# ??? Sealing a Concrete house roof ???



## Salto_jorge

Does any know or have experience sealing a concrete house roof. I have a basically flat roof and its has some cracks in it. A plumber when looking at my water tank told me that the roof needs to be sealed.

What do I need to purchase and how much should something list this cost.

Thank You

Salto


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## moisheh

You need "impermiabilizante". This is a white elastomeric sealant that comes in 5 gallon pails. But first you have to seal all the cracks with a special compound. Then you apply a mesh fabric over a thin layer of the sealer. Lastly another coat of sealant. Dont skimp and please do not buy the cheap stuff. Get one with a minimum 5 year warranty . Better yet the 10 year. If you are having a workman apply the product do not let him add water!! Not a difficult job and will last for years. Does your roof slope enough for drainage??


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## Salto_jorge

The roof has a very slight slope. We have cracks where the outer calls ans the upper concrete slab meet plus some cracks in the large slab itself. 

Is this the name : imperbiabilazante

Do you recall how much this costs per bucket ?

Salto


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## sparks

impermeabilizante 

You can look around on Mercado Libre. 3 year seems to be 5-700 per cubeta (5 gal+/-)
Impermeabilizante en MercadoLibre México - Donde comprar y vender de todo.


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## moisheh

Home Depot carries a few good brands and they start at about $ 800 pesos for 20 litres. Then you need the crack filler, fabric and the application tools ( heavy brushes or rollers).


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## mexliving

the 7 year will run about 940 pesos..... you can ask for a local worker to find someone who knows how to do "lecheria" its a cement water mix with sealant and something else... they pour this liquid water cement mix.... prior to doing the impermenable...


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## Salto_jorge

I called around and found a product at Home Depot that does not require using the mat roll. I think that a mat roll can be a real mess.


Its called, thermotek-blue (Mexico) . Found out that you pain everything with a special primer, then use plastic cement (fester) followed by two coats of the Impermeabilizante.


Has anyone used these products ? What did you think about them.

thermotek-blue (Mexico) 19 liters for 699
Primer 19 liters for 435
plastic cement 4 liters for 196


If this stuff is good, I just need to find someome to do the work? Amy idea what labor costs an hour for this kind of job ? Maybe 50, 75 or 100 ?


Salto


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## moisheh

I would nbot apply any product without the mesh. It is not hard to apply. I did our own roof and it was no big deal. But is very messy. Most workers will do the job by the sq. meter. 699 pesos is not very expensive. I would look for a better product. As I stated look for the 10 year product.


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## Salto_jorge

The only good thing about the thermo-tek blue is that it contains filers in it. Due to this fact the material is not supposed to be thinned as people often do with other products. This new product is also from a mexican company


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## jlms

Get somebody that knows how to do this properly.

At the very least open the yellow pages and look for Impermeabilizante, just looking there I found IMPERQUIMIA who claim to apply anywhere in the country and give you a guarantee.

DIY or just the friendly handy man is not recommended!


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## conklinwh

I think that the last couple of notes have the right approach. I went to a large local hardware store where I have gotten good info on problems in the past and where I could enhance my somewhat limited Spanish with the right construction words.
The owner was able to tell me both whom the best people were for the job and the correct materials, including the mesh. One of the great things here is the labor/material cost difference. Since materials are such a large part of any project cost, it is easy to stifle myself in terms on doing unfamiliar projects. I hate to say it but I paid the construction person and helper 300p to do a 15' x 21' boveda roof including filler where necessary.


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## Salto_jorge

I purchased thermo-tek blue at HomeDepot for 699.00 a 19 liter pail, plus brushes.


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## tepetapan

I have used the Comex brand " TOP COAT" and have had very good luck with the product. It comes in a 3, 5 or 7 year formula that has a blue tint when applied and turns white when cured. There are other colors but white is what I´m looking for. 
I have never used the mesh since my roofs are sound and dry for the most part, even with the 150 inches of rain (or more) a year. I use it mainly as a preventative measure and a reflective coating ( as is the white) to help lower interior temps. I pressure wash the concrete, follow the directions on the lable and it sticks tight to the concrete for years.


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## telcoman

There are a few products that are concrete based and actually penetrate the existing concrete & grow crystals in the pores. These have a high hydrostatic resistance. It will prevent water from seeping up through a basement floor for eg.The problem is you cannot apply this if the concrete has been coated with paint or other plastic sealants, since it needs to penetrate the concrete. If the concrete has not been painted, then it is your best bet for permanent waterproofing. It is what most large Aquariums use on their enclosures. Here is one company:

Waterproofing Made Crystal Clear


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