Hi, I have just grouted my newly tiled bathroom walls with Mapei Ultracolor Plus. Problem is I don't seem to be able to get a very smooth mix, no matter what I have tried it still remains gritty.

I have followed instructions (obviously) but also tried a few variations (slightly wetter, slightly drier etc.) and just can't seem to get it smooth.

Any tips for the perfect grout mix?

are you using an electric paddle mixer or doing it by hand

Doing it by hand, I had read that using a paddle introduces too much air and may result in air bubbles forming inside the grout?

paddle on a slow setting is best mix once then let it stand for5 minutes then re mix at slow speed

Originally Posted by jazzhands

Doing it by hand, I had read that using a paddle introduces too much air and may result in air bubbles forming inside the grout?

Mapei do advise the use of a mechanical stirrer.. i,e paddle mixer.. read the instructions on the bag.. or try these>>>> Mapei ultra colour plus ...how to use.

Is it gritty because it has gone off or has got damp? I would try a new bag

if you mean when applying the grout in between tiles then, you can polish with a sponge.

Ultracolour is a grity grout and many people say that it is harder than other grouts to work with. Ultracolour when mixed correctly is a rather heaxy mix in comparison to Bal for example. For this reason I use Ultracolour of floors but recently have started using Bal grout on walls as I feel its easier to work with on walls than ultracolour.

Tools for mixing should not realy be operated higher than 700rpm so select your mixing drill based on this. Most power drills will operate upto a few thousand rpm which would be too fast. As already suggested consider purchasing a proper mixing drill and paddle.

When using more or less water than recommended be sure not to over do it as incorrect ratios will weaken the mix and the grout could fail at a later date.

Thanks guys, I do have one of those paint paddles a few different drills with varying speeds so will give that a try next time. Won't be too long because I've got a kitchen and utility wall and floor to do in the next few weeks.

Incidentally I am putting down travertine effect ceramic tiles in the kitchen but what is the view on grout colour - will white end up dirty within days so be better going for a colour (beige/cream)? Don't really think grey will go with tiles due to colour though.

I agree with tfs, BAL grout has a longer bucket time and is easier to smooth, you do need to be super fast with the mapei. As for grout colour on travertine/travertine effect go for BAL wide joint limestone (or similar, other brands are available!) very complimentary colour to this tile and does not show the dirt like white or ivory will.

Originally Posted by jazzhands

Thanks guys, I do have one of those paint paddles a few different drills with varying speeds so will give that a try next time. Won't be too long because I've got a kitchen and utility wall and floor to do in the next few weeks.

Incidentally I am putting down travertine effect ceramic tiles in the kitchen but what is the view on grout colour - will white end up dirty within days so be better going for a colour (beige/cream)? Don't really think grey will go with tiles due to colour though.

I'd be using Ultracolor Plus Jasmine for those tiles on the floor if it was me.