I think it means the slab need be roughly 150mm lower than the internal floor level, so when the decking been build , it will be as high as internal floor level ( not higher)
BTW, do you find any good landscaper / concreter (for driveway) yet ?
Yes we will be getting timber decking at the same height as internal floor level.
I have narrowed down to 3 choices, Icon Landscaping, G.Drosten Landscapes and Bellmark. Speaking with Peter from Icon Landscaping tonight to get a rough quote.
We're initially thinking about doing an exposed aggregate as the main base, but my wife is worried about cracking.
We are 2 months behind you
Interesting to see how the driveway / landscaping go