Waterproof addy + grout - TilersForums.co.uk | Tile Forums

macten · 26-02-2008

I was taught that the only true waterproof addy/grout was epoxy.
Taught the difference between water-resistant and water-proof.
My question is why do most manufacturers state waterproof on their packaging?
Can imagine tricky situations in the future with customers when I explain the benefits of tanking etc.. and the customer shows me their 'waterproof' addy + grout.
What should you say? They're lying?
Or have I got this wrong?

**Dave** · 26-02-2008

hi macten....

You are right in saying epoxy is the only true waterproof grout....

As for manufactures stating there other grouts are waterproof , which brand was it mate..?...

BAL grouts ( which i use ) just state water resistant.......

BAL Superflex Wall Grout

A brilliant white, water & frost resistant cementitious wall tile grout with built-in admixture to give increased flexibility and high bond strength. Suitable for grouting porcelain, marble, natural stone, glass and ceramic mosaics, glazed and fully vitrified tiles. BS EN 13888 CG2 Grout.

macten · 26-02-2008

Almost all DIY brand stuff states it.
Just going through some leaflets and have come across:
BAL supergout
Bal tile + grout
Dunlop large format + natural stone adhesive
Dunlop fix 'n' grout
Dunlop ready mixed grout with microban
All these state waterproof.

**Dave** · 26-02-2008

BAl super grout and BAL tile and grout do say waterproof yes......so i can assume they are...have you had probs with them particular ones mate......?.

Me personally if i wanted water tight grouting then it would have to be epoxy all the way......i think the other 2 are just diy types...but never used them so cant really comment......maybe one of the bal guys might see this thread and chuck in some advise.........

**grumpygrouter** · 27-02-2008

My understanding of "waterproof" regarding adhesives and grouts is that the product doesn't breakdown when in contact with water. It doesn't mean that it will protect the surface underneath from the water just that it will not deteriorate. If they were waterproof in the strictest sense than there would be no need for tanking products which are waterproof.

As an example, PVA breaks down when contacted with water and tries to revert to it's original state, this being the reason why it is not suitable for tiling. Water can penetrate through the grout and adhesive to the PVA and cause problems, even though the addys/grouts may be waterproof, if you see what I mean.

Grumpy

**sWe** · 27-02-2008

Correct me if I'm wrong, but as far as I know, cement based addy/grout can't be waterproof, just resistant, which is another way of saying "waterproof to a degree".

It's kind of like those expensive outdoors/wilderness clothes/shoes which are marketed as being able to "breathe", and that they're "waterproof", all in the same sentance; It's an oxymoron.

If it's waterproof, then it doesn't "breathe", because it can't, as the damn pores are fused shut.

Same goes for cement based compounds. If there is cement, there will be some form of capillary action, which is kind of like the cement version of breathing.

Even most tanking products are only waterproof to a degree, and that degree is waterpressure. A system meant for a domestic bathroom can probably stand anything you can throw at it, in a domestic bathroom. It, likely however, wouldn't stay proof at the bottem of a 10m deep swimming pool for very long.

**sWe** · 27-02-2008

Quote:

Originally Posted by grumpygrouter

My understanding of "waterproof" regarding adhesives and grouts is that the product doesn't breakdown when in contact with water. It doesn't mean that it will protect the surface underneath from the water just that it will not deteriorate. If they were waterproof in the strictest sense than there would be no need for tanking products which are waterproof.

As an example, PVA breaks down when contacted with water and tries to revert to it's original state, this being the reason why it is not suitable for tiling. Water can penetrate through the grout and adhesive to the PVA and cause problems, even though the addys/grouts may be waterproof, if you see what I mean.

Grumpy

Good angle mate, probably spot on. Perhaps it's a marketing trick meant to fool the unknowing?

macten · 27-02-2008

Thats the problem though Grumpy.
My understanding of waterproof is that it is just that.
Waterproof and water resistant are 2 different things.
So why do the same manufacturers eg BAL and Dunlop describe either water resistant or water proof depending on their product when they mean only water resistant.
May ring the tech lines and let you guys know their answer.