Cedar Flashing

Looking at a Cedar Shake repair....Older roof, he does not want to replace. So....for the valleys and chimneys, is Copper the only acceptable metal? Or can I use galvanized to get through about 5 years....or a little longer?

.032 alum. is good. Copper is great also for the look. are they CCA treated? Freedom Grey is a good choice or TCSII when you can get it. Revere will be starting production again first quarter of 2015.

Turns out after meeting him yesterday we'll be replacing the sections completely...no patching.

Now....what metal to use? B)

Here in the NW, where until 20 years ago shakes were king, steel flashing was used about 99% of the time, about half painted, half bare galvy. Copper is used rarely and then only to add bling, not because of some perceived chemical reaction between cedar and metal.

Even though there used to be numerous aluminum plants around here because of cheap hydropower, it is extremely rare to see it used as flashing. In fact, if anyone uses it, it means "I buy my roofing supplies at Lowes."

Turns out after meeting him yesterday we'll be replacing the sections completely...no patching.

Now....what metal to use? B)

Repairing shakes that are installed at double coverage are fairly easy to replace. But if installed at triple coverage their very challenging because you have three rows of nails in each shake. If they are mediums they are not worth replacing as you will break more then you fix if they are old and washed out.

Gsm is fine. If you mean shakes, 24" W valley. If you mean wood shingles, 18" W valley. Replacing valley metal on an ancient wood roof is not a pleasant prospect. You can do it but if there's a lot of valley you'll be asking yourself "Why am I doing this again?" about halfway through if not sooner. The tie-ins are challenging.

Turns out there is bare aluminum in the valleys...which I thought was a no no....and it's like 20-25 yrs. old....and looking good

We always used copper for valleys and other flashings, however if your customer doesn't want to re roof sell him a NSF tune up Behr chemical sells a NSF product which cleans up the shakes and adds a few years to the longevity, replace the damaged shakes and nail down he loose caps and field shakes back in my days lol we used to get about 1/3 the cost of a new roof covering, pressure clean and scrub them suckers lol

You could use whatever you wanted to but how about factory painted aluminum? Just be sure it's not the thin cheap stuff. I like to use 6 inch gutter coil. ( 15 inches wide ) for all my flashing. Cost about one dollar a foot here.