Hi
If you want to use a thinner membrane then use Durabase WP it will do the same job as WOP but I would recommend you use Durabase CI as this will waterproof and uncouple your floor so preventing cracking from the latteral movement of the boards.
You seem to of jumped around from system to system, Marmox insulation board former, Aquapanel substrate boards, Durabase W0P Homelux, is there a reason for this ?.............confused
tiler
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