All that is left to do on the roof now is to put a Green Stuff apex on the top and do a little filling along the ridges.
Having completed the roof, I cut a sheet of textured plasticard for the platform surface. The texture is a little more regular than I would have liked, but an irregular pattern was not available. After cutting the basic shape, I cut out the area beneath the building, not only to save some of the sheet, but also to provide a better surface to eventually glue the model to.
The final task was to fix the lintels above the windows. These I cut from 1mm cork sheeting. I used this because when painted it has an interesting rough finished stone like texture.
The next step is to construct a covered portico across the front of the main structure.