FLAT ROOF SEALANT ( and Applicators of same ) ??
 

Does anyone have experience of a substance which can apparently be used to SEAL flat roofs which are letting in water to the walls below ?
I have been told this might remedy my damp problem. But I do not know the name of the product, much less whether it actually works ?

And if so are there persons you can recommend to do the work ?

Re: FLAT ROOF SEALANT ( and Applicators of same ) ??
 

Have you considered joining this Facebook Group? "Building, Renovating and DIY in Portugal (No Adverts)"

Re: FLAT ROOF SEALANT ( and Applicators of same ) ??
 

I tried (and failed) once on a flat roof garage with one of those DIY "wonder products"

Total waste of time. This was back in the UK so got a proper roofer in.

Can't help with tradesmen in PT but from my miserable experience I wouldn't go the DIY route.

Re: FLAT ROOF SEALANT ( and Applicators of same ) ??
 

Products from Leroy Merlin https://www.leroymerlin.pt/Produtos/...ermeabilizacao

I used https://www.leroymerlin.pt/Produtos/...R_REF_85356294 sucessfully in Spain

Check the instructions thoroughly

Re: FLAT ROOF SEALANT ( and Applicators of same ) ??
 

I tried and liquid roof sealant totally didn't work; then I had a tar roll with aluminum outer skin set on top, and that does work.

Any of those liquid products might possibly work for a time, but the problem is the concrete below. If it's not very dense, hard, and stable then the product will fail after a time.
If it was dense, hard, and stable it wouldn't leak now.

Your damp might be due to water ingress from outside, or it could be condensation from inside; do you see any sign of water after rain that you don't see after a dry period?

Re: FLAT ROOF SEALANT ( and Applicators of same ) ??
 

Thanks for replies ( please keep them coming ). But first let me clarify............I have no desire or ability to do this job myself.......I am v much looking for recommendations for reliable person/s who have done the work successfully in the past and remedied the same problem.

Live........WHO set your tar roll etc. and are they in the Algarve ( I am at Eastern end ).

I am unable to say what happens after rain specifically as I have not been at the house for 14 months now. The problem has been reported by helpful neighbours who have a key. They apparently tried scraping the mould etc off the back wall and re painting..........leaving windowns open and such.......but it came back. So it's not a condensation problem.

The house is only 23 yrs old..........I don't understand how a roof that young can fail on its basic task of keeping rain out...........

I am really anxious to get something done now so that the windows can be left open all summer and the place can dry out during the heat of July and Aug..

I have had terrible terrible problems with building work on a previous house, costing huge sums of money. I am really anxious not to have a repetition of that nightmare . Hence I really would appreciate a recommendation for someone who is known to do really solid work at a reasonable ( not the cheapest ) price.

Re: FLAT ROOF SEALANT ( and Applicators of same ) ??
 

PS : if the SEALANT product even provided protection for a year or two presumably that would allow the interior damp to recover , paving the way for a longer term solution to be sought but at leisure, rather than in a rush ?

My guess would be that the sealant thing just takes a day or two to apply ? Is that correct ? 90 sq m roof approx. I think it's covered in Sta Catarina tiles at the moment.

Re: FLAT ROOF SEALANT ( and Applicators of same ) ??
 

COULD you be a bit more specific as to what problem you used this product on ? What was the roof made of ? Was it a flat ? Did it solve the problem completely ?

Re: FLAT ROOF SEALANT ( and Applicators of same ) ??
 

It was an old cast concrete garage roof.

However what you are doing is wrapping an aluminium covered bituminous sheath over the whole roof.

It is important to ensure the whole sheath is sealed especially at the joints.

There is also a bituminous paint that should be applied first as it provides a key to the concrete.

Then the sheeting is applied with a blowlamp melting the paint and sheeting together.

I also successfully used the same method over a conservatory I built with a sloping plywood roof which was then covered in a bituminous tiles. However for this I should of used the bitumous sheeting without the aluminium layer.But the tiles were an after thought.

Re: FLAT ROOF SEALANT ( and Applicators of same ) ??
 

I'm on the west coast, and it was 10 years ago, so I can't help with a person to do the job.
Actually, I guess 10 years is proof of concept.

I had it done by a local guy who specializes in it; he charged too much, but I stole his power.
I watched him work, and the next time (roofing over the top of a sea container) I did it myself.