Whilst I've got the shape worked out, I was debating if I should tie it to the house using a ledger board or make it somehow stand by itself. Initialy, I thought tieing it to the house may be easier as it was only going to be at max 10cm in height. By doing more and more measurements, I realised that the height of 10cms is too low as further down the deck, the top of it would be at the same level and even below the ground level. So queue the re-design. I've decided to raise part of the deck to 25cm which will solve my problems with height. Great. At the same time, I've decided not to tie it to the house and make it free standing by attaching post brakets to the concrete which obviously raised the cost of the project by about £100 - £150. Here is the progress of fitting post brackets using 10mm x 50mm anchor bolts. That should do the job. 1 done - 7 to go.
After more time, I am almost done and the cat seems to approve it. The brackets do feel sturdy. I've tried moving them by hand and even pushing them with my foot and they were not moving at all. I am a pretty big guy (17st) so I think I produced enough force to test them.
This is not as long as expected, but the wind is picking up and its getting late so I'll just leave it for now.