Tile grout issues

[Tom JE]

Hi All,

I have previously used the ready mixed tile grout around my house with no real problems. The only issue I had was that on darker grouts the colour has faded in areas that get wet a lot (like the bathroom floor - I have patches just by the bath where the grout has gone from grey to almost white).

This weekend I tried a powdered grout, in 'charcoal' (Unibond) over my new kitchen floor which was a lot easier to apply. However, I have noticed that now it has dried the colour is really different across the floor from black to light grey. Also, the bits left in the tub I used to mix it seem a bit crumbly although solid where applied. I mixed it up as per the instructions.

Any ideas as to what I did wrong? Is this a common issue or have I just used a bad brand?

Thanks,

Tom

 

[Paul C.]

Being crumbly and patchy in colour would normally imply an issue with the mixing. You say you have mixed it as per the instructions but too much water is the most common cause of crumbling grout and efflorescence, meaning the salt contained in the cement is dissolved and separated when water is added. When the grout is mixed, applied and starts to dry, the moisture disperses and carries the salt to the surface. Its a very common problem with some grouts but it should be fixable.

Buy some LTP Grout Stain remover, some rubber gloves and a scrubbing brush. Apply the solution neat to the affected areas and scrub it for a couple of minutes. You will notice it start to fiz showing that it is having an effect. Make sure you have a bucket of clean water to hand and rinse as you are going along.

After a further rinse and allowing it to dry, you should see an improvement. If the problem remains, I'd question the quality of the grout. If as a last resort you need to reapply the grout, go for a bag of Mapei Ultracolor Plus. This is guaranteed as efflorescence free, has a built in water repellent and is impervious to nuclear blasts. Best grout I've ever used. Be careful though. it sets pretty quick.

 

[Tom JE]

Thanks Paul, that makes perfect sense now you've explained. I'll get on the case later today.

Cheers,

Tom