I haven’t used this particular grout. But researching it, if properly mixed and applied, it would work for the floor shown here. It’s made to fill joints from 1/16”- 3/4”, but it is a fast setting grout. I’m thinking they either added too much water at the beginning, or more likely added water when the grout started to thicken up. When they went to redo it, if they didn’t remove all the old grout, the new grout is not going to work. I don’t believe the grout was defective, I’m going more with improper application.
Mike Hawkins

 

My buddy said he was there when the owner came to do it. Then when he did his own test, he said he meticulously followed the instructions. Would not removing ALL of an improperly mixed grout already in the joints make the new stuff not work?

 

Using that grout it is important that you follow directions close and measure your water and grout. Use cold water also. .
I use that grout on everything and no issues that your having.

 

Premixed the dry grout, mixed 3:1 by volume (3 grouts and 1 water) for 5 min by hand. Let sit for 15 min before sponging. Waited 20 hrs then dug it up like this.

 

Is that the mix that the bag gave you?
I would not mix grout by hand. Use a mixer on a drill.
Fa grout you use as soon as it is mixed. No waiting.
Fa stands for fast acting.

 

I doubt the grout is defective. Probably too much water in the mix. Are they using sanded or unsanded? Joints look a little narrow for sanded.

 

The crew did it twice and owner of the company did it once and buddy did once. The first two crew attempts were with drill mixing. owner and buddy did hand mixing. It's just hard to think that an experienced contractor would get it wrong 3 times and a home owner would also get it wrong. They're going again with a different product.

 

Now, ask me why I use Prism grout by Custom. I've had the opposite problem with Mapei grout in that the overwipe glaze would not come off after 20 minutes. I used muratic acid to no effect. Swore off their products at that time.

 

not sure if this is a mixing problem anymore, as 3 different persons try it, maybe it comes with defect

 

They redid it with Bostik Hydroment Vivid and it appears to have gone well this time.

 

Nope. Just got a report that the new grout is soft. Mixing this stuff isn’t rocket science. Is hard to believe that 4 attempts would fail. Is it possible that there’s something wrong with the water? It’s just regular city water.

 

It’s just regular city water.

If it were Sarasota, I would say yes, but you're in the panhandle, right?

 

I doubt those planks are soaking up water from the grout. You do have it set on a backer, right? When I was much younger, I laid tile directly on plywood. Grout just turned back to powder the next day, for several applications. A friend told me what the problem was. Even the tiles weren't too difficult to pop up and do it right.

 

It's a slab on grade. Everything placed directly on concrete.

 

Could the concrete or tile be too dry and sucking water out of the grout? A contaminating film on concrete or tile? The put a glob of grout on the counter and he said that hardened nicely. Here are pics with the new Bostik grout. I know aluminum is bad for concrete, but they're using plastic tools so that's not an issue.

 

I'm thinking maybe the concrete (or thinset or whatever) underneath is sucking water out of the grout (or vise versa). The same tile and Mapei grout was used upstairs over plywood/OSB and performed wonderfully. Would epoxy grout be a good bet to use in this problem area?

 

Wet the joints before grouting. I never had that issue . . Cannot think of a reason the grout would do that besides mixing but I think you got that covered.

 

You'd think grout would last a really long time in the powder form, but I have tried using old stuff a few times and it didn't really work after a couple of years. It gives similar results to what you are getting. So, yes, there is such a thing as bad grout. Maybe he wound up with a stale or defective batch.

Seems pretty unlikely that they will throw you extra cash, though.

 

Hello Chonks!

Ultracolor Plus FA & all of the heavily polymerized materials are really sensitive to slake time. If you check the instructions you'll either see a stated slake time or it will give a minimum mixing time.

The second is more likely because that grout has extra polymers to speed curing, plus it has stain repellent additives. It slakes while you're mixing. Also, don't mix aggressively. Excess air isn't good.

As a side note, I've never been a grout "washer" for joints 4mm wide and above. I learned this as a kid when I worked for an old-country tile setter.

I'll sprinkle dry grout on and use a hard rubber dry float to push it around. It'll pick up the excess grout and beautifully polish it without adding excess water. Next, I sweep it up with a soft brush.

For a final haze cleaning, I'll spread barely damp sawdust around with my hands, then sweep it up. You'll see the sawdust change color as it picks up the haze. Your joints will be smooth as glass.

I hope your project goes better soon!
Paul

 

I was recommended a tile guy, so I passed the info along for a second opinion. They're supposed to meet tomorrow. I wonder if storage could be an issue. If it was stored outside or in a garage, that may have compromised it? The second round with the new grout came straight from the big box to the active project tho.