I’ve been studying the roofing courses and reading installation instructions. It appears to be a topic of much debate. There’s a thread to this topic many years ago.
Owens Corning recommend when drip edge is used to have the shingles flush with the drip edge on the rake. GAF recommends up to 1/2 inch overhang. When I did roofing we always had the 1/2 inch over hang on the rake regardless of brand, guess I should have read more instructions back then.
Does anyone address this with their inspections?
By code in my area underlayment is not required on 4/12 and above. But installation instructions state that the roof should have underlayment. I inspect to installation instructions in this case.
Attached is a photo of a new construction with no underlayment at the eaves. I’m in southern Indiana, ice damming is uncommon. But that doesn’t mean it doesn’t happen.
Personally, I think you should use better terminology (not your fault specifically) for what you are explaining/asking. Example: A “Rake” does not have a “Drip edge”… it has a “Rake edge”. Water does not intentionally “drip” off of a “Rake”, thus the difference in design.
So, with that being said, IMO, the shingle overhang (or not) on a “Rake edge” is dependent on the type of rake edge flashing installed…
Type D flashing should have the shingles cut to the edge of the flashing. Nosing and Grip edge flashing should have an overhang of about 1/2 to no more than 1 inch. Some manufacturers may be more restrictive with that measurement.
Note: the type D flashing design affords support to the shingle overhang to eliminate damage, thus any overhang is considered excessive and defeats the purpose of the flashing.
Flush to maybe 3/4". Maybe 1" if it’s heavy, high-quality shingles. It’s not crucial, but you don’t want them to hang over so far they start to droop when they get hot. As Jeff pointed out, the metal profile can vary. You want the edge metal over the underlayment at the rakes.
I call it all drip edge if it goes on the edge of the roof. :mrgreen:
