Grouting nightmare - help pleaseee - Tile Advice

[Crumbs]

Hi guys, having a nightmare grouting a bathroom to a white colour.
I started with mapei ultracolor white, alot of it came out light grey and i ended up degrouting the lot as was not pleased with the colour against white tiles.

Now armed with grout 3000 in pure white, i done a very small section and again its come out light grey. Heres how i do it.

- Mixed with paddle and by hand, left to stand for 5 mins then re mixed to a paste.
- Applied with a float and removed excess with the float
- Waited 20 mins then sponged down. (2 buckets and wrung all water out of the sponge) lightly washed down.
- Used a plastic pipe to tool the joints after sponging down
- Left to dry

The remaining mix not applied has dried and is a pure white colour as expected so not the mix? Its been around 36 hours since its gone on.

According to the bag it will cure in 24 hours but it is on a waterproof membrane so is it possible it may take longer to dry out? what i did notice was when i done my first grout attempt with the mapei uc, the area above the sink did actually dry white and this is the only area that was not tanked so i am thinking that i did not give the grout long enough to dry?

Any help is appreciated guys as i am at a loss and tired of trying to get it to come out white, what am i doing wrong?? thx

 

[Andy Allen]

All grout will be darker till fully dry...
Are your tiles porcelain or ceramic?

 

[Crumbs]

Tiles are ceramic. I get that but the bag says 24 hours and after 36 hrs still looking light grey

Wondering if tanking behind the grout slows the cure? Does my method of application look good to you? Thanks bud

 

[Flintstone]

All sounds fine to me, the tiles aren't dusty and dirty are they ?

 

[Time's Ran Out]

I find with most grouts that they can take 3-4 days to fully dry and become water resistant.
It's often difficult to convince a customer that it will dry a lighter colour but it does.

 

[Gareth Raines]

After 2-3 days grout should of fully dried

 

[Italy]

I try,
If the ceramic has some glazed edges
and some unglazed,
The grouting, dries faster, where there is no enamel.
And more slowly where it is .
Usually when it dries fast, it remains beautiful white.
The color difference could be created by this factor.
which is very visible in the colored grouts.
It's just a matter of drying.
I hope you understand.

 

[On one]

This is one reason I dislike using Gloss white tiles ......
The tiles are white.
The trims are a different shade of white,
The grout is a different shade of white,
So everything is being compared to the brightest shade of white,which not the the grout.

 

[Time's Ran Out]

After 2-3 days grout should of fully dried

Not with Mapei or indeed Bal limestone.

 

[Crumbs]

Thanks guys...days passed and nothing changed, de grouted the small area. Regrouted a new test areas... and come out grey again. Did 4 areas, 2 on tanking membrane with a sponge washdown and one without (just tiles cleaned and joints tooled) and 2 on area above sink with no tanking with and without washdown.

All 4 come out light grey / ivory ish. I know its going to show up more against white but its no where near "pure white". Sanding a little of the top reveals white lines, really confused to whats doing it now. Considering remaining paste is bright white and no wash down to remove the possibility of excess water. Only thing maybe causing it is using a plastic pipe that breaks up the grout lines weaking/damanging the grout.

Think i will try to source bal micromax 2 snow grout, meant to be a brillant white. Anyone know where i can buy it from - no where seems to stock it.

 

[WetSaw]

Had your grout float has only been used for white grout?

 

[Time's Ran Out]

Had your grout float has only been used for white grout?

Now that is an interesting question.

 

[WetSaw]

The sponge ones with the rubber face can become stained with coloured grout. I only use solid ones now and still keep a separate one for white.

 

[Crumbs]

Never used on anything but white grout bud, going to try some different finshes (sponge, finger, plastic pipe) only thing left i can think is causing it. Other than that will swap out for MM2 snow

 

[Tile Shop]

The snow is a difficult colour to get at the moment. Its fairly new and will take a little while to filter through to all the suppliers.

Before ripping it out and starting the test again, you could try epoxy or a grout colourant such as Mapei Fuga Fresca or Universeal Grout rescue. At least that way you'll have a back up option to try if you never get the brilliant white you are after.

Do you have any pictures of the existing grout so we can see how bad it is?