In article , Danny Monaghan wrote:
The question is, to cope with the massive weight of water, should
I use 6" x 2" joists at 12" centres, or will smaller timbers
and/or larger centres be okay - or a combination of sizes? Also,
will a single layer of 16mm OSB me sufficient for the deck
surface, or would this be better thicker?

I agree with the others that this needs an engineer's design.
Domestic floor are designed for an imposed load of 1.5kN/m2
(30lb/ft2); you've got 1.05m of water = 10.3kN/m2 (218lb/ft2) - 7
times the load. Apart from the structural side I'd be concerned about
splashed water getting trapped between the underside of the pool
liner and deck surface.

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