Roof " water sealing "

malko

Campesino !! :)
Jan 12, 2013
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I had tarmac kind of thingy on the roof against water infiltrations.
It has actually served us ok ( but only just over the years ).
I have ripped it all off now...... :( :(....... too old, lots of leaks so the water gets caught between the ciment of the roof and the "  tarmac ".

Anyway, we have deceided on the " silicon"  thingy this time. 
Btw, the roof is flat ( well mostly, but the not flat bits have roof tiles, somwe ok there ).
I am guessing there is 300 + square meters ( i am doing my own mesures today ).

My question is how much do i need to expect to pay for the " silicon" ?
And for the work in itself ?

All answers welcome :) 
Thanks all.
 

windeguy

Platinum
Jul 10, 2004
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Silicone based sealer perhaps. (Silicon is a metal. Silicon Valley is near San Francisco, and Silicone Valley is near Los Angeles).

As for the price, there are various product levels available and everyone will quote a different price for the product and the labor.

For a flat roof, I am not sure how will it will work. Water has a way of defeating such products.
 
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kcdmps

Member
Dec 6, 2014
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I had a car port roof leak a few months ago. The roof didn't have much of a slope/pitch and it was leaking in the middle part that had sagged slightly. It took me couple of months of trial and error to find the source of the leak. It turned out the water was seeping in from the edge toward the low area at the middle of the roof. I used silicone roofing cement along the edges to stop the leak. Asphalt roofing cement probably works just as well at a fraction of the price.
 

pularvik

Active member
Jan 2, 2011
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after years if paying different guys who supposedly knew how to fix it, we hired someone to  scrape it down to the original cement,  apply a bonding agent, then lay down new cement in  such a way to create slopes for the water to drain.  Unless the water is drained no matter what you do to  the roof it will fail.  You must eliminate water pools.  Then whatever you put on  will work and if you go into a big paint store you will see the whole spectrum.  Just be sure its applied thick enuf.
When you finally get it done do not be complacent-------check annually,---for cracks and to make sure there is no water pooling. Most of the roofing materials will need recoating in a year or 2.  
 

dv8

Gold
Sep 27, 2006
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we use this product:
http://www.lancoproducts.com/featured-products/37/urethanizer

re-coating is done every two years or so. the first application will use more product than further ones. i think a bucket costs 7k pesos? it works well for us.
the roof needs to be dry and no rain for a day or two afterwords for it to properly seal the surface and dry. you'd need to check the roof thoroughly before application and fix any damage/cracks.
 

Kipling333

Bronze
Jan 12, 2010
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pulvarik ..I agree 100% . Rooves in the DR seem to be designed to give problems and mainly because they are too flat so the drainage is poor . There has to be some reason why there is no pitch on the rooves here but no one tell me it .The only solution to big problems is to get back to the cement and start all over again ..short cuts have short lives .
 

ctrob

Silver
Nov 9, 2006
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The correct method is to hire a rubber roôf guy. They'll give it a sloped pitch using insulation, than lay rubber sheeting. No môre leaks fôr 50+ years. Everything else is a tempôrary fix.

You'll also gain a cooler interior by having an insulated ceiling.
 

william webster

Platinum
Jan 16, 2009
30,247
4,328
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Our roof is 9 yrs old .
The flat section that holds the solar panels is concrete with a membrane over it...rubber or tar paper.

It just started to leak a few months ago... only in heavy rain when the drains can't cope with the water volume.

It was repainted with something.... dry weather, 2 coats .

Seems to work.

As said above , they sell a sealant paint to do the job..... until you need to go back basics and start again.
 

beeza

Silver
Nov 2, 2006
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we use this product:
http://www.lancoproducts.com/featured-products/37/urethanizer

re-coating is done every two years or so. the first application will use more product than further ones. i think a bucket costs 7k pesos? it works well for us.
the roof needs to be dry and no rain for a day or two afterwords for it to properly seal the surface and dry. you'd need to check the roof thoroughly before application and fix any damage/cracks.



I can concur.  My house has a concrete Bermuda style roof and leaked like a sieve.  We spent days stripping off the numerous layers of previous paint to get down to the bare concrete.  We also used a high powered pressure washer to remove all of the old paint.  My roof is 600m sq and it took ten of those buckets at 7,000pesos  each to give three coats of paint.  It goes on blue and turns white as it dries.  It was done around six months ago and so far so good.

Another benefit of this paint is that it says it reflects up to 90% of the sun's radiation.  I can confirm that the house is significantly cooler inside since we repainted our roof.
 

AlterEgo

Administrator
Staff member
Jan 9, 2009
23,069
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South Coast
The roof on our house is from the early 80s, and after decades of sealers we still had some seepage.  Mr AE hired a crew to come in and crush the top cement layer, then had new cement poured, and then the sealant.  It worked
 

kcdmps

Member
Dec 6, 2014
142
22
18
There has to be some reason why there is no pitch on the rooves here but no one tell me it .

Homes with high pitched roofs are more prone to hurricane damage.

One time I had a roof leak that was caused by a small hole. I don't know how the hole got there but the fix was simply a matter of putting a small dab of asphalt roofing cement over that hole. I could have replaced the whole roof but it was unnecessary. That little dab of roofing cement has held up for over 30 yrs now.

Before you dump a lot of money into the problem, take a good look at the area of the leak, look at various options to fix it, and do a cost-benefit evaluation. You could end up saving a bundle.
 

malko

Campesino !! :)
Jan 12, 2013
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I can concur.  My house has a concrete Bermuda style roof and leaked like a sieve.  We spent days stripping off the numerous layers of previous paint to get down to the bare concrete.  We also used a high powered pressure washer to remove all of the old paint.  My roof is 600m sq and it took ten of those buckets at 7,000pesos  each to give three coats of paint.  It goes on blue and turns white as it dries.  It was done around six months ago and so far so good.

Another benefit of this paint is that it says it reflects up to 90% of the sun's radiation.  I can confirm that the house is significantly cooler inside since we repainted our roof.

Good point. 
I didnt say that since i tore off the tarmac, the house is much cooler.
So i was down to the "original"  ciment,  i just painted over it with a popular brand mix ciment / paint (  cant remeber the exact term ).

But now I am looking for a more "durable "  solution.  Even though i do understand i might have to give it another coat evey year or so.
 

malko

Campesino !! :)
Jan 12, 2013
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the other alternative is to put another tin roof over top

I was thinking of that......not too sure my better half will agree though ;) ;)

Also, it could be a hassle as I dont have gutters.  The drains are moulded into the roof top and the tubes ( also moulded in) carry the wated to the conuco.

Futhermore , I have 5 "domes"  where the ceilings are not flat, but more like a coupole (?), those parts have proper roof tiles. So I would have to find ways aroumd that too.
 

william webster

Platinum
Jan 16, 2009
30,247
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Run the tin to drip into the gutters...easy

If the 'cupolas' aren't leaking - they're out of the decision

You can do it Malko....
 

malko

Campesino !! :)
Jan 12, 2013
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Run the tin to drip into the gutters...easy

If the 'cupolas' aren't leaking - they're out of the decision

You can do it Malko....

But the gutters, that are not really gutters, are in the ciment, if you see what I mean. No " apparent " gutters, everything is within the cement of the roof and walls.

So it would mean installing gutters all around the roof. So extra cost ( comparing with waterproofing the existant roof ),  and more importantly it would be much less esthetic........

Also, some time in the futur, I have the project of a roof top terrace........
 

malko

Campesino !! :)
Jan 12, 2013
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The drains are not on the edge ofthe roof, they are say 1m or 2 from the edges......
And the edges have a lip ( for esthetics ) of say 50 cm high, and the same width....... so its impossible to have a tin roof drip into them.
There is also 2 centered ( well OK, not centered, but not on edges either ) " cuppolas " , so I would need 5 or 6 diffrent structures for 5 or 6 diffrent tim roofs :(   it would end up looking like a third-world disney castle :(