I built a 3800 x 3440mm low-level deck on a concrete slab. The deck meets the house on two sides, with a 120mm clearance on one side and 110mm on the other, so I decided to keep the deck height just above 110mm.
I used 90 x 45 treated Pine joists sitting on galvanised brackets with about 10mm ground clearance. I was planning on using 70 x 45 joists, but MitchellMc suggested using 90 x 45 to stop the timber from flexing.
I ran the joists in the alternate direction to the decking boards with 400mm spacing on the joists to support the timber.
Oiled using Cutek with a matte finish.
Before and after
How to build a low-level deck
A low-level deck can pose a range of potential design and installation problems, with particular challenges around ventilation, drainage, termites and rotting. But it doesn't have to be a difficult project once you take the time to understand the basics of how they are put together.