Ok.
2*1 timbers - 6mm ply and cork over the top to stop the noise. A fold up against the wall 8 * 4 plus extension into another room "trainset" (a couple of steps up from trakmat - 2 loops controlled from different ends of the layout to stop arguments; all points at the front to enable them to reach derailments; the inner loop raised to allow scenery and decorations (he's made 2 Wills kits :-)) to be left down (and not knocked off by enthusiastic
5yr old fingers)
But do you
1 "cork" the whole board
2 put chunks of cork roughly where the track is going to go, paint it and trim it up after precisely laying the track or
3 Cut out strips of painted cork and try and lay track/cork strips at the same time?
I wasn't planning on ballasting for a while at least.
Ken