Thanks - I will take some wider area photos tomorrow.
Given that it won't be possible to put battens on to of the concrete (since there is a whole door system that opens over the decking with a clearance of a couple of cm) I'm guessing that decking tiles may be the best solution.
Or is...
Hi - noob here, so apologies in advance for anything dumb I say.
6 years ago we had a lovely extension of our kitchen built out into the garden, and using some dead space down the side of the house. It is a gorgeous design and even got short-listed for an award for our architect.
However...