# Forum Home Renovation Waterproofing  Waterproof Membrane strength/adhesion problems Betta Gripset

## bearmatt

Hi,
Earlier today I waterproofed my home bathroom reno and I am quite concerned by the membrane adhesion to the new wall (new Villaboard)
I was scraping an adjacent joining area of old wall (scraping off paint) and noticed that the membrane has very poor adhesion to the villaboard and seems to lift easily (yet it stuck to the old wall like superglue)
The prep was:
- day 1 afternoon - wiped down with water 
- day 2 morning - sealed with 1 coat of  betta prep coat primer (as per instructions)
- day 3 - applied 2 coats membrane 
It has only been maybe 4 hours. It is very flexible, but I dont see how it will hold up tiles ? Has any had any experience of this, or am I worrying about nothing ?I will obviously speak to Gripset and see what they reckon went wrong (if anything) 
Thanks 
Matt

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## intertd6

This should be in the waterproofing section for a better response.
inter  _- done_

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## bearmatt

Well...Betta Gripset (ex Bunnings) is owned by Bondall 
Their advice was sincere but guarded and sketchy to say the least. 
Their technical contact did not know what Villaboard or Fibro was, nor how dense it was. I advised that it is slightly porous yet is quite dense. 
He then suggested that maybe I should have used their other primer called Superprimer (packaging indicates it is suitable for Steel, Plastics, Glazes, old tiles etc)
I asked -  would it be best to use two coats of Superprimer or one, he was reluctant or unable to answer. 
So, In conclusion:
The PrepCoat primer by Betta Gripset is complete junk and seems to serve little purpose. It is certainly too weak as a film strength to provide any noticeable difference in using or not using it.
It is fair to say that the resilience and pull off strength of the Under Tile membrane is multiple times better over old paint.
So now I have 10-11L of Under Tile Membrane to finish the rest of the bathroom with and am left wondering what to do.
I suspect that many a membrane has been installed across the country and is just barely hanging in place, ready for some rouge moisture or movement to complete its failure.
I will remove the membrane and start again. 
Matt

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## phild01

Before throwing it away, in a test area, try diluting the membrane 50:50 with water and use that as a primer.

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## METRIX

> Hi,
> Earlier today I waterproofed my home bathroom reno and I am quite concerned by the membrane adhesion to the new wall (new Villaboard)
> I was scraping an adjacent joining area of old wall (scraping off paint) and noticed that the membrane has very poor adhesion to the villaboard and seems to lift easily (yet it stuck to the old wall like superglue)
> The prep was:
> - day 1 afternoon - wiped down with water 
> - day 2 morning - sealed with 1 coat of  betta prep coat primer (as per instructions)
> - day 3 - applied 2 coats membrane 
> It has only been maybe 4 hours. It is very flexible, but I dont see how it will hold up tiles ? Has any had any experience of this, or am I worrying about nothing ?I will obviously speak to Gripset and see what they reckon went wrong (if anything) 
> Thanks 
> Matt

  So how long did you leave between primer and membrane ? it is best to apply the membrane withing a hour of primer, if you leave the primer for 24 hours, it's recommended to wipe it down and reapply (other brands) so I don't see why this product would be any different to others out there. 
I was given some of the gripset membrane to use on a job and I didn't like it, I used the Super Primer and it was fine, the membrane stuck to the vilaboard fine but I found the membrane to thin when applied in the same fashion as something like Davco K10 Plus or Crommelin product. 
I would leave it for 24 hours and try again, if it peels off easily then you have a problem I would take it up with gripset, peel it off and start again with a different product, probably return the product to Bunnings explaining you have spoken to the manufacturer and feel it is faulty, and they can return it to them. 
Davco PrimeX (Red) or Davco Ultraprime (Blue) is what I use and haven't had issues with these both are designed for Villaboard as well as other substrates as stated in their documentation.
Then K10 Plus or Cromellin shower Waterproofer, both perform really well and have not had the problems as you show, interestingly the cromellin does NOT require a primer. 
Also I have also found Parex Technical Support to be really good, oh and Parex know what Villaboard is  :Rolleyes:

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## bearmatt

> So how long did you leave between primer and membrane ? it is best to apply the membrane withing a hour of primer, if you leave the primer for 24 hours, it's recommended to wipe it down and reapply (other brands) so I don't see why this product would be any different to others out there...

  Metrix - thank you soo much for your assistance,.
Primer to membrane was probably only 12 hours. 
Manufacturer (Bondall) tech guy barely new anything about the product, let alone how best to tackle my questions - except to say that I should maybe have used another primer - they are a joke.
Thanks phild01 for the suggestion - I have tested a watered down version of the primer and it is much the same. I also tested a heavy coat of the Superprimer and a light coat of their SuperPrimer.
In every test case so far - it seems as though the failure (as pictured) is at the Gyprock - it easily peels off the wall like a bandaid off your finger
Do you think another membrane will be OK with the Gripset SuperPrimer underneath.
Thanks again
Matt

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## METRIX

> Metrix - thank you soo much for your assistance,.
> Primer to membrane was probably only 12 hours. 
> Manufacturer (Bondall) tech guy barely new anything about the product, let alone how best to tackle my questions - except to say that I should maybe have used another primer - they are a joke.
> Thanks phild01 for the suggestion - I have tested a watered down version of the primer and it is much the same. I also tested a heavy coat of the Superprimer and a light coat of their SuperPrimer.
> In every test case so far - it seems as though the failure (as pictured) is at the Gyprock - it easily peels off the wall like a bandaid off your finger
> Do you think another membrane will be OK with the Gripset SuperPrimer underneath.
> Thanks again
> Matt

  Matt you never water down the primer, but you can use a 50:50 water to membrane as a substitute for the primer. 
You now mention Gyprock, is it Gyprock or Villaboard ? 
You shouldn't have a problem with another membrane on top of another primer, but the various manufacturers would not warrant their product if you did this as they can say there was an incompatibility and rightly so as each company spends a lot of money on R&D ensuring the product they make is compatible.  
You need to determine if it's the membrane letting go of the primer, or the primer letting go of the villaboard. 
This is where the Davco stuff is good as it has a coloured dye in it, the gripset stuff dries clear, if you spray some water onto where the membrane has pulled off you should be able to tell if the primer is still on there as the water will form droplets, if the primer has removed the water will soak into the villaboard.

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## phild01

> Thanks phild01 for the suggestion - I have tested a watered down version of the *primer* and it is much the same. I also tested a heavy coat of the Superprimer and a light coat of their SuperPrimer.

  ...no!   

> Before throwing it away, in a test area, try diluting the *membrane* 50:50 with water and use that as a primer.

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## phild01

I have never bothered with wet area plasterboard but if it is resistant to water, how well does a water based membrane on it compare with villaboard!

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## bearmatt

Thanks again Metrix for the advice.
1. It was suggested to me to test a watered down product - I presume with the view to better penetration.
2. Definitely Villaboard (my typo).
3. In all trials it seems that the flexibility and adhesion of the membrane and primer is good. In my test cases, the gyprock seems to be failing as evidenced by the light brown/pink on the back of the membrane. 
4. I will change to either Crommelin or Davco (on top of Gripset Superprimer) and let you know the results
Thanks
Matt

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## bearmatt

Yes, interesting question. How can any waterbased product significantly adhere to a surface that is resisting water.
The villaboard is proving to be a nuisance, albeit it is slightly porous it seems to give up its surface easily to a membrane pull test

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## bearmatt

> I have never bothered with wet area plasterboard but if it is resistant to water, how well does a water based membrane on it compare with villaboard!

  Yes, interesting question. How can any waterbased product significantly adhere to a surface that is resisting water.
The villaboard is proving to be a nuisance, albeit it is slightly porous it seems to give up its surface easily to a membrane pull test

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## wspivak

Hi Bearmatt, 
It is possible you may have a sub-standard quality batch Villaboard.  What appears to be happening is the top layer of the villaboard is completely delaminating from the layer below it.  This isn't a primer/membrane issue (as the membrane is quite obviously stuck hard enough that it is pulling the top layer of villaboard off) - and I'll be very surprised if any other product will fare better under the circumstances. 
Where did you buy the villaboard and do you know who the manufacturer of it is?

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## bearmatt

Thanks wspivak,
Yes you are correct that the Villaboard is letting go.  It is James Hardie branded. I purchased a variety of sized sheets which would have come from different production runs.
I read an web article by the Australian Institue of waterproofing that said 90% of failures was due to poor workmanship - so not sure what I did wrong yet but I shall figure it out.
I don't think the problem is really with Gripset membrane. It seems as though using the Superprime (vs the Prepcoat) is better as it has a much stronger film strength than the PrepCoat primer, which means the combined resilience of the membrane and primer is much better - but again they both pull off the wall like an easy bandaid - god knows how its supposed to hold up tiles for 20 years.....
The easy fix is to stop testing it and stop pulling it off.. 
I have a few experiments running in the bathroom with regard to different membranes K10 + Gripset vs primer applications.

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## phild01

Still think the 50:50 membrane as a primer should get a show in the testing.

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## bearmatt

> Still think the 50:50 membrane as a primer should get a show in the testing.

  Hi phild01,
Thanks for pointing out that I didn't read your initial post correctly. I had a chuckle..
Your suggestion of 50/50 Membrane as a primer coat is being tested and is on the wall. I will recoat with 2 coats of membrane tomorrow.
Running out of walls though.
Matt

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## METRIX

> I have never bothered with wet area plasterboard but if it is resistant to water, how well does a water based membrane on it compare with villaboard!

  It does fine, same as applying undercoat / paint to it, the products have binders, polymers and resins and all sorts of magic components which are designed to hold onto porous or non porous substrates with or without undercoats / primers depending on the product. 
Think about how a water based membrane works, out of the bucket you can wash it away with water, once it dries it's impervious to water. 
When Scyon was first released there were problems with the membranes sticking to it because the primer's were not made to suit whatever was on the surface, this is where products like PirmeX came from to work with the newer generation of substrates.

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## phild01

> When Scyon was first released there were problems with the membranes sticking to it because the primer's were not made to suit whatever was on the surface, this is where products like PirmeX came from to work with the newer generation of substrates.

  Makes me wonder if that is why I had problems with my old Scyon and peeling membrane.  Did use the red PrimeX but found diluting the Crommellin gave the better result for adhesion. 
I do believe water penetration into the Scyon was the causative factor for the peeling membrane though, having been exposed to weather for about 2 years, before tiling.

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## METRIX

> Makes me wonder if that is why I had problems with my old Scyon and peeling membrane.  Did use the red PrimeX but found diluting the Crommellin gave the better result for adhesion. 
> I do believe water penetration into the Scyon was the causative factor for the peeling membrane though, having been exposed to weather for about 2 years, before tiling.

  I would say the exposure for 2 years was the cause rather then the primer, I have used PrimeX on many Scyon floors and had no issues

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## phild01

> I would say the exposure for 2 years was the cause rather then the primer, I have used PrimeX on many Scyon floors and had no issues

  I will agree as it only peeled in the most exposed area. I tried to do the repair using PrimeX but it peeled back again, by then I resorted to 50:50 but it could be said the substrate was improving with each attempt...don't know!

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## edwardrjones

Did you find any solution to this? I am in the same boat. I primed villaboard and ceramic tile underlay with Gripset Prep Coat & Additive then applied Gripset Waterproofing Membrane. Followed the instructions on the Primer and Membrane exactly but it has not stuck. It can be peeled away from the wall easily. 
I have no idea what the cause is

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## wspivak

Ok guys, after consulting with the tech experts at Gripset and several existing customers - this is an ongoing issue with most composite materials.  The issue is that the composite materials such as villaboard will lose the top layer when subject to peeling of an adhered product such as a waterproof membrane. 
However - the pull tests are what is important and peeling "tests" are not something that should be attempted as the above issue will occur almost all the time. 
In essence, you'll find the adhesion with respect to pull tests are within specifications and are perfectly safe for tiles as long as the surface was cleaned & primed properly. 
Hope that helps.  Give us a call if you have any further queries, we're more than happy to assist.

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## Timber21

> So how long did you leave between primer and membrane ? it is best to apply the membrane withing a hour of primer, if you leave the primer for 24 hours, it's recommended to wipe it down and reapply (other brands) so I don't see why this product would be any different to others out there. 
> I was given some of the gripset membrane to use on a job and I didn't like it, I used the Super Primer and it was fine, the membrane stuck to the vilaboard fine but I found the membrane to thin when applied in the same fashion as something like Davco K10 Plus or Crommelin product. 
> I would leave it for 24 hours and try again, if it peels off easily then you have a problem I would take it up with gripset, peel it off and start again with a different product, probably return the product to Bunnings explaining you have spoken to the manufacturer and feel it is faulty, and they can return it to them. 
> Davco PrimeX (Red) or Davco Ultraprime (Blue) is what I use and haven't had issues with these both are designed for Villaboard as well as other substrates as stated in their documentation.
> Then K10 Plus or Cromellin shower Waterproofer, both perform really well and have not had the problems as you show, interestingly the cromellin does NOT require a primer. 
> Also I have also found Parex Technical Support to be really good, oh and Parex know what Villaboard is

   
Hi Metrix
saw this reply to a post about waterproofing and thought you might be able to help with my query.
The builder renovating my bathroom uses Davco PrimeX primer and Davco K10 Plus waterproofing membrane. In the joints he says he uses Sikaflex Pro polyurethane as a sealer and bondbreaker. He doesn't use the Davco K5 bondbreaker silicone product. The builder doesn't use any tape on the corners/joints.
I contacted Sika Tech Support who said the Sikaflex Pro cannot be used as a bondbreaker and that silicone must be used. Davco told me that a bandage must be used, the K10 Plus data sheet states a polypropylene/polyethylene tape must be used, yet the Davco 'How To Waterproof' video omits bandage with the membrane being applied directly over the bondbreaker. 
I am completely confused about what to believe. If even Davco are inconsistent with instructions, how do I proceed so I can be confident in the application? 
You seem familiar with the Davco system. Would you explain step by step what you do? 
Thanks
Timber21

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## phild01

When I last used K10, silicone was the bond breaker recommendation, and IIRC masking tape would you believe!

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## METRIX

> Hi Metrix
> saw this reply to a post about waterproofing and thought you might be able to help with my query.
> The builder renovating my bathroom uses Davco PrimeX primer and Davco K10 Plus waterproofing membrane. In the joints he says he uses Sikaflex Pro polyurethane as a sealer and bondbreaker. He doesn't use the Davco K5 bondbreaker silicone product. The builder doesn't use any tape on the corners/joints.
> I contacted Sika Tech Support who said the Sikaflex Pro cannot be used as a bondbreaker and that silicone must be used. Davco told me that a bandage must be used, the K10 Plus data sheet states a polypropylene/polyethylene tape must be used, yet the Davco 'How To Waterproof' video omits bandage with the membrane being applied directly over the bondbreaker. 
> I am completely confused about what to believe. If even Davco are inconsistent with instructions, how do I proceed so I can be confident in the application? 
> You seem familiar with the Davco system. Would you explain step by step what you do? 
> Thanks
> Timber21

  A bond breaker as it's name suggests breaks the bond between two surfaces, in the case of waterproofing you want to keep the bond between the wall and floor junctions free to move as the building expands and contracts, these movements are only small, but without a correct bond breaker these critical junction points can be damaged resulting in water leaking through them.   
Products like Sikaflex Pro and 11FC are NOT true bonbreakers and should not be used as one, these products are Sealant / Adhesives, this means when you apply the membrane over the top of them the membrane will stick permanently to these products. 
A caulked on bond breaker is a Neutral cure silicon based product, the neutral cure is important as lots of cheap silicons are acidic cure and these should not be used as bond breakers as the acid cure can cause incompatibility issues with membranes. 
There is no need to use Davco K5 but this product does dry quick which allows the job to continue, you can use any silicon product as long as it's Neutral cure, as a basic rule if any product says on the label paint over it should not be used as a bond breaker, products that are silicon based are non paintable. 
To use or not to use tape is another discussion, I would always recommend the use of tape as it acts as a reinforcement for the critical joins.
I stopped using silicons as bondbreakers years ago, and have been using tapes with inbuilt bondbreakers as they are easy to apply, you don't have to stuff around with silicon and wait for it to dry, and mainly because they work. 
I only use the gripset Elstoproof B50 taping system this is basically a foolproof system to guarantee waterproofing, the commercial system is Grey and sold in larger quantities, Bunnings do a retail version which is the same product it comes in Blue or green. 
They have factory made internal / external corners which are waterproof from the factory.   https://gripset.com/products/elastoproof-b50/  https://www.bunnings.com.au/waterpro...betta_p0960177

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## Timber21

Thanks Metrix 
I think I will ask the builder to just use the K5 as that will help secure the Davco warranty. 
So, for the tape, could I use the Crommelin reinforcing tape without bondbreaker over the K5?
Am I right in thinking that the membrane gets painted on the joint (after the K5 is dry), then the tape gets smoothed over the top and into the membrane so that it sticks and then the fabric is painted over again with the K10 membrane so that it is fully embedded?

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## OneZero

> but I found the membrane to thin when applied in the same fashion as something like Davco K10 Plus or Crommelin product.

   I too found this compared to Bostic and K10+

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## Timber21

Thanks to all for your input 
I have an update...despite the information in the Davco K10 data sheet and the Tech Rep from Davco writing that I need to follow/apply products as per the data sheet, I was able to speak with the same rep by phone to clarify and he stated definitively that 
1. Davco K10 used to be applied with a Davco Polyurethane sealant acting as a bond breaker in the joint
2. The Davco polyurethane is no longer manufactured so now Davco use K5 in its stead.
3. The Sikaflex Pro polyurethane is definitely suitable/compatible to be used as sealer and bondbreaker with the Davco K10 Plus membrane (provided this in writing). He said, in general neutral cure silicones are used but the Davco water-based polyurethane membrane is a bit different and will not stick to the SikaFlex just as it will not stick to polyethylene or polypropylene.
4. There is no need to use tape unless the gap is wide, in which case a cloth filled adhesive gaffer tape will suffice to provide enough bond breaking for the membrane. The use of tape is a discretion based on the gap size. (Guess this is best left to the professionals)
5. The gaffer tape does not reduce the class of the membrane but reinforcing fabric may be different story. Got information from the Australian Institute of Waterproofing which stated "The AS3740 nominates the sealant to be placed in the corner joint, a 'bond breaker' can be completed with a Class 2 membrane with a tape, or with a Class 3 membrane without a tape. Find out what Class of membrane is being used and you have your answer."
5. The Davco tech support guy discouraged the use of the Crommelin polyester fabric as it may not be compatible with the Davco membrane
6. Davco Tech Support says use the products in the data sheet because they are in the data sheet. Doesn't mean have to use the Davco K5 product. Other products can be substituted. In any event will ask my builder why he prefers the SikaFlex PRO. 
Seems like my builder knows what he is doing  :brava:   Fingers crossed.
This forum is a great 'go to' for discussion and I have learnt more about waterproofing than I probably should. It has been a confusing ride!!  :Doh:

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