Thanks, I have only just spotted your reply, it is wood essentially bolted to the concrete which was laid on top of the existing patio. And bolted onto the single skin brick outhouse and garage. The roof then rests on top of the frame and is screwed to the outhouse and garage.
I have a few...
Between our garage and the outhouse a previous owner of our house built a lean to 'extension' using wood and corigated pvc sheets. It is horrific. We can't afford to get someone in but it does need sorting asap as the whole thing is rotting.
One tiber wall/door plus the roof forms the the lean...