Marble Tile install

[jphavener]

Is the installation of Marble tiles any different than ceramic? I know that marble isn't suggested in a kitchen but how about a bath floor? I have never installed a marble before and I want to make sure that I don't goof it up.

[Steven Hauser]

Yes there is a difference... a big difference.

The subfloor stiffness needs to be better, load capacity more, the natural material has ideosyncracies that you have to be aware of and cater to. The grout joints are typically 1/16" and lippage no more than 1/32".

Mud and subfloor knowledge, a level, different thinset and lots of experience.

In a bath; care and maintenance are important, (and for crying out loud, just because I just had to repair this for someone else) don't use muratic acid or lemon juice or vinegar or any other ancient marble secrets to clean up grout haze.

IMO put it on your floor first or help an experienced marble setter.

Steven

[John Bridge]

Start out on ceramic and work your way up to stone. There are experienced tile setters who can't handle stone tiles. Take baby steps for a while.

[jphavener]

Cool, thanks for the replies. I was concerned about that. I have done work for this guy before, and I am not positive that he is going to use marble, but I will let him know that he needs someone experienced in stone work to lay it if he wants to use it.

Just so I have a better understanding, why is it so much more difficult?

[Cisco]

Without getting into any kind of detail there is a lot less room for error with stone. Special installation materials, stiffer substrat requirements. Like John says some experienced setters cant install stone. The basics of installating ceramics apply along with a lot of other techniques that come with experience.

If you have some tile installations under your belt installing a stone floor wouldnt be that difficult.


©

[jphavener]

I have 20-25 tile installations under my belt but, I would hate to screw up anything. I am not worried about subfloor stiffness because it is a cement slab house. While I am not afraid of doing it, I would hate to mess up his floor and my name. I think I will defer this one to someone else. Maybe later in the future I will feel more comfortable doing stone for someone, but not right now.

[JC]

Want more?

Well to begin with no two stones are the same...many differant types of marble...some are not even rated for floor use...some will warp when exposed to moisture(from thinset). Some will reguire using an impregnation sealer to protect them...and yearly maintenace also with sealer.
Depending on the stone and the porousity levels some marbles would be better then others.
By letting the guy pick out the marble using color as his only factor is a big chance....When the rock comes from HD and is in cardboard boxes and practilly falls apart just by looking at it could be becuase the HD purchasing agent brought the cheap fissure ridden liftover slabs at the quarry.

On a concrete slab it would also be wise to consider a moisture membrane like Nobleseal ...since alkylinity and moisture can cuase serious discoloration problems also. That an owning a cup grinder will help tremendously to prevent lippage.

Choosing thinset is another issue..grey thinset can discolor light marble and it is also wise to use medium set with bigger notches or back buttering each peice.

Some have polyester/mesh coating on the back to hold them together that cuase bonding issues.

I would tell you more but I am just learning myself.

[jphavener]

JC, are you just picking this up by helping an experienced stone guy or are you getting your information from a source that I can get my hands on? That is some really good information, and I will have to remember that.

I have heard you and some others mention lippage. What is that?

[Cisco]

Give use some more information on the material you looking to use and the substrat your installing over. The guys here will have enough information to guide you through the install.

Dont give up, any questions you have can be answered here...

[kemguru]

I absolutely agree with Cisco

Let us know more about the marble, you then can explain to the homeowner/GC the pitfalls of that particular stone, then have them sign off on it. You know, a C.Y.A. sheet. They are picking the material, you are just installing it. You can educate them on the stone, then if they still choose to use it, you are only responsible for the installation, which by the way, coupled with your hands on experience and the support from this board, you should do just fine. The installation will take a bit longer, but it will be well worth it

[JC]

Some I learn from my stone buddy but mostly I do alot of reading...learned along time ago that depending just on learning from one guy can get you steered the wrong way more often then not...more sources the better. It's all on the net buddy..use the search engines.

[jphavener]

okay, here is what I know so far. The subfloor is cement slab. I imagine that the marble tiles are from a home improvement warehouse, but I could be wrong. It is a bath so the marble will/could be exposed to water.

[kemguru]

Alrighty then, some might think this is overkill, but you will be covered. Remember that C.Y.A. sheet now.

Vapor test, you want less than 3 lbs/1000ft2 over 24 hours.

http://www.moisturetestkit.com/

Cheap, fun (for me ) and you will learn something new. Plus, cover your ass.

Another way to test is to do a pH test. The best way is to grind off a bit of crete, put the dust in a small container, add a very little bit of bottled water, dip some pH strips in it. You want the pH to be less than 9. A higher pH means excess moisture. The moisture pushes salts to the surface, and this can cause a world of problems.

I dont have anything good to say about marble in a bathroom, unless its a green marble. Most big boxes sell junk for marble. Just do your tests, advise them of the pitfalls of their material of choice, then have them sign off.