"Walter R." wrote in message
...

I would like to glue some 4x4 ceramic tiles (house numbers) to my entry
door. (Covering up some discolored areas.)

The door was previously coated with satin spar varnish. Will any glue hold
on the varnish, if so, what kind of glue should I use?

We cannot answer without more information.
Adhesive properties vary with humidity, high and
low temperatures (cf. differential rates of expansion
of ceramic and wood materials), exposure to rain
(whether ice or rain can build up on the top edge
of the tile and pentrate behind it (and so on.)

The simplest way to attach tile to wood is usually
to place the tile in a wooden frame that is screwed
to the wood.

--
Don Phillipson
Carlsbad Springs
(Ottawa, Canada)