Me too. The flat-roof dormer hangs off a joist that runs the length of the ridge. My builder let me and my mate hammer the girder into place, then everything hangs off it. Looks like this herbert thought he'd take the roof off and do the joist later.
wow thats 2 mins away from where i live and i had a loft extension. seems like i managed to get off lightly. good to hear no injuries etc.