Materials list for exterior mosaics

Here’s a starter list of materials that you’ll need for creating exterior mosaics.

Materials (tesserae) for mosaic

Vitreous glass mosaics: Wide range of colours available. Flat surface. Suitable for outdoor projects. 

Glass: Stained glass comes in a range of colours. Can be used outdoors. Choose backing and adhesives with care, as may be visible through glass (using white powder adhesive will let the light shine through the glass). You can also get glass beads and gems, and other lovely embellishments like millefiori.

Shells / sea glass: Frost-hardy. You can set them into a bed of adhesive and cover them with masking tape if grouting to avoid staining.

Crockery: May be damaged by frost unless it’s not porous. To test its suitability for exterior use, put a spoon of water on the top of the surface – if it’s still there after a few hours, it’s not porous and is suitable for outdoors. If it’s absorbed, don’t use it outdoors. Fine bone china is ideal for exterior use and often has lovely patterns / flowers. 

Substrates / backing materials

  • Slate 
  • Cement foam board – I use 6mm cut up into the shape I require using a jigsaw. I protect the edges of the board using tile adhesive mixed with Mapei Latex Plus Admixture (50/50 water admixture). Then I attach fixings. Here are the fixings I use for 6mm cement board:
    • Button Fix Type 1 (a triangular shape with two holes)
    • M5 T Nuts (5mm AN90 on Amazon)
    • M5 countersunk bolts (16mm and also available on Amazon)
    • Check out my video guide to cutting and preparing cement foam boards for use with exterior (and interior) mosaics.

Glue / adhesive / grout

  • Powder adhesive (exterior) – use white if going behind transparent glass and you can buy a mortar tint (I use Mortar Tone from Toolstation) in black if you want to darken it.
  • Titebond II / III (Amazon). (Note: When I first attended a course to learn about exterior mosaics, I was taught to use exterior PVA and used it for many years successfully. However, having taken on board insights from other mosaicists since then, I no longer use PVA even if it’s exterior grade nor do I recommend it for exterior use. So, if you are using exterior grade PVA, I recommend you switch to Titebond II / III.)
  • Grout – exterior quality (the colour charcoal by Mapei goes well with slate or black is good either). (For grouting interior mosaics, I recommend a mid-grey colour as a good option if you’re unsure.)

Tools

  • Wheeled tile cutters
  • Tile nippers
  • Wheeled glass scorer
  • Runner (for snapping scored glass)
  • Glass cutting mat

Suppliers (I’m based in Central Scotland, so some of the suppliers are located there)

  • B&Q (grout, wheeled tile cutters, adhesive, tile nippers, plastic gloves)
  • Screwfix (adhesive, grout)
  • Toolstation (Mortar Tone, grout)
  • Amazon – Titebond II / III.
  • Direct Slating Supplies (slate) – Dennyloanhead near Falkirk
  • www.thecraftyglassbox.com (for mosaic supplies in the UK – tiles, glass, etc)
  • Pearsons Glass for stained glass in the UK – www.pearsons-glass.co.uk