the answer on its own. I know it's a common primer, but if the adhesive is not sticking to the concrete blocks now then it does not automatically mean that they will stick after a slurry.

I was really getting at looking at the other possibilities for the failure first.

 

[tomfe]

Looks like they have dropped slightly so not stuck. These will be heavy tiles, knock a couple of nails in to support them while they go off.

 

[Driveiton]

Did you find a solution to the problem and what was it? I forsee a similiar problem in a retaining wall I need to clad.

 

[dontbelieveawordofit]

Can they be cleaned off ? i would use an SBR slurry on wall and back of tile, and use a suitable waterproof adhesive,and make sure there also supported off the existing foundation, you could also add some small angle brackets to wall and tile too.
And as you say unless wall has been tanked its going to get damp regardless of how many weep vents you have.
jim
edit noticed they come with fixing brackets, did you use these?

holy smokes. sbr?