Flooring and Carpeting/Carrara Tile


Hi.  We have 2" Carrara Marble mosaic that we are installing over Schluter Ditra.  Ditra calls for an unmodified thin set mortar to be used but I know that special care has to be taken to prevent staining on the underside of the marble tile.  Should I just be looking for an unmodified thin set in white or is there a specific brand or type that I need to use?  Please let me know at you earliest convenience.  Thank you!

Thank you for your question JStar...

  Whenever I am installing a light colored Natural Stone I will be sure to always use a "White" thinset whether it be a Latex modified or a standard thinset. I have used both installing over Ditra depending upon how much time I have for the install. My personal preference is Mapei products and they do have both types of "White" thinset and both will perform to expectations. When attempting to install a Mosaic (no matter what the material is) it is best to flat skim or fill the Ditra first and let dry over night so that you will have a nice flat (and firm) surface to work from. This will reduce the possibility of having any corners settle or drop down into one of the open cells because the thinset is still soft or that an individual tile on the mesh be mounted oddly and out of level with the rest. That typically happens after you have cleaned up and quit for the day only to discover it the next day...follow me? Also in order to help keep the Mosaic's all running flat keep a grout float handy so that you can use it as a "beat block" (gently now) as this is better than trying to use your hand which isn't as big or as flat, ok? Just spread out the thinset..lay out the Mosaic where you want it...and use the float to gently tap the squares uniformly into the thinset. Once you have them all flat you can adjust the joints so that they are also uniform without disturbing how flat they now are. Ok JStar...I hope this helps you with your project, feel free to return anytime..

Perry V.  

Flooring and Carpeting

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Perry Vellenga


Ceramic Tile/Marble. I can answer questions about floor preparation, tile selection, layout questions, performance of products, expectations of finish, compatabilities, questions about grout and epoxies, evaluating an installer, asking the right questions to check competence...more? 33 years this August 2012/ many years in commercial application from exterior finishes to Mall store fronts/ interior finishes like floor packages in stores inside Malls examples: The Limited, Lerner/NY, Lane Bryants, Bombay Co., Now involved in Residential new construction covering all types of interior finishes and designs.


I worked in an exclusive field of floorcovering called "Tenant Development" which is by invitational bid only, by way of a National bid list. These are large floor packages usually over 3500 sq. ft. of 18" x 18" Marble and Granite and many other types of Marble and sizes. They are specialty stores where the floor package can cost upwards of $50,000 for one store. I have also done "Structure" stores and J. Riggins stores, Lane Bryant,Express and Body Shop stores where wood flooring is used. Presently work for a National Flooring Company in the Residential new construction arena that covers most interior design elements..Granite Slab tops/wood flooring both job finished and prefinished ect..

My response's are published all across the Internet and picked up by multiple Interior Design sites and Industry related web sites where people have questions...

too many most of which don't count...

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