On Jul 13, 9:14 pm, "Eigenvector" wrote:
Are roof angles necessarily standard? I ask because I'm going to be working
on the rafters and need to cut an angle piece to fit in beside the 2x8
holding up the roof.

There's no standard. Consider them the MSRP of construction.

I measured it out and came out with 9 inches over, 2.5 inches up which
should equal ~15.5 degrees for the roof angle. I'm not interested in
perfection, it just has to fit reasonably, but if I can get it exact it sure
would be nice. However 15.5 deg doesn't match a 3 in 12 or 4 in 12 pitch
more like 3.5 in 12. That's why I'm asking if roof angles are standard, or
at least WERE standard in the 1960's.

Construction drawings usually show a pitch, such as 7/12 (read 7 in 12
- rise to run, or 7 pitch), and the drawings are _usually_ followed
with some degree of accuracy. The pitch can be changed for a number
of reasons, such as the framer realizing that a slightly lower pitch
means he can buy 2' shorter rafters - that can add up to a fair
savings and the architect should have picked up on that.

I think you should lose the torpedo level and buy an electronic level
(yes, I am superb at spending other people's money) or put the torpedo
on a framing square and measure the rise

Just for clarification, my attic is ridgepole construction, 2x8 supports for
the roof, every other truss has a 1/2 x 10 board connecting the 2x8
supports. Weird construction, doesn't look sturdy at all in my eyes.

Those 2x8s are your rafters. If the 1/2(?) x 10s are about a third of
the way down from the ridge they're collar ties. That's fairly
standard construction, though the 1/2" is odd and the 10" is too.
Collar ties are not infrequently made out of whatever is left over,
but those are some odd leftovers.

R