BigWallop wrote:

Marine Ply, yes. Ordinary Ply, no.

This has been covered many, many times - there's no need for marine
ply, and when most people say 'marine ply' they don't mean marine ply.

WBP (weather & boil proof) ply is perfectly suited to this task. It
costs around £20-£25/sheet (3/4"). Marine ply starts at around £80/sheet.


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Grunff