Octagonal Roof?

[RockandGrohl]

Any way to make a pitched octagonal roof, without the large castle building pieces? I'm ideally looking to make it from the sloped 1m Wooden veranda roof and corner pieces but can't work it out.

Each side of the octagon is the width of a shop fascia, I can't figure out how to make an octagonal roof for the life of me however.

 

[Bullethead]

This is a bit complicated to explain. The best explanation is in Silvarret's tutorial on building spires and domes.

https://youtu.be/an_hNSfxkgQ

The upshot is, you make a pie slice of 1/8 the circumference then copy it around. Because the 8 sides are all at angles to the grid, you can't use gridded parts so have to build up the surface out of dozens of small non-gridded parts. So this roof alone will likely have close to 1000 parts when you copy it to all 8 sides. Still, it will look nice