Asked on Apr 30, 2017

What glue and grout do I use on mosaic for outside table upcycle.....

Jill Glover
by Jill Glover
I have a small round table and want to make it into an outside coffee table
  5 answers
  • Tim Tim on Apr 30, 2017


    What Is Thinset Mortar?

    For outdoor and wet mosaics, thinset is recommended instead of adhesives. Thinset is a bonding mortar, which means it is a portland cement (the same as used in concrete) with polymers added to make it sticky and extra strong. This is particularly important when working with glass mosaic tile, which is non-porous and difficult to bond securely.

    We use Versabond brand thinset which comes in a 50-pound bag. Buy a 5-gallon plastic bucket with lid at the same store you buy the thinset and put the bag directly into the bucket without emptying it (which would create an enormous amount of dust). The bucket helps contain dust and keeps humidity from ruining the mortar over time. Slit the top of the bag and use a long-handle spoon or garden shovel or ice scoop to take out what you need. The mixing ratio is 1/4 cup water per pound. Wear a dust mask and scoop and mix the thinset outdoors.

    The Ceramic Tile Institute of America has written some illustrated instructions for installing sheets of glass tile outdoors. These instructions include pictures of using a notched trowel to spread thinset mortar for mounting a sheet of tile at a time. I have written some instructions for how to use thinset for detailed mosaic artwork where the artist wants to mount one tile at a time.

    Outdoor Grouting

    We use traditional portland-cement grout for our projects, but some of the newer epoxy-based grouts may provide additional water resistance. For outdoor projects, we will often use thinset mortar for grouting as well. We do this for two reasons: the thinset will match any thinset that squeezed up between the tiles, and thinset is harder than grout.


  • Glenda Glenda on Apr 30, 2017

    Wow. Since I am a mosaic artist, I thought this was the one question I could answer. But, Tim has it covered! I would only add that any wood you mosaic on will draw moisture and your mosaic will eventually fail. If your making a table, use hardy board or cement board to cover the top before you mosaic!


  • Deborah Anthony Deborah Anthony on Apr 30, 2017

    I found Alene's permanent water proof spray glue to be good for placing your mosaic pieces, then an outdoor grout, not sure to tell you specific brands, check labels or get help at the store.

  • Jill Glover Jill Glover on May 02, 2017

    Thanks. I didn't realise there was inside and outside types of grout. Thanks for the info.

  • Jill Glover Jill Glover on May 02, 2017

    thank you for that. There is a lot of information there. I will source this product and use it.