For a good straight fascia, add an extra 20 mm or so to the tails of all your rafters (total length).
After they're up, you can flick a line to mark and trim the tails in a nice straight line, to make up for any ridge warp or marking, cutting and fixing errors.
All running measurements are 'and on', from start point to near side of rafter.
Running Ridge: Mark out
Running Wall: Mark out
Left click, release then drag to measure at scale in diagram below - Enlarge diagram scale for more accurate measurements.
Rafter Detail (new window)
If you're cutting concrete, stone or ANYTHING
and there's DUST - DON'T TAKE THE RISK
Don't cut it, or cut it wet so there's NO DUST
- Silicosis Sucks