Phantom Patches on Mapei 112 Grout

[dilby]

Hi all - I've just done a DIY tiling job on new tiles using Mapei medium grey grout ultracolor 112 for the grout. I've used Mapei Ultracolor for loads of projects but never that exact shade, but have never had a problem before. Frustratingly it's dried with really inconsistent colour with some really dark patches. Next to those patches it seems really light so I'm assuming the pigment has for some reason separated out. I found this post here with a similar problem with the exact same colour so I'm wondering if there's a known issue with the 112?

It'd be great to know some suggestions of what's gone wrong, but at either rate I need to sort it and really don't fancy raking it all out. I'm considering trying a light top up with another go; risky of flaking too high?

Thanks

 

[Dave]

Morning, were the joints clear of adhesive, as in consistent depth. ? , this can result in varying shades of drying and also if you leave excessive water when washing off can result in polymers laying in the joints and giving a very patchy finish.

 

[dilby]

Morning, were the joints clear of adhesive, as in consistent depth. ? , this can result in varying shades of drying and also if you leave excessive water when washing off can result in polymers laying in the joints and giving a very patchy finish.

Thanks for the reply. Yeah that should be all consistent. I'm not aware of any excessive water either; didn't add any to the mix or surface. Do you reckon i can try adding a thin coat of grout to the top or am I going to need to scrape out? Hoping because its fresh i can get away with a thin coat

 

[Dave]

Thanks for the reply. Yeah that should be all consistent. I'm not aware of any excessive water either; didn't add any to the mix or surface. Do you reckon i can try adding a thin coat of grout to the top or am I going to need to scrape out? Hoping because its fresh i can get away with a thin coat

Normally need a 3mm depth to hold. An alternative is colour the joints with mapei fuga fresca. Very simple to use. This video isn’t in English but you’ll get the drift of how to use it.

 

[dilby]

Normally need a 3mm depth to hold. An alternative is colour the joints with mapei fuga fresca. Very simple to use. This video isn’t in English but you’ll get the drift of how to use it.

Wow thanks David. This could save me a headache or two; was aware of the white grout pens but didn't know mapei did their colours in the equivalent. Do you know long lasting this stuff is? Trying to balance doing the job right with the ballache of removing grout in a kitchen diner which is 30m2!

 

[Joe8189]

Hi all - I've just done a DIY tiling job on new tiles using Mapei medium grey grout ultracolor 112 for the grout. I've used Mapei Ultracolor for loads of projects but never that exact shade, but have never had a problem before. Frustratingly it's dried with really inconsistent colour with some really dark patches. Next to those patches it seems really light so I'm assuming the pigment has for some reason separated out. I found this post here with a similar problem with the exact same colour so I'm wondering if there's a known issue with the 112?

It'd be great to know some suggestions of what's gone wrong, but at either rate I need to sort it and really don't fancy raking it all out. I'm considering trying a light top up with another go; risky of flaking too high?

Thanks

Hey Dilby
The thing with any Mapie grout, has a lot to do with the mixing. In order to get it uniform you need to shake the bag to mix the powder before you add the water. I also found that when you mix it's best to do about 3 mins mixing then let it stand for a minute or two, then mix again, stand again, then a final mix of another 3-4 mins. Also when you come to remove excess grout try using a large scrubbing pad rather than using a wet sponge. They come in Blue or the softer white pads 6x3 a bit like a large scotch pad. (Cant remember the trade name) Use the blue pad first to remove the grout when its semi dry. Only rub off lightly over the joints.
When the grout is a bit dryer then use the white pad to remove the drier powder. Finally sponge lightly, then sponge in the direction of the joints to smooth the grout to a nice finish. When dry I use one of those fibre cloths to polish the tiles. Also try to do 1 area at a time.
With regard to re grouting over the existing, I wouldn't. Go with Dave's suggestion to use the Mapei product.

 

[Dave]

Wow thanks David. This could save me a headache or two; was aware of the white grout pens but didn't know mapei did their colours in the equivalent. Do you know long lasting this stuff is? Trying to balance doing the job right with the ballache of removing grout in a kitchen diner which is 30m2!

One of my customers changed the colour of they’re grout couple yrs ago from grey to charcoal and its still looking great.

 

[dilby]

One of my customers changed the colour of they’re grout couple yrs ago from grey to charcoal and its still looking great.

Bloody hell this sounds line a winner. Thanks so much!

 

[Nicky Shepherd]

Hi all - I've just done a DIY tiling job on new tiles using Mapei medium grey grout ultracolor 112 for the grout. I've used Mapei Ultracolor for loads of projects but never that exact shade, but have never had a problem before. Frustratingly it's dried with really inconsistent colour with some really dark patches. Next to those patches it seems really light so I'm assuming the pigment has for some reason separated out. I found this post here with a similar problem with the exact same colour so I'm wondering if there's a known issue with the 112?

It'd be great to know some suggestions of what's gone wrong, but at either rate I need to sort it and really don't fancy raking it all out. I'm considering trying a light top up with another go; risky of flaking too high?

Thanks

HI I have the exact same problem but its with limestone colour Mapei Ultracolour, I have light and dark patches all over my bathroom and I have no idea what to do, I called their tech team who thinks it may be that it was not mixed well or overwatered or overwashed, either way I have no way of proving if its a product fault or my tiler's competence. They also recommended Fuga Fresca which I haven't tried yet.