can't adjust roof overhang

[vanderloo5]

Can anyone tell me why I am unable to adjust my roof overhang. I created a new family type from "generic 12" only to change thickness to 4". When I select any perimeter line, the overhang box is greyed out. Surprised there is nothing for overhang in Roof properties.
Thanks,
Phil

[patricks]

Overhang is determined by the roof sketch lines, which is why there is no "Overhand" parameter in the roof's properties. You could use any roof type for any number of conditions, including overhang conditions, parapet conditions, flush roof/wall conditions, free-floating roof (supported by columns only) conditions, etc.

The "Overhang" dimension you see at the top of the screen is only used when you use Pick Walls to create your roof sketch lines. These sketch lines are "hosted" by the walls, and so you can specify an overhang dimension, either from the wall's finished face or the core face.

If the Overhang box is grayed out, that means the lines are just sketched with no relation to any actual walls.