Locating rafters

hi everyone

i have a job coming up this weekend and i have to put in two whirlybirds and replace a lot of blow offs

here’s my question

is there a better way of locating the rafters i usually just look in the attic for a reference point and to see how far apart the rafters are is there a better way of doing this and i don’t have money for a stud finder and this is a hip roof at about 13 square.


ok, sorry if that was rude.

If you cant figure out how to do it from the roof, just get in the attic, and drill a hole from the bottom side, then get up on the roof and find the hole.

but tearing off the shingles and simply looking at the decking… along with knocking on the wood or stomping on it with your foot should make it pretty obvious.

Well i dont think i can say much other than put a nail on center of the rafters where you want your vent. 16d would work.