How to mount ceramic tiles in a wrought iron frame?

Question

I bought my wife some ceramic house numbers and a wrought iron frame for Christmas. I had assumed I could just pop the numbers into the frame, but that is not the case. The numbers are free floating, and do not fit into the frame snugly. There is about a quarter inch gap all the way around. Please see picture.

I thought about cutting a piece of wood to fit the wrought iron frame and adhering the tile to the wood, but as this will be outside I was concerned about wood rot and whether the tiles would adhere well.

I have never worked with tile. I also live in New England where this style of house numbering is never used. So I don't have a neighbor's I can inspect for ideas. I guess my specific questions would be:

1. Is it a good idea to adhere the tile to some sort of backing?
2. Should the backing be wood or something else?
3. What kind of adhesive can I use to stick the tile to the backing?

Answer 1

Probably the nicest way to set the tiles into the frame would be to use a tile setting cement and grout compound. A bead of the tile setting cement can be fitted around the frame channel. Then the tiles can be laid in and pressed down till each is even and spaced nicely. After the setting cement has dried you could come from the front and apply grout in between the tiles and around all the edges. Done correctly this should secure the tiles in a way that will stand up to the outdoor weather.

It is possible that you could use a construction adhesive such as Liquid Nails to glue the tiles to the lip of the frame instead of the tile setting cement.

Answer 2

I would cut a piece of plywood as close to the inside dimensions of the frame as you can. Paint the plywood with an exterior primer and a coat of paint. From the aestetic point I would use black paint. Install the tiles and glue the plywood in place with construction adhesive. The idea is to allow the tiles to float as the frame and wood expands and contracts with weather changes. You could also drill some small holes in the frame and insert some small wood screws into the wood to hold it in place.

Answer 3

If you decide to glue it, I would consider using a silicone adhesive, as it will flex as the weather changes. An adhesive that is too rigid could cause issues.