On Friday, November 8, 2019 at 6:35:18 PM UTC-5, Dan Espen wrote:
Clare Snyder writes:

On Fri, 08 Nov 2019 12:38:06 -0500, Dan Espen
wrote:

writes:

Hello, my house was built in the 80s and is located in the NE United
States. I recently had a handyman in to do some work outside replacing
some rotten wood and he said it looks like some corners were cut when
the house was built, the builders did not install 'flashing' around
the edges of the roof, and the roof doesnt overhang the siding in many
places. Also he said the house doesn't have a 'membrane' layer, which
is is a more recent requirement. As a result water can get behind the
siding and cause rot. He thinks that the roof shingles need to be
replaced in order to install the flashing. I think the shingles are in
pretty good shape. Its not the original roof, but it is at least 10
years old. I dont want to get a new roof if I dont need to. He knows
a roofing guy who will take a look, but I plan to get an independent
roofer to check as well. Does the bit about flashing sound correct?
And can flashing be installed without replacing the whole roof? Thanks

You don't need to replace the whole roof.
Depending on the age of the roof, you may want to do that if you're
having work done.

To install flashing, you need to remove the row of shingles between the
wall and the roof. Maybe one or 2 rows, that's all. More important,
yoou need to remove siding to get at the wall/roof interface. The flashing
bridges that space.

I'm having that kind of work done right now.
It's not "flashing" that is hios problem - it is the drip edge.

see https://www.jlconline.com/how-to/fra...-and-the-irc_o

Now that you point that out, I agree.

Drip edge isn't 100% necessary, you might get some rot on the edge of
the roof but it shouldn't cause any leaking.

Drip edge should be installed with ice barrier membrane.
That's 4 or 5 feet of shingles to remove so might as well
replace the whole roof if you're going for it.

Drip edge and ice barrier are two different things. Unless the OP is
actually having ice damming problems, why tear apart the roof? You
can slip drip edge in under the existing shingles.





I wouldn't tear off a roof just for a drip edge.
It's easy enough to replace some plywood the next time
you need a total shingle replacement.

Just had 4 plywood sheets replaced in the work I'm having done now.

--
Dan Espen

The big info lacking here is what was rotted that lead to discussion
about the roof. If it's rotted fascia boards, which it sounds like it
could be based on what the OP has said, it can be fixed with drip edge
or longer gutter flashing, that gets the water into the gutters, not
running behind it.