Browse Forums Landscape & Garden Design I'm about to put down some Merbau. Is it necessary to oil underneath the boards before laying? 0 2805 Hey There. No problems re jumping in. My original question was "should I have waterproofed" the concrete slab before putting batons down. We have been told we should… 7 5058 As above, you will need to trim your sheet to land on the joist, also make sure you are running your length at right angles to the joists 2 2196 ![]() |