Grouting oyster slate

[robin-m]

Hi, I'm not a pro tiler but am hoping to get a bit of advice from those who are. I'm laying about 40 sqm of oyster slate floor tiles starting with a shower room and extending into the kitchen / diner. The tradition float method of grouting would be impossible to clean up given the rough surface so I'm going to use either a grout bag or mortar / grout gun. Before doing so I have a few questions.

1. Are the guns better than a bag (I've not used either before)? I've read some good and some terrible reviews on the guns.
2. After piping the joints how long do you leave the grout before smoothing the joint? I've seen a you tube vid where the guy wipes the joint with a sponge straight after piping in the grout which seems to smear the grout over the face of the tile.
3. Whats the best way of smoothing the joint

Sort of related, the shower room is a wet area. I've installed a wet deck and tanked the whole room (screed floor). Should I use Silicon in the envelope cuts and to seal in the drain or just grout the joints like the rest?


Thanks
Robin

 

[White Room]

A bag IMO would easier, fill the joints and wait for it to dry slightly and then use a pointing tool to finish off...has the retailer mentioned anything about sealing the tiles.

 

[robin-m]

Thanks, yes, I will seal the tiles prior to grouting and then again afterwards.

Robin

 

[Time's Ran Out]

I've personally never had the need for a bag and only use the gun on brick slips.
Oyster slate is always spotless and dry before being well sealed and the grout is confined to the joints only then washed off within 15/20 mins. Sand/cement mix is good for this type of slate or sandstone grout.

 

[robin-m]

I've finished the tiling but still need to clean, seal then grout. When the tiles were ordered the supplier also included sealant which is LTP colour enhancing. I've tried it on a few offcuts and really don't like the fact that it darkens the stone as if it were wet. I believe that Lithofin stain stop impregnating sealer can be applied without changing the colour. Is this the case before I rush out and buy a test can or, can someone recommend an alternative?

I'v attached a picture showing the colour that I want to preserve.

Thanks.



If my wife ever picks ungraded tiles again I'm getting a divorce!

 

[Ian]

LTP mattstone doesn't alter the finish of the tile. If you do buy some, make sure it's the one with the purple label not the hippy Eco one with the green label. It's twice the price as well.

 

[On one]

Yeah,Lithofin Stainstop will not change the colour of the slate. Just make sure you ventilate the room if you get the solvent version.
Whilst I can see why you have done it,I would have gone for a different pattern.

 

[robin-m]

Thanks for the replies, I'll get hold of a can of Lithofin and give it a try. I might get some of the LTP as well for comparison.

As far as the pattern goes it is a lot easier to see in the photo than in real life. The intention was to give a random effect which it actually does unless you stare at it for a while.

 

[Andy Allen]

I like it........looks a good job, you should be proud of yourselve...

 

[robin-m]

Done! I tried both the LTP and Lithofin on test pieces. There was some colour change with the LTP but none with Lithofin so went with that. Using a grout bag was easier than I thought it would be and I'm really pleased with the results. Thank you all for your advice, it really helped.



Kitchen finally going in...