Lead counterflashing in contact with steel flashing???
I’m overseeing the replacement of the roof on a client’s 100 year old Victorian in central Vermont. My masonry sub rebuilt the chimney from the roofline up and installed the typical lead counterflashing. Now my roofing sub is calling out a red alert, warning that there may be corrosion issues between the lead counterflashing and his steel flashing. (He’s using Englert 24 ga steel with the Kynar coating, and points out correctly that Englert’s warranty is voided if water drips off of lead flashing onto their product).
My roofer wants me to have the lead counterflashing replaced with the same steel as the rest of the roof. Seems like lead is about all I’ve every seen used for chimney counterflashing, –so I’m surprised at this late date to suddenly learn that it’s not a good material for this application.
Is this really a problem? Anyone else had this issue come up?
Thanks, –Brian Abbott
Replies
Better stick with the kynar warranty!
Kynar finishes have a nice warranty, and I would do nothing that jeopordizes that warranty. Why doesn't the roofer handle the flashing himself? Around here, roofing subs are always responsible for the flashings. That way if there's a leak around a chimney, or whatever, you don't have two subs to bicker over who's fault it is.
The roofer is indeed handling the flashing (which is typical here, too, as in your area). The point I wanted to investigate was his request that I engage him to change out the brand new lead counterflashing for steel. At the end of the day I guess that's where I'm headed, --in order to preserve the warranty, --but I wanted to bounce it around with some others first.
I do wish my mason (who is generally excellent) had been aware of this issue and brought it to my attention. Then I wouldn't be needing to have someone change out work that he did just 2 weeks ago.
Brian
I wouldn't be too hard on him. He's a brickey after all, not a roofer. I wouldn't expect your roofer to know a common bond from a Flemish bond.
If the mason installed the lead, it's likely "through" flashing which you can't replace without cutting back into the chimney. If you're "overseeing" the job, it looks like you had an oversight.
Grant
In your opinion, is water dripping off lead flashing onto Kynar painted steel a problem? Will the paint protect the steel?
I'm not sure, David. There shouldn't be any problem between the lead and steel. It must be the lead/kynar reaction and my gut feeling is that it's more of a stain issue than a failure issue. But I don't really know. DanH will be along soon and clear this up.
We don't have
a lot of stone chimneys with lead flashing here, but I know of at least a few. We have lots of painted metal roofing and I can't remember ever seeing anything that struck me as an issue where the two were combined.
Sounds like a "just in case"
Sounds like a "just in case" clause to me. I wouldn't be too worried about it. Worse case scenario is there's no warranty on the panels the lead runoff crosses. Don't see how it would void the warranty on the rest of the roof. But warranties are tricky sometimes.
The roofer is paranoid
Is he doing a metal roof or is he just using the kynar flashing in a shingle roof? if the latter, he can just switch tolead flashing.
But foir the record, on my house, I have a kynar coat steel roofing and chimney flashing, with a lead counter flashing since 1996. Not a hint of problem from it.