Very easy, so long as the marble's well adhered, and there's no cracks in it.
Start by scrubbing the marble down with a detergient called TSP (trisodiumphosphate). It can be found at any big box store, and most hardware stores, as well. It's some of the best degreaser around, and will get rid of alot of the soot and garbage that's built up on the stone over the years. Once that's done, hit the face of the marble with about a 50 grit sandpaper on an orbital sander to rough it up a bit and give the thinset a better bite. Once this is done, use a high latex content thinset-- something like Laticrete's 254 or Hydroment's Reflex. Either of those would be "mix with water" thinsets that you could use. Another possibility would be to use an UNmodified thinset, such as Mapei's Kerabond, and mix it with their liquid latex additive Keralastic, or Laticrete's 317 thinset mixed with their 333 additive. The object is to use as strong a thinset as you can to get a really good bond. From there, it's a matter of putting up the tile. You want to make sure you use spacers, otherwise the tiles will slide. What I woudl suggest is to lay the spacers on their side, rather than using them as they're normally used. Also, pick up a jar of marble wedges (they're little 1/2" plastic wedges that go from a point to 1/16" thick at the back end). They're great for using on top of the spacers to take into account the minute difference in sizes of the tiles.
I hope this helps!
Just a quick P.S.-- DO NOT let anyone talk you into using mastic or premixed thinset!! ANything that you just open the pail and spread will be no good in this instance. The heat will make it brittle, and your tile will end up falling off the wall sooner or later.
"Whether you think you can, or you think you can't, you're probably right."
There is a marble surround on our fireplace. It appears that the marble was adhered directly to the underyling brick. (The rest of the brick is covered with drywall). We don't like the look of the marble, and rather than pulling out the doors and removing the marble, is it possible to just tile over the marble with a granite or ceramic tile? OR, would this be too heavy and possibly cause the marble to come loose?
Yes you can but you must prep the Marble first to accept the adhesive. I would use adheasive instead of thinset simply for bonding reasons I believe the adheasive would make a better bond with the marble surface. Ofcourse if the fireplace is used I would be sure to check the manufactures comments on heat. If you go with a cement product (thinset) I would strongly suggest after etching the marble surface applying a bonding agent to the marble priror to putting it on. This product can be obtained at any Lowes or Home Depot and is generally Refered to as "concrete bonding adheasive" it looks and smells exactly like elmers glue. Keep in mind if you do not etch (scratch) that Surface espically with the heat of the fireplace you will have bonding issues. You can find more information on ciciliotandson site
