wrote:
The vinyl in our kitchen ends at the doorway where there is a step
down. To give a neat finish a gold coloured right-angled metal bar has
been placed over the wooden step.
However it is starting to lift in the middle.
What's the strongest glue/adhesive to re-stick such a bar to the wood?

Is this definately not meant to be screwed ?

If it has to be "glued"
I would probably use epoxy.

This is a site that deals with adhesives for pretty much all situations.
http://www.thistothat.com/
This site is American and as such tends to use american propreitry names
but two minutes thought/googling can usually dredge up the uk equivalent.