URGENT - need advice on natural slate tile selection

[jdf405]

Hello,

I hope I can get some advice rapidly. I have two major concerns:

1) We selected natural slate tiles (12x12) for our 25 sq ft. bathroom floor. The installer is coming next week. When I looked at the tiles today I noticed that small chips (1/8" to 1/4" approx) of slate come off fairly easily with a finger nail flick etc... I am worried that the slate will continue to flake and cause chips to get on people's feet and scratch the tub & wood floors around the house. A guy at the tile store said he thinks the penetrating sealant will stop it, but I am skeptical.

2) The slate naturally has significant thickness variation within a given tile. I am concerned about the sensibility of having edges of 1/16 to as large as 1/8" to stub toes on. I am worried this is a bad idea for a bathroom where people are frequently barefoot.

I'd like to be able to give the installer as much notice as possible if we need to reconsider.

Your input & guidance is HUGELY appreciate!
Have a great day.

[jdf405]

We do have a call into the tile store. The first guy we spoke to said he "thinks the sealer will take care of it." I am fairly skeptical of how a chemical that is applied in a thin film at long intervals is going to keep stone together when mother nature didn't intend it to be so...

The house I grew up in in NYC has slate roof tiles that have been exposed to summer & winter extremes for nearly 80 years and most of them are still in excellent condition. I don't doubt that slate can be an amazingly durable material, I am just quite suspect of the specific slate we have selected.

What do you make of the edges protruding?

[jadnashua]

A typical penetrating sealer won't glue the tile together. Not all slate is created equal. Much of the stuff is really shale which is not much more than compressed mud, especially some of the stuff sourced in China. A (true) hard slate is metamorphic rock - heated and fused together by nature. Any slate can flake as it is a natural substance. A hard slate can be ground and rectified so it is as flat and square as a typical ceramic tile. It has the color but not the texture (think a slate chalkboard if you are old enough when they weren't some manmade substance). I think a rustic slate in the bathroom floor might not be a great choice. There are slates that would work well. A second major consideration is that regardless of the size of the room, a natural stone installation requires twice the deflection rating verses a ceramic one. And, requires two layers of plywood or a sufficiently thick mudbed (cbu is NOT a substitue for a second layer of ply or a mudbed).

A simple test you may want to do is stick one of the tile in a pan or bucket of water overnight. Then, rub a white cloth across it. A true slate won't sluff off anything. Some of the stuff sold as slate will start to disolve and make the water muddy, and the cloth darkly colored from what's disolving. You want to avoid this type at all costs.

Check out www.johnbridge.com for help on tiling issue.

[Mike50]

I use Jasco Gloss & Seal on my Saltillo tile. It's very effective at keeping all the tiles intact and free of flaking etc. This natural tile is in both of my bathrooms BTW.