House architecture- How to extrude or move a face along an edge

Question

I am trying to create a roof overhang and am wondering if there is a way to move or extrude the fascia along the same angle as the roof? Is there a better way to create roof overhangs?

Answer 1

In 2.8, create a Custom Orientation from one of the sloping edges of your roof, by selecting the edge before hitting '+' in the header's Transform Orientations dropdown.

Then, GY will constrain translations to the direction of the slope, if the new orientation is in use. (Which it will be, by default, after creation.)

Also, following @AnthoJack's helpful answer here, it might suit your workflow better, (having set your cursor to 'Surface Project' and 'Geometry') to set your standard Transform Orientation to 'Cursor' for longer periods. Then you can effectively set up temporary Custom Orientations from faces of existing geometry by simply dragging the cursor over them.

(In 2.79, it's: Select the edge: hit CtrlAltSpace with 'Use After Creation' checked: use GYY)

Answer 2

After pressing G or E for grab/move or extrude you can press X Y or Z to have the action go along that axis. If you press X X, Y Y, or Z Z, the action will go along that object's local axis. It will likely be Z Z you need.

Edit: In 2.79, it extrudes along the face's normal already and you don't need to press anything.

If you want to move a vertex or edge that lies somewhere in the middle of your roof, you can press Shift V to move it along the same angle. Make sure you move the mouse in the direction you want it to slide, or it'll try to go along another normal than the one you meant.