Impey membrane incompatible with Epoxy grout

[ojtiler]

All,

This isn't a query, just a brief summary of a situation I got myself into which you might want to avoid! In my wetroom project, I bought the tanking membrane right at the start of the job - I selected the Impey membrane as it looked relatively easy to install.

To avoid having to re-grout my wetroom in a few years, I decided to go for Epoxy grout, to make an exceptionally durable (and waterproof) finish between the tiles.

The thing I overlooked was that, as well as the Impey membrane being incompatible with silicones etc, Impey also recommend that epoxy grouts should not be used!!!!

Having taken technical advice from both Impey and BAL (the manufacturer of the epoxy grout), the solution I have implemented is to ensure that the epoxy does not actually directly contact the membrane. On the floor I am using SLC, so there is a nice 4-5mm protective layer over the membrane in that region... On the walls, I am ensuring I get a solid bed adhesive layer behind the tiles and will also put a layer of normal (cementitious) grout on the joints first (about 4mm thick), before grouting over again with the Easy poxy.

A lot of work, but the only way I feel happy that the membrane is going to be in safe.!

I think if I had my time again I would go for a different mambrane!!

Just thought I would post my experience here, in case anyone is considering going the same way.

 

[DHTiling]

You would need to be having a solid bed of adhesive anyway.. so the grout will not be in contact with the membrane..

 

[ojtiler]

Thanks, Dave.

I should have explained I'm using solid bed on all wall tiles....I just feel a bit safer if I apply a bit of normal grout first - as I can't rule out the possibility of the odd small void in the adhesive.

 

[SteveyJ]

Probably really obvious but Just a thought on how you mix up the SLC - if you pour it over the impey tray you may lose all your Impey falls, so might be worth doing the tray area in SPF with a trowel if you want to protect it that much?? Ive done a load of Impey Trays with their membrane and never had any issues - think its great. I always use Ardex Grout and always seems to work well.

Steve

 

[Ajax123]

Why is epoxy not compatible?? Can't see any technical reason why I would be??

 

[Impey Showers]

Hi,

Impey Tilesafe is a rubberised bitumen based product which reacts with certain chemicals found in silicone, solvents and epoxy.
It causes the Tilesafe to breakdown into a liquid and therefore destroys its waterproofing qualities.

Tilesafe compatiblle adhesives and grouts must be cement based (cementitious) single part, mixed with water, flexible and waterproof, Latex additives are acceptable as long as the adhesive or grout is mixed with water. Bal,Mappei, Granfix, Ardex and Unibond all manufacture suitable products.

 

[Concrete guy]

Why is epoxy not compatible?? Can't see any technical reason why I would be??

That question popped straight into my mind and behold, the answer is in the next post!