Hi, my friend have a three-storey house made of cement with roofdeck. He often talks about how he experiences water leaks appearing as water marks on his painted ceiling on the top floor, whenever there's rain. He said he had been applying the paintlike waterproofing on said deck but has become too engrossed on it once every year. After finding and browing through this site, I found the forum an opportunity to learn about the types/kinds of waterproofing materials available in the market. I'd be grateful if there is anybody who can give me advise on what brand/make/process of hi-quality waterproofing and long lasting for a cement roofdeck of about 150 sqm. Anyone? tnx
Re: Waterproofing a cement roofdeck
Consider epoxy. It is expensive but it is durable and definitely watertight.
I'm a big fan of Cord. I've used their products for saltwater tanks and on my boats. I am sure their application engineers would be happy to discuss your options with you. I think they can even contract the work and give you a guarantee.
Re: Waterproofing a cement roofdeck
The big problem about waterproofing is movement of the surface on which it is applied. Some of the hard waterproofing products like cement based products will crack if the concrete on which it is applied cracks. Then leaks start again.
Cracks occur more regularly where a roof deck meets a wall. In instances where movement is expected, the best waterproofing will be those that are flexible. Some elastomeric paints are guaranteed to be flexible.
For really tough jobs, I suggest for your friend to bite the bullet and invest in hot applied rubber or asphalt type waterproofing. The sheets are fused together and to the roof surface with heat. And the asphalt will be flexible enough over the cracks.
There are many suppliers of this type of waterproofing as it is not really a DIY operation. But ask your friend to get referrals and guarantees.
Re: Waterproofing a cement roofdeck
2diy4 is right about your needing flexibility which epoxy may not live up to. Also, the UV will destroy the epoxy so it would need a topcoat.
Re: Waterproofing a cement roofdeck
Thank you guys for the inputs. I just visited an ACE hardware near our place and found out from a sales clerk that there really are different kidns of sealant for every surface i.e., metal, wood, plastic, cement, etc., not to mention the type of materials used as base material for sealer. There are also surface sealants as well as mere joint sealants, the signs on the can also states that it is A waterproofing sealant. Honestly? I am awed by a variety of sealants you can buy, and if you are not a discerning buyer, those sales clerks can take you for a roller coaster ride. Nonetheless, I found what I am looking for that costs about P2,400 per pail. Is that masonry sealant good enough to last a few years?
Re: Waterproofing a cement roofdeck
sir try this one.....
Re: Waterproofing a cement roofdeck
Nice link, good site, thanks fortuner13
Re: Waterproofing a cement roofdeck
For long term use, hot applied membrane waterproofing is the way to go. Some even have gravita (little gravel) on one side to act as non slip if the membrane will not have a topping or pavers on top.
Re: Waterproofing a cement roofdeck
For DIY applications on your roofdeck waterproofing, i recommend using Flexseal elastomeric paint. 7 coats is sufficient to waterproof your deck. There are new types of elastomeric paints out there in the market today but none of them are recommended and advised to be used for waterproofing your deck roof. Try buying two different colors of flexseal then alternately applying them on the whole deck roof.
Re: Waterproofing a cement roofdeck
Hi Bobby, Is this the same with that I found/saw at Handyman, branded as "Thoroughseal" that is supposed to be in powder form, stuffed in one gallon can container? The Sales Clerk says it needs to be dissolved with right amount of water and applied on roofdecks? I am aware that there are many brands, and makes of waterproofing material, and now, even DIY-friendly. Is it?
Re: Waterproofing a cement roofdeck
i recently had my roof deck fixed since the original contractor obviously did a very lousy job. another contractor also gave me a quote to do the job for 25k.
first step was for me to patiently remove the existing waterproofing paint applied by my old contractor.
second was to trace the cracks on the cement roof that caused the sipping of water to the 2nd floor.
third, after marking with a chalk the cracks, i used a grinder to make the cracks a little bigger in a "V" shape about 1cm deep.
fourth step was i vacummed the cracks and cleaned it thouroughly to make sure their were not dirt left.
fifth, i used a commercially available hydraulic cement to seal the "V" cuts. Hydraulic cements dry very fast and application has to be fast. correct powder & water combination must also be obeserved.
sixth, after making sure that all cracks are sealed with hydraulic cement, i placed a layer of vulca seal as reinforcement. i was suppose to use asphalt but i did not know where to buy.
seventh, after the curing of the sealant , i re-cemented the whole roof deck with an inch of cement ( make sure you do this when its not so hot & humid since the first time i did this, it was during the hottest day in Manila and the cement dried so fast and in just a few days, cracks emerged so i had to do it all over again). Make sure also that the clevy of the re-cementing is perfectly angled to the drain/s. make sure also that you make the old cement a little rough ( i used a grinder) to amke sure that the new layer of cement will have a good grip.
eight,i re-painted the newly cemented roof deck with a commercially available elastomeric paint. i applied 6 layers and made sure that the corners & sides had thicker coatings.
it has been 6 moths and i never had any single "tulo".
i plan to do a recoating of the roof afer the rainy season.
i only spent around 7k for everything including labor.
i hope this helps. ;D
Re: Waterproofing a cement roofdeck
Congratulations on a good job. What brand elastomeric paint did you use? I'm thinking of doing a test on elastomeric paints and knowing brands popular with members will help me. Can someone help out with possible tests? I think it was bobby who mentioned painting the elastomeric paints on a sheet of hardiflex pour water and see results. There was also a suggestion on making a cardboard box, painting the inside with several layers, then pouring water.
Re: Waterproofing a cement roofdeck
the brand i used was a-plus sir...............pretty good.........well at least as of this moment ..............but i plan to paint another coating and maybe i will try flex seal as recommended by one of our friends here in pinoy handyman...........
Re: Waterproofing a cement roofdeck
The problem with asphalt is it cracks. even the blowtorch membrane cracks in time and though its the most accepted, it does work for awhile.
Asphalt based products when subjected to heat tend to crack after awhile.
Also it has a tendency to delaminate (kapak) then when it becomes brittle, it cracks and water will seep in.
you can use our waterproofing product called primedri fwm which is flexible, adheres to most if not all surfaces, durable and uv resistant if not uv proof.
Re: Waterproofing a cement roofdeck
hello!
how about covering it tiles? would they prevent water?
