How to fix gap between roof edge and fascia caused by pressure washing mistake?

Question

While pressure washing around a deck ahead of some repainting and repairs, I accidentally caused a new need for repairs. Using an 1800psi washer and 15-degree nozzle from 3-4ft away I sprayed in broad strokes the gutter and soffit to clear debris from it, while trying not to put water into the attic. Some of the spray went above the gutter and got under the shingles in just the right way to pull up some of the roof! I stopped spraying anywhere near there and tried to push it back down but it was not so simple.

Photos below show the problem area. The shingles are not loose, they all feel secure to the plywood sheeting below them. When I shine a flashlight into the gap I can see the ends of rafters and can see plywood splintered with roofing nails going through it. I poked at the wood with a knife and it feels solid, and it looks old but I don't see any black or green growth on it, so I think the attic is fine for now. Circled in red is a nail that connected the roof to the rafter, which has come out some.

I tried to firmly press the roof back down from a step ladder, which only helped a little. I took a few careful wacks with a rubber mallet, which helped a little more, but that was all before these photos. How to remedy the issue you see above? Ideally I want to just firm it back down, maybe I need to wait for a clearer day (storms expected today) and get up on the roof for better hammering. If this uplift cannot be undone, I figure better flashing would at least make it tolerable. The roof is relatively new, I think installed 4 years ago (before I got here), new enough that asphalt bits still come off the roof when shingles are disturbed.

I wanted a quick patch for now because we have carpenter bees and paper wasps searching out new homes and rain expected - both important to keep out! I have no spare flashing so I used tinfoil, and I'll keep an eye on how stormwater runs off this part of the roof, further patching if needed. Open to better quick fix suggestions if a proper remedy is not quick or requires a pro. (I don't know how bad this is, but I realize how important my roof and attic are.)

Answer 1

It's difficult to tell without seeing it in person, but here are a few ideas:

1. If you have attic access and can reach the rafter ends from the attic, you should be able to see the nail ends sticking out from the roof sheathing. Use a pair of vise grips to grab one of the nail ends, and pull the sheathing down. Or have someone stand on the roof while you work from the inside. Then install an L-bracket to hold the sheathing against the rafter. I like mend or tie plates for this, as they have many holes, and you can insert many 3/8" long wood screws (you don't want the screws sicking up and perforating the shingles, and you might need washers.
2. Using a flat prybar, lift the shingles at the end, and using a long driver bit, screw the sheathing against the rafters from the top. Then use roofing tar/sealant in a caulking gun to seal the starter strip again back against the plywood.
3. Get a roll of aluminum flashing, bend it length-wise at 90-deg angle and insert it below the drip edge and in front of the fascia board (with some luck, the installer did not nail the drip edge right at the end of the plywood.) This will last until it's time to replace the shingles, at which point you can nail the plywood against the rafters with galvanized 3" nails.
4. Put construction adhesive between the rafter and plywood, then place a heavy object on top of the shingles for a day, or until the adhesive cures. If the plywood has a lot of bounce (as it looks it has), the glue might not hold for long. But for ten bucks' worth of glue, it's worth a try. A good car mechanic once told me that you don't always try to fix things in the order or most likely -> less likely issue but from cheapest/easiest --> more expensive/harder

Answer 2

It is for a roofer an easy fix, for a DIY'er, a little more challenging.

The nails or staples holding the shingles down need to be removed. This best needs to be done in the spring or fall so the roof does not get too hot, so the surrounding roof doesn't get marred by the work done on the shingles. You will want to remove at least 3 rows of shingles. The thing is the 3rd row is also held in place by the nails in the 4th row, so that is where you start, using a prybar of the proper thinness. I prefer the Stanley pry bar that is yellow. it is thinner than the rest on the fanned end. This wil pick up the shingle at the nail or staple and, with practice lift the nail so it will not go through the shingle. Some will, but still pull the nail with the bar.

Wait a minute, got a little ahead of myself.

First I "loosen the shingles" by using the bar to lit the edges of the shingles from the lower course, over the whole area I feel I need to attend to. I look at places where the shingles meet the next one. They are about 3 feet long. Then knowing that bit of info I start removing the nails as described above.

Back on track..

If you look at the edge of the roof (where the shingles are cut to length), you will see how the roof is laid and why the nails need to be pulled from the 4th course, since the nails holding the 4th corse is through the top edge of the 3rd course. Hopefully ou get te gist of the removal of the rest, to remove th whole shingle over the rafter.

With the shingles over the rafter removed, you can run as many nails you need to get the plywood to stay down without the original nail heads popping up and poking holes in the shingles making a roof leak there.

Get the plywood down, it will not take a lot of nails at the end, usually 3 well placed 2 to 2 1/2" nails in solid wood will do about 6-8 inches apart. Screws will work too, make sure the heads draw in, proving they have a good grip. Most of the time...

Relay your shingles. Use roffer caulk to seal around any holes made by the removal of the shingles that were made UNDER the roofing course above. Any holes made in an exposed part of the roofing, replace the shingle.