Base for track

[barney121e]

I have a baseboard made of wood and ply. I need to have the track higher than the baseboard. Have some polystyrene to raise height but do I need to put anything on top of this like more ply or card, or can I just put trackbed down?

Any ideas, much appreciated.

[Bufferstop]

You could lay it straight onto the polystyrene if you are gluing it down, but it doesn't provide a good anchor for things like signal and telegraph posts, a strip of thin ply (no more than 4mm.) slightly wider than the track should be all you need. Glue it down with something like "No more Nails"

[barney121e]

Would balsa wood be any good?

[Bufferstop]

I almost suggested it. I'd seal it with some varnish before track laying, you don't want it to curl when you start ballasting.