I'm looking at building a very simple 3x3m low level deck over a pretty flat paved patio. Whilst I have plenty of enthusiasm, my DIY skills are limited (as are my tools). I'm not looking at building something that will be there forever, but I obviously want it to be stable and safe.
What would be the major issues with building a deck base similar to that pictured below? With closely gapped joists sitting on pedestals? And no bearers/noggins? I'd ideally be using timber or composite joists, rather than the aluminium ones pictured. Is this setup only really appropriate with steel/aluminium joists?
Any help would be hugely appreciated. Thanks

