BajaNomad

Impermeabilizantes

weebray - 5-10-2016 at 12:02 PM

Whew, seven syllables. My friend just sent me this comment about the stuff. Anyone have anything to contribute?

"My thinking here is: this stuff is just thick paint and the film left over after the solvent (usually water) evaporates. The only variable here is the % of solids in the mix. I have used a variety of brands from the 1700p/cubeta to 350p/cubeta. The cheap stuff was noticeably thinner than the 5 or 7 year stuff but the result was just a thinner film coating. I have never found ANYTHING that lasts more than 3 years. I have used stuff costing almost 2000p/cubeta. The name brand was Pasa but it was really no better than the 5yr. generic stuff costing +- 500p. Are we just paying for advertising? Any comments, thoughts?"

I will add here that our results concur but would add that we use membrane with the first coat and cover that with otro mano. We have used it on concrete and lamina roofs. Some of the vendors here in La Paz now have a product with fibers in it which they tout. ???

chippy - 5-10-2016 at 12:15 PM

I used the stuff for years. Its much better with the membrane but it still won`t last more than a few years. The more pitch (pendiente) the longer it`ll last.

I finally bit the bullet (5 years ago) and went with torch down (20 yr.). It should outlast me.



[Edited on 5-10-2016 by chippy]

woody with a view - 5-10-2016 at 02:52 PM

I used TPO on a trailer roof. Had a bunch of leftover from a new commercial roof install. I think it comes in 10' wide rolls that heat weld together, not torch down. You could nail the top edge and overlap the next course and heat weld it with a heat gun, just glues down and termination bars at the walls. It will last forever and can be adapted to a pitched roof easily.

bledito - 5-10-2016 at 05:21 PM

torch down last the longest cover with the white coating after torching down

woody with a view - 5-10-2016 at 05:49 PM

TPO 35 year: http://www.gaf.com/roofing/commercial/products/single_ply_ro...

Torch 15-20 year: http://www.gaf.com/roofing/commercial/products/modified_bitu...

weebray - 5-10-2016 at 05:56 PM

I appreciate the responses but for a number of reasons torch down is not appropriate. We are not "paint" guys and were simply wondering what impermeabilizante is made of and if the various products were mas o menos egual. Is it necessary to spend 2X the $ for a name brand? It's like: Is Grey Goose vodka better than Smirnoff at 6X the cost?

weebray - 5-10-2016 at 06:02 PM

Woody, Those products are way overkill for this little rental unit that gets some rain once in awhile. I do have a friend in Denver tho that has a leaky flat roof on a 7 story apartment bldg. He is trying to figure out what to do. I will forward your info. Gracias

chippy - 5-10-2016 at 06:54 PM

Quote: Originally posted by weebray  
I appreciate the responses but for a number of reasons torch down is not appropriate. We are not "paint" guys and were simply wondering what impermeabilizante is made of and if the various products were mas o menos egual. Is it necessary to spend 2X the $ for a name brand? It's like: Is Grey Goose vodka better than Smirnoff at 6X the cost?


You get what you pay for. Its all variations of vinyl paint.

weebray - 5-10-2016 at 07:01 PM

Chippy, That is not always true. Many times you can pay mucho for nada. That's the reason the question was posted. If it all has the same stuff in it then it should be pretty easy to see what it's worth according to the % of solids.

rhintransit - 5-10-2016 at 07:23 PM

I think it's a great question and look forward to some definitive answers.
By the way, I saw Comex advertising 30% off on impermeabalantes a few days ago but did not go in to check what brand or such.

BAJA.DESERT.RAT - 5-10-2016 at 07:28 PM

i had a leaky flat roof for over thirty years. had sears do it, a localk roofer do it, a private roofer do it, i've had over seven different roofs on it.

about ten years ago, a roofing contractor was referred to me and when he came out and saw the torchdown on it, he said you don't need a roofer, you need a waterproofing company.

he referred me to a company that does helipads on hi rise buildings.

it is a seven layer process that started with removing and stripping and repitching the roof with 3/4 " plywood, NOT PARTICLE BOARD.
then, a metal lathe that was stapled EVERY square inch. yup, it was noisy !

then, a light grade cement was poured over the roof. then, the next day, makita grinders to make sure it was level.

then, another layer of light grade cement and another makita sanding.

then, a layer of fiberglass cloth. and a epoxy coating.

then, another light cement layer and subsequent sanding. actually, it was a grinding.

then, some type of epoxy coating.

last coating was two coats of grey finish.

maybe a nine coat process ?

somewhere along the process, the workers took hatchets and cut into the surrounding wall so they could install Z-BAR. it's a metal flashing that slips under the hatcheted wall and lays flat on the decking. after wards, the hatcheted wall was plastered.

i had the contractor coordinate his roofing process with PELLA, the company that installed two sliding doors replacing the old bedroom sliders.

the roofing contractor had his workers install tar and roofing materials brfore the sliders were installed for a water tight fit.

after the sliders were installed, i had ADT re-install the alarm system into the new doors and and another sensor that allowed us to leave the slider open four inches with a foot latch to secure it open and un-budgeable. yes, my system was installed in 1986 and is hardwired.

after all the work was done. the contractor and i ran a hose at full pressure over the entire roofing system and sliders for about an hour. afterwards, he had some type of unit that he ran inside the living and dining room and hallway that seeks out and shows if there is a leak anywhere. NO LEAKS !

quite a process and haven't had a problem in ten years although the roof is due to be scrubbed and re-painted with their product again soon.

a friend of mine is a contactor and said it's a product called DEXATEC. not sure but i have the suppliers info if anyone would like to have it. if you do, i don't think this is a DIY product, just saying.

BIEN SALUD, DA RAT




Silicone based

bajaguy - 5-10-2016 at 07:35 PM

http://www.amazon.com/Gaco-Gr1600-Gacoroof-Silicone-Coating/...

surabi - 5-10-2016 at 08:23 PM

As to the OP's question- good impermealizante paint is not just thick paint. It's actually kind of rubbery (regular water based paints will wash up with water, oil based with thinner, but just try getting impermealizante out of a brush- it stays in clumps and you have to actually pull them out) and no matter how many coats you put, it has a transparency to it, unlike paint.
I have used Prisa 5 year in white- every year (sometimes 2) I powerwash and slap another coat on. I live on the mainland where it rains like stink for about 3 months straight and have never had a problem with leaks.
First coat should be thinned 10% with water, subsequent coats do not thin. Trick is not to put it on too thick- if you do, it can peel off. What you want are multiple thin coats with adequate drying time between each coat. Suerte.

surabi - 5-10-2016 at 08:25 PM

P.S. If you can get Sitka brand impermealizante, (Home Depot carries it) go for it. Higher quality than Prisa.

woody with a view - 5-11-2016 at 05:44 AM

We used to used a paint on new stucco houses called Elastomeric that was rubberized and would flex somewhat to conceal the inevitable cracking you get with stucco.

4x4abc - 5-11-2016 at 09:00 AM

I have used a number of different impermeabilizantes here in La Paz
they all allowed for some leakage
temperature differences are quite extreme and the roof expands and contracts
even with a membrane that creates tiny hairline cracks
they suck water in

then I found Impac 5000 at Home depot, with fibers, bucket contains 20% more than the regular 19 liter buckets (22.8 liter) - about $750 peso

2 coats - hasn't leaked since
we also walk on that surface and it's holding up really good
results were so impressive that I painted house and garage as well

could only find a link to the 6 year version (just a few bucks more)
http://www.homedepot.com.mx/comprar/es/mochis/impermeabiliza...

http://www.impac.com.mx/producto/IMPAC5000Fibratado

durrelllrobert - 5-11-2016 at 11:21 AM

Here in Punta Banda Kathleen Taormina's fiancee, Dan Eitein, did a wonderful job on my nearly flat roof using the white silicone roll on sealer. He first stripped off all the old hot mopped materials that was leaking at several low spots, repaired the low spots and put down two layers of the roll on.He also did the same on my neighbors house. Dan is a licsened, insured and bonded contractor in the states and can be reached (usually) at Kathleens house : 646-152-0900 or via email at bajakt@gmail.com

Alm - 5-11-2016 at 01:16 PM

When trailer people need to fix 15-20 year old membrane - without replacing it - they use very dense
Liquid Rubber. If the area isn't huge and roof profile isn't too difficult, it's a DIY job.

This one is for rubber-ish EPDM membrane. Can't say about TPO.

There are "impermeable paints" but they are just that - paints. Different density, different durability.

Silicone is notoriously incompatible with other sealants, AFAIK.

[Edited on 5-11-2016 by Alm]

UnoMas - 5-11-2016 at 05:33 PM

These are Elastomeric coatings and will bridge gaps up to 1/8 inch and have flexibility for expansion and contraction. Some come with ground ceramic in them for dropping interior temperatures and heat reflection. Silicon based coating may cause problems with adhesion down the road.
My experience is you will get better pricing and quality on roof coatings NOB than in Mexico. Most run 80-100 Sq. ft. per gallon when applied properly. You usually do get what you pay for when it comes to these type of coatings.
I think surabi meant Sika not sitka....Google Elastomeric roof coatings and look for what applies to your application. Many out there to choose from....Good Luck!:cool:

weebray - 5-11-2016 at 05:46 PM

Lots of great info out there but little to speak to my original question. I have used over the years several brands of product and the results have been about the same with whatever I used. I now think it does not matter what brand you use, Sika, Prisa, Pasa, Comex or b-tchen. It's all the same chit and you're only paying $ for the name. In the end it looks like a couple of buckets of whatever every three years + very little labor = beer thirty with no worries.

FWIW

akmaxx - 5-11-2016 at 06:08 PM

I stepped into Comex St. Rosalia recently with their %30 discount and it was 1079 pesos for five gallons of 5 year. I walked next door to Sherwin Williams who assured me their product was superior for 5 year and it was 700. I laid it on and it seems that it filled the cracks. Won't know until the hurricanes....For 6000ísh I could lay tarpaper and not worry at all but we all rolls the dice.

weebray - 5-12-2016 at 06:10 AM

Quote: Originally posted by akmaxx  
I stepped into Comex St. Rosalia recently with their %30 discount and it was 1079 pesos for five gallons of 5 year. I walked next door to Sherwin Williams who assured me their product was superior for 5 year and it was 700. I laid it on and it seems that it filled the cracks. Won't know until the hurricanes....For 6000ísh I could lay tarpaper and not worry at all but we all rolls the dice.


You make my point. Everyone says their stuff is much better but no one backs it up with facts. Why is it better? I have seen no proof - all the 5 and 7 year stuff seems the same. BTW 5 and 7 year means absolutely nothing, in fact none of it lasts more than 3. Here in La P a cubeta is about half of what it costs you in SR.

4x4abc - 5-12-2016 at 10:04 AM

if you are dealing with quality products, the density will give you answers about durability (the cheaper ones have more water)
http://www.homedepot.com.mx/comprar/es/torres/impermeabiliza...
http://www.homedepot.com.mx/comprar/es/torres/impermeabiliza...
http://www.homedepot.com.mx/comprar/es/coapa-del-hueso/imper...

but never trust advertising (a different form of lying) - get the specs

weebray - 5-13-2016 at 06:15 PM

Quote: Originally posted by 4x4abc  
if you are dealing with quality products, the density will give you answers about durability (the cheaper ones have more water)
but never trust advertising (a different form of lying) - get the specs


Suspicions confirmed. It's all the same stuff with more or less water in it. The trick is in determining the % of solids. I think it's really a mute point tho. I've never found anything that lasts more than 3 years. El sol tan fuerte.

monoloco - 5-14-2016 at 12:41 PM

If it is a concrete roof, the first thing to do is to open up any cracks with a grinder and a diamond wheel so they are 1/8-1/4" wide and 1/4-1/2" deep and fill them with polyurethane caulking, (you can buy it at Sayer or Comex. It's like 3M 5200 marine sealant) then apply whatever roof coating you choose to use. Roof coating alone does a really lousy job of sealing cracks but that polyurethane sealant is bombproof.