Replies

1. 
   Mike_Mahan | Jan 19, 2014 11:48am | #1

   Stone mortar.

   Use a medium bed mortar designed for stone. It can be applied up to 1/2  or  3/4 inch thick. Thinset mortars shrink considerably.

   http://www.custombuildingproducts.com/products/setting-materials/medium-bed-mortars/marble-granite-travertine-premium-medium-bed-mortar.aspx

   http://www.laticrete.com/contractors/products/adhesives/medium_bed_mortar/productid/40.aspx

1. 
   royturning | Jan 23, 2014 03:41pm | #7

   Requesting product name and where I can purchase it

   Mike,

   Thanks for the reply. Can you provide the product name and where I might buy it in the Cincinnati area?

   Roy

1. 
   calvin | Jan 23, 2014 04:56pm | #8

   Roy

   here's the link again that he provided-a Custom Bldg product-available at Home Despot

   http://www.custombuildingproducts.com/products/setting-materials/medium-bed-mortars/marble-granite-travertine-premium-medium-bed-mortar.aspx

   and this one he provided-a Laticrete product-from a decent tile supply or maybe-Blowes.

   http://www.laticrete.com/contractors/products/adhesives/medium_bed_mortar/productid/40.aspx

1. 
   Mongo | Jan 24, 2014 01:07pm | #9

   check his links

   Mike gave you the info in his links.

   Custom's Medium Bed Mortar is sold at Home Depot.

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   Or you can use a couple of 1/4" thick applications of a non-modified thinset to build up your base to level. Non-modified is less expensive than modified, and gray thinset is less expensive than white:

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   Then when you set your tile, I recommend you use a modified mortar.. Flexbond is more modified than VersaBond, so Flex will give you a stronger bond than Versa:

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   Or you can use equivalent products from Laticrete, Mapei, etc.

1. 
   royturning | Jan 24, 2014 05:56pm | #11

   Progress with Med Bed Mortar

   Went to HD and got the Marble, Granite & Travertine Med Bed stuff. It was still pretty sticky to screed with a cleaned-up 2" x 4" but it looks like it will be flat enough for laying the travertine tiles with the thinset you recommend. I'm taking progress pictures of this project which will include all new mantel and case work. I'll post them to this thread for whoever is interested.

   Thanks again, Roy

2. 
   Mongo | Jan 24, 2014 08:12pm | #12

   good deal

   Glad to see you're making progress. The MGT is a modified mortar, so yeah, it'll have a little stickiness to it.

2. 
   sapwood | Jan 19, 2014 12:21pm | #2

   What you want to do would be OK but I think you'll find that thinset doesn't screed so well. Its too sticky. If you can stand the extra height I would suggest you set a layer of 1/4" hardi panel or similar first. That will give a smooth and level surface. 

3. 
   harri320 | Jan 19, 2014 10:48pm | #3

   I did exactlye this. Used a modified thinset, screeded it fairly easily with straigt board. Areas was about 2 ft x 5ft. Ended up about 1/2 thick at the max. Worked great and have had no issues after 6 months. good luck

   
1. 
   royturning | Jan 23, 2014 03:36pm | #6

   Please tell me brand name and where you purchased it

   harri320,

   There seems to be a great deal of confusion about thinset verses medium bed mortar at the hardware and tile stores. Can you tell me the product name and where you bought it?,

   Thanks, Roy

1. 
   Mongo | Jan 24, 2014 01:08pm | #10

   "Thin"set

   Roy, simply think of thinset as being used in "thin" applications to "set" tile or stone. It's really not intended to have an applied finish thickness of more than 1/4". Thinset doesn't have the bulk fillers that other setting products have, so if you were to use thinset in a "thick bed" application, as the thinset cured and consumed or gave up its moisture, it would shrink and crack as it cured.

   There have been quite a few cases of tile being set in a thick bed of thinset. The freshly set tile tile looked beautiful until the thinset started curing. As it shrunk, it started pulling the tile out of whack. Lippage and uneven grout lines are often the result.

   If you want to use thinset for your situation, then do it in mulitple layers to build up to your finished thickness. Example, if you need a finished half-inch thickness, then apply a base coat to fill in any mortar joints and to skim coat the tile. Shoot for about a 1/4" thickness. Let it cure, Than apply a second 1/4" thick coat over the first, building up to your half-inch thickness.

   As has been mentioned, if you want to go 1/2" thick in one coat, then use a medium-bed setting product. They have added bulk fillers so they can be used in a thcker application whtout the threat of shrinkage as the product cures.

   For those you'd be looking for bags that are labeled as a "medium bed mortar" or as a "marble setting mortar" or something similar.

   If you're familiar with sanded and unsanded grouts, where unsanded grout is used in narrow joints and sanded grout in thicker joints, it's the same idea. Sanded grout has sand in it to act as a bulk filler so it can be used in wider grout lines without the chance of shrinkage cracks as it cures.

   Unsanded grout is like thinset, if used in too thick an application it'll shrink and crack as it cures.

   Sanded grout is like medium-bed mortar, they have added bulk fillers so they can be used in thicker applications without the chance of shrinkage cracks.

4. 
   DanH | Jan 19, 2014 11:15pm | #4

   I've found that you can use thinset for just about anything.  Maybe not the ideal choice, but it feathers pretty well and is sufficiently sticky and shape-holding to be used for all sorts of repairs, and it's quite durable in most situations.

   The main problem with thinset is its dark color, which makes it a poor choice for, eg, patching chips in a concete porch.

5. 
   AndyEngel | Jan 23, 2014 01:08pm | #5

   Pay attention to the maximum depth. I've tried using it in a thicker application - maybe an inch? - and it does not set up. The instructions on the bag actually mean what they say. Who knew? In that case, I had to clean up and throw away the uncured thinset. I then mixed up sand and Portland to do my filling. That works fine.

6. 
   harri320 | Feb 24, 2014 08:31pm | #13

   Hi Roy. I used some left-over Ultraflex thin-set from Mapei. Probably could have used unmodified as well. Just used what I had. My biggest concern was the heat from the fireplace, but so far no issues after a cold winter of a lot of use. Good luck.