"Synthetic Stucco Without Failures," by Mark Parlee (Dec/14)
Chrishoppepe: Great article, but I would like to comment on the counterflashing where a roof meets a sidewall. Photos 4 and 5 in the online version of the article show a nice rigid counterflashing above the step flashing. This will allow the shingles and step flashing to be replaced in the future without damaging the stucco. In photo 7 online, it looks like a peel-and-stick membrane was used as counterflashing, which would make it almost impossible to remove and replace the step flashing in the future. Please give roofers a break and make sure that roofing can be replaced in the future without removing the siding. This is true at membrane roofs, too, where the life cycle may only be 20 years.
Mark Parlee responds: Thanks for your comments and observations. You bring up a really important point that was not discussed in detail in the article, but warrants attention. You have to understand that these particular jobs were stucco. This one is a "direct applied" stucco, but the same applies to EIFS and traditional three-coat stucco as well. You can't remove the step flashing or the rigid metal counterflashing at the time of reroof without damaging the stucco. Stucco's too brittle and won't suffer any amount of flexing when you're trying to free the flashings.
Instead, we have to think forward, not only about the initial installation, but to the next roof. In anticipation of the roofer's work, we install the step shingles with a shim between each step, so you can slip each course of shingles in between the steps. We don't expect the roofer to interleave step flashing as he installs each course of shingles. Doing it as shown in the photo below (photo 4 in the online version of the article) takes care of job sequencing problems, as well. The step shingles are made from 24-gauge galvanized metal with a Kynar coating. This is both much heavier and much smoother than what is often used for step flashing, and if correctly installed, will allow the shingles to be placed after the flashing.
The condition shown in the photo is the exact same condition that will exist down the road after the roofers strip the roof. They will remove the old shingles from between the steps, without disturbing the counterflashing or the stucco, and will then lift each step to slide their new shingles in, just as we initially did on this project. I've worked carefully with my roofer (he's a good friend of mine) to figure this all out. It is a key detail, and I appreciate that you brought it up, giving us a forum here to provide more information.
It's also worth noting that the peel-and-stick membrane you see in photo 7 online is included by design. There is peel-and-stick on the roof deck that turns up the side of the wall. Laid over that are the step shingles, and over the kickout we place another piece of peel-and-stick as an added defense against all the water that will be splashing up once it hits the upturned edge of the kickout. Finally a rigid metal counterflashing will be applied to this, as well. Redundancy is the name of the game to keep that water from getting behind all the layers and rotting out the sheathing and framing.
