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Last year, I had a new fiberglass shingle roof installed by one of the better roofing companies in my area. Overall, I am happy, but I'm not sure that the drip-edge was done correctly. It seems that water will wick up under the edge and potentially cause rot (I live in a humid area).

I am considering attempting to bend the edge up, so it is more like the previous drip-edge. I think that if I make a wood wedge on a table saw about a foot long, I can push it up under the edge and press another piece of wood at the existing crease to increase the bend. I know that it will flex enough to get a wedge in, since I put temporary spacers under the edge so I could get paint under the edge (roofer left any replacement fascia unpainted).

Is this a good plan?

I pointed out my concern to the roofing company owner, he disagreed. I wasn't sure enough to argue much.

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  • The goal is to install the drip bridge properly,a properly installed drip edge will prevent wicking. thisoldhouse.com/how-to/testing-drip-edge-installations-roofing – Alaska Man Oct 1 '19 at 18:43
  • @AlaskaMan - Thanks, nice video, better than anything I could find. I suspected that it wasn't done right. Still don't know if the roofing company doesn't know better, or won't admit to the mistake. None of the houses in my area have a gap like the video. But in most, the aluminum will touch the fascia at the "kick" (crease) near the bottom and it will angle away far enough to prevent wicking. An 1/8" space at the bottom is probably enough to prevent wicking. – Mattman944 Oct 1 '19 at 21:21
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This might technically be a valid concern, but millions of homes have drip edge installed exactly like yours. In fact, I've never heard of it being installed with a gap. The contact between the lower flange and the fascia actually supports the upper surface of the drip edge form. Without that support you'd see sag, as the metal is quite flexible. I wouldn't be surprised if it rattled in the wind.

If you want to satisfy your concern, I'd insert some plastic clips (think tiny clothes pin or paper clip) along the bottom edge at say 12 inch intervals. This would serve to raise the metal off the wood while maintaining support as I've described.

Frankly, a better solution (if durability is your primary concern) would be to just install brown fascia wrap. It's relatively inexpensive and easy to work with. You already have maintenance-free soffit, so why not that as well? Of course, I understand reluctance to do so if you have wooden siding. I have cedar siding and fascia with steel soffits myself.

  • My proposal will still have the aluminum touching the fascia where the crease is. It will angle out from that point. I should have made that more clear on the diagram. – Mattman944 Oct 1 '19 at 18:12
  • Fascia wrap is a good idea. I didn't realize that you could buy it pre-made. The house is stucco, it would look fine. – Mattman944 Oct 1 '19 at 18:17
  • I'm confused by your first comment. The lower flange already has a kick on it. What would you change? – isherwood Oct 1 '19 at 18:20
  • There is already a slight bend about 1/2 inch from the bottom, what I am calling the crease. It is about 20 degrees. But, the portion just above the crease is not parallel to the fascia, it has about the same 20 degree angle, so the bottom part (below the crease) is about parallel to the fascia. I am proposing increasing the bend at the crease from about 20 to 40 degrees. – Mattman944 Oct 1 '19 at 18:41
  • Maybe the photo is deceiving. It looks like there's already a good 1/8" or 3/16" gap at the bottom. – isherwood Oct 1 '19 at 18:47
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No. Opening up the joint creates increased opportunity for bulk water entering the wall system driven by rain. Capillary action is a less likely source of bulk water penetration. The joint widens behind the metal, the wood’s rough surface lowers surface tension, and the depth of overlap gives gravity a lot to work with.

While a properly formed positive drip edge formed from a wider piece of metal would have been better, the improvement would be mostly the wider material. Wider flashings simply provide more protection. One reason drips are associated with wider flashings is complex profiles add stiffness. The stiffness reduces oil canning of broader sheet metal surfaces.

The construction looks pretty typical for a reasonable residential roofing job and the roofer’s experience with local conditions and intact reputation count a lot more than lay roofing theories. A good rule of thumb is don’t add holes to working roof systems (or enlarge existing holes).

If a large volume of water is coming over the edge of the roof, gutters and downspouts might be warranted.

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I like the idea of creating a “drip edge” so the flashing is not touching the fascia board, but I doubt you can make a “clean” break in the middle of the vertical leg of the flashing.

Typically there’s a “kicker” (out) near the bottom of the vertical leg of the flashing. Trying to make one now (with the flashing in place) will be difficult to keep it straight and “clean”. I’d guess there will be bumps, dents, etc. from manually bending the flashing in place.

I’d try bending the flashing out where it bends over the roof edge. I think you could push a flat steel plate (perhaps about 36” long) up to the top edge and then pull the vertical leg away from the fascia.

The downside is that wind could blow rain up under the flashing. Do you live in a high wind area?

  • High wind? Florida, windy during thunderstorms and hurricanes. – Mattman944 Oct 1 '19 at 18:19

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