Newer Illinois Requirement

Also I believe that the NRCA has had that verbage for at least 15 years for all roofing installations, not just in Northern States. They don’t recommend it, however, all shingle manufacturers say it is acceptable with an ice/water shield installed underneath.

I, personally, like the woven method. I just can’t improperly say that a closed cut valley is wrong.

Jeff

Pretty sure the Radon guys put stickers up with phone numbers and easy to check if for some reason we play AHJ .

Cut valley may simply be another call out on new roofs to add to our punch list of items not proper but functioning for seller vs buyer to haggle with.

My biggest worry today on the 1890 3 flat will be getting hit by lightning.