Crumbling Grout

[Tiling Newbie]

After feeling very pleased with myself for tiling my bathroom floor a couple of weeks ago, I have now noticed that the surface of some grouting lines are beginning to crumble. Does anyone know what could be causing this? and is it enough to rake out the offending area and re-grout?

 

[JohnD]

Is it on a wooden floor that could be moving? A ply subfloor is best in a bathroom.

Also the grout and adhesive for wooden surfaces is not the same as for walls and concrete floors, as they move more.

 

[Moz]

Tiling Newbie
did you use one of the DIY sheds grout tub mix ... ?

awful stuff ...

 

[Tiling Newbie]

It is a wooden floor. The existing build up is chipboard over the joists then a layer of hardboard, I put down a layer of 5mm ply on top of that.

I used a unibond 'tile on floors' quick grout and mixed it myself. It does not specify a floor type on the bag, but I was told by the expert in B&Q that it would be fine for wooden floors. hmm...

 

[nellyb]

Seems like another good example of why you shouldn't patronise places like B&Q. The staff don't know their a@@e from their elbow!

 

[Moz]

Tiling Newbie

never use the DIY sheds , go to topps tiles or a local tile shop ,