Zero Shingle Overhang on D/DL Drip Edge on 7 in 12 Pitch Eve?


#1

The real question do I tear off a couple hours work and redo with 1/2 to 3/4in overhang?

Arch Shingles.

NOTE: I did a test pouring water on the shingles to see how it shed - it shot off the top of the shingle and never even contacted the starter strip. But as the shingles wear and their surface oil content lessens, the water will wet the shingles, stick to them, and the who knows where capillary attraction might take it.

I do know for a fact that on a very low slope commercial roof (but not flat), the water will wrap around the drip edge lip and run down the vertical portion onto the fascia if it is touching.

If the slope is high enough, zero overhang is not a problem - but what is that slope?


#2

What is the fascia made of?


#3

Vinyl fascia snapped over F-channel nailed to wood,

While it’s a legitimate question. I tore it off just to be on the safe side. NOTE: this was on one side of a chimney so I would have had to do the other side the am for even shingle courses when they joined above the chimney.


#4

If you feel so strongly that normal wear is going to cause capillary action and cause water to enter the system you have 2 choices that are much cheaper that tearing off roof , +1 you can simply install a bead of black jack mastic in a caulking tube 1/2 inch under the 1st run of shingles ,which once cured isn’t going to allow a drop of water to be pushed uphill and into the system .,or you can tear out the existing drip edge and install a custom drip with a 5 inch roof flange edge and the 6 raised dimple lines on the flange edge will make it impossible for " normal non nice dam capillary action " to force water past all 6 raised lines on the drip edge flange ,if it were me I’d install a continuous bead of black jack under the 1st shingle and basically weld the shingles to the drip edge ,at $3 a tube and 25 linear feet per tube it’s your best option .


#5

I’m not worried about water finding it’s way up the roof - the amount of overhang would have no bearing on that.

I’m concerned the water will not shed from the shingle tails (drip edge lip) but instead, the water may wrap around the lip and then drip off the down leg of the drip edge which might end up running down the fascia board.


#6

The problem is that if the shingles were not installed with an overhang you can’t just remove the first course and move it down a 1/2" - 3/4" or the next course will not cover the nails of the one you moved.

If your roofer made the first course short like I almost always do you may have some leeway to move it to get an over hang otherwise you will need to add a course which will leave you with 2 short courses at the bottom of the roof.

The reason I asked what the fascia is made of is because if it is aluminum, vinyl, or some other metal it’s not likely to rot like cedar will, it will stain & discolor though.


#7

do it right the first time


#8

So many “roofers” do that because it is easier I guess. That and they don’t know any better!
If no overhang of the first course the water will
curl back and drip down the fascia and get behind gutters (if they have gutters). I’ve seen rotted fascia many times which could have been prevented VERY easily by hanging first course over drip edge.