Patchy Mapei grout... any ideas?

[bugs183]

I know it doesn't make sense at all, i'm just throwing ideas out there. Nothing worse than having to go back to a job and re do it due to product failure.

 

[richardbell81]

I know, is it worth contacting mapei?

I ordered the grout online as I couldn't find it in that colour in any local shops... When it arrived, the bag did have a hole in although it was delivered in a box. I obviously didn't use any of the powder that had come out of the bag... But I'm wondering if that had anything to do with it. Can't see why as others seem to have had the same problem. I'm just struggling for answers!

 

[Muse2k8]

It may just be excess moisture in the grout. What temp is the room at and is the room prone to humidity? What appliances and utilities do you have in this room or have used in the week or two prior to grouting? Are there windows or a door? Any pets? Anything (even a kettle).

Slightly off topic but a mate recommended PCI grouts. Anybody tried these?

 

[Muse2k8]

I said kettle I meant shower lol. Don't ask... I was making a hot choc lol.

 

[jay]

Can you give us a detailed description on how you mixed the grout thanks

 

[John Benton]

BAL Micromax, super flex and microflex, basically BAL. I have always used BAL and on the few occasions I've used ultra colour I've had issues, either setting too quickly, drying patchy etc, I also don't like the fact that it needs to be mixed a whole 5kg bag to exactly 1 litre of water, to me that suggests that it's too sensitive. I've read too many posts on here with it going wrong from DIY and pro's. I know a lot of folks on here love it so it must be a decent product, but not for me.

I had the same problem with the Ultra chocolate grout, very patchy. Raked out first thing next morning and re-grouted with a brand I regularly use, Atlas.

 

[IvegotsTILE]

I've just had this problem in 3 bathrooms with bal superflex,really annoyed me. Have had it on a few jobs over the years and cant explain how 1 grout line can have 3 different shades when it has been mixed properly and washed down the same.

 

[richardbell81]

It may just be excess moisture in the grout. What temp is the room at and is the room prone to humidity? What appliances and utilities do you have in this room or have used in the week or two prior to grouting? Are there windows or a door? Any pets? Anything (even a kettle).

Slightly off topic but a mate recommended PCI grouts. Anybody tried these?

The house is a 1902 mid terrace but it is not being lived in at the moment so no pets and the shower hasn't been used. I can't say that the room is prone to humidity as the door on the bathroom has been removed temporarily so it gets a constant flow of air. Obviously there has been no central heating turned on either so i'm still clinging on to the hope it will take a bit longer to dry out

 

[prceramics]

I have had similar problems in the past with this grout (Jasmine) and have read a few similar posts reporting the same problem. I had to recolour the grout to solve the issue. I will never use this grout again as I really don't rate it, it's far too sensitive and not user friendly (this is my own opinion).

i have a job next month and the customer has asked for this grout (jasmine) might try and talk her out of it

 

[richardbell81]

Can you give us a detailed description on how you mixed the grout thanks

1kg of grout with 0.2 litres of water (as per instructions but my floor is only 2.2 square metres so no point mixing a whole bag of 5kg).

Poured the grout into a bucket containing the water, mixed to a peanut butter consistency with a hand trowel (it did seem thicker than BAL grout though).... left it to rest for a few mins... mixed again... then applied with a float.

As an additional note our water in this area is soft water so I can't blame hard water with high mineral content.

 

[jay]

Might be worth trying a electric mixing paddle

 

[charlie1]

I have had similar problems in the past with this grout (Jasmine) and have read a few similar posts reporting the same problem. I had to recolour the grout to solve the issue. I will never use this grout again as I really don't rate it, it's far too sensitive and not user friendly (this is my own opinion).

agree bri, ultracolour is messy to work with, falls off the float very easy, generally a messyer grout compaired to the likes of bal. I like bal and sovregn now.

 

[Andrew Oates]

Was told by mapei rep mix with drill leave 5 mins for colour pigment to break down then mix again

 

[Andrew]

Are you certain 100% bond was achieved on the tile? I used nothing but mapei for years and had this problem on a couple of occasions! If voids are present in the adhesive grout can flow into these areas making that area of grout hold more moisture than the rest, therefore drying unevenly. How long has it been grouted now?
You seem to have followed procedure correctly, so this is all I can think!

 

[richardbell81]

Are you certain 100% bond was achieved on the tile? I used nothing but mapei for years and had this problem on a couple of occasions! If voids are present in the adhesive grout can flow into these areas making that area of grout hold more moisture than the rest, therefore drying unevenly. How long has it been grouted now?
You seem to have followed procedure correctly, so this is all I can think!

I grouted on tuesday evening and it was still patchy today. I used a standard 20x10x10 u-notch and back buttered all the tiles to ensure 100% coverage! I made sure all the voids were clear i.e no adhesive seeping up the sides... i don't really know what else I could have done! So frustrating! Even if i rake it all out and start again, i'm not sure what I could have done differently!

I suppose use a paddle and bottled water... but it's getting a bit ridiculous when you have to go to these extremes to mix up 1kg of grout!