My contractor attached a standing seam copper roof with galvanized nails (I found some aluminum nails laying around as well). My understanding is that these are incompatable metals.
Advice?
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Well, can water get to the nails?
If the answer is yes, then it's just a matter of time before galvanic corrosion will set in. This will be particularly a problem in coastal areas where the salt content in the air is higher.
My roofer only used copper nails to attach the gutter. I presume that he had good reason to use a high-cost fastener instead of a low-cost alternative. I hope your roof doesn't have to be redone - that'll be a lot of work. Try contacting the company that supplied the roof materials or the copper metal association for additional info.
Edited 7/14/2005 4:26 pm ET by Constantin
> ... or the copper metal association for additional info.
http://www.copper.org
-- J.S.
It's a matter of time before the galvanized nails deteriorate. How much time that is will corespond to how much moisture there is where the nails are. Might be a long time, might not. I'd be concerned about other questionable methods used by this guy if he cut that corner. Good Luck.
edit: Can you see the galvanized nails? Is anything face nailed?
I'm not green anymore.
Edited 7/14/2005 4:38 pm ET by cu
thanks for the help on the copper roof.All in all he did a nice job, no face nailing and meticulous soldering. I almost think he just didn't know. His family has done standing seam roofs for 2 generations. This was their 3rd copper roof.We live in western Virginia, humid in summer but temperate overall.Do you think I should ask for a settlement with his insurance company? Hate that kind of stuff. Still, this roof should last a while.thanks, asher
Do you think I should ask for a settlement with his insurance company?
How big is this roof? Did you sign a contract and if so, what did it say?
Here's the legal part of mine:
ALL MATERIALS TO BE AS SPECIFIED AND ALL WORK TO BE COMPLETED IN A MANNER CONSISTENT WITH STANDARD INDUSTRY PRACTICES AND PREVAILING BUILDING CODES. ANY CHANGE TO THE ABOVE DESCRIPTION OF WORK OR TO THE SPECIFIED MATERIALS INVOLVING EXTRA COSTS WILL BE CONSIDERED A CHANGE AND WILL BE EXECUTED UPON WRITTEN CHANGE ORDER. THE OWNER SHALL MAINTAIN PROPERTY INSURANCE FOR ITS FULL INSURABLE VALUE. CONTRACTOR WILL PROVIDE LIABILITY AND WORKER’S COMPENSATION INSURANCE AS REQUIRED BY LAW. THIS PROPOSAL SHALL BE VALID FOR THIRTY (30) DAYS FROM THE DATE OF SUBMISSION. WORKMANSHIP WARRANTY TO EXTEND ONE (1) YEAR FROM DATE OF FINAL BILLING. PAYMENT IS DUE ON RECEIPT OF INVOICE. TWO PERCENT DISCOUNT IS ALLOWED IF BALANCE IS PAID IN FULL WITHIN TEN DAYS. A FINANCE CHARGE OF TWO PERCENT PER MONTH IS DUE ON UNPAID BALANCES.
meticulous soldering. I almost think he just didn't know. His family has done standing seam roofs for 2 generations.
There should be little if any soldering on a standing seam roof. Around penetrations is about the only instance I can think of. If this guy's family has been doing SS for two generations, then they probably should make good and do it right. Not knowing is not an excuse.
Last question: Did you pay for a properly done copper standing seam roof or did you pay for a substandard job?
The problem as I see it, is you've got concealed fastners that are going to deteriorate at an unknown rate, but will deteriorate. After they deteriorate, , gravity might hold the roof in place for 60 years or a strong wind might take it off in five.
If I were you, I'd ask for a redo on this one. Good luck.I'm not green anymore.
Thanks for your input. Not looking forward to this fight.=asher
Aluminum is even worse than galvanized with CU. Stainless is pretty good.
I'm working on a roof which has been on for 65 plus years-asbestos over cedar shingles.The copper valleys were fastened with galvanized nails at that time.There is not much evidence of galvanic reaction on these nails over this length of time.I'll take a picture tomorrow and post it here for you to see.
We know now that you should always use fasteners of the same material as the sheet goods,but back along I think they used what they had.
I guess my point is that we know it's not exactly right but it will probably last a long time anyway.
I guess my point is that we know it's not exactly right but it will probably last a long time anyway.
For the sake of argument, I'm gonna call you out on the "probably" in that statement. I've seen similar situations where galvanized nails thru copper had lasted a long time. I've also taken apart chimney flashing that had not been in place for a year where galvanized nails were used. It was an amaturish job and I suspect the steps were nailed with gun nails, but they were so deteriorated it was impossible to tell for sure.
I asked this question earlier and it didn't get answered: Did he pay for a first class job or did he pay for a halfassed job? Using galvanized nails in contact with copper is not acceptable if he paid for and was expecting excellance. If he took the lowball price, he's probably getting what he paid for. We don't know these details.
I think I'd ask for a mulligan.
I'm not green anymore.
I tried for an hour last nite to post some pictures of the copper valleys with galvanized nails,with no luck.I resized my pics to 760x480 with Irfanview and tried to upload them with no success.I'm on a dial up connection so maybe that plays a role.
I'm going to try again today.
Be glad to look at them. I wish I'd taken some pics of the flashing in question. As long as there's no h2o in the equation, there's no problem with putting galvanized and copper together. But, the fact is: water is usually present in a roofing situation. I'm guessing the picture you're gonna show me is of a wide valley on a 12/12 roof. That's a different animal than a 4/12 roof valley in a copper roof in heavy snow country. I'm more concerned with condensation on the bottom of the roof than surface water.
I've seen galvanized downspouts used on copper gutters fail in a year or so. They deteriorate where they meet.
Cheers.I'm not green anymore.
It is a steep roof but not to wide a valley.
You're absolutely right that oxygen and water must be present for corrosion to occur.
I can put some shots on Shutterfly and e-mail to you.I tried again this morning to upload and it won't allow me to complete it.
Cu's not alone in his interest. I'm also dialup but have no problem uploading .jpg files. Must be something else going on. You could email pix to either of us to post if all else fails. That's how we all learn here. Examples, good and bad.
I went way out of my way to isolate stainless screws from the copper I sheathed my house with. Then did a small test at the end, which several yrs later shows no deterioration, even with considerable area effect. My not-so-scientific conclusion was that galvanic problems were less prevalent here, probably not so far from asher. But that's certainly not to say I'd consider glavanized. In fact, for the second house we sheathed this way, we went to copper rivets which also looked nicer.
Cu asked the pertinent question about cost and expectations. PAHS Designer/Builder- Bury it!
Thanks.
I'm not sure why my connection is having trouble,but in a thread a while ago I saw others were having difficulty too.
I've got a lot of shots I'd love to post-some from the Mansard slate work we're just finishing on author Stephen King's library in Bangor Me.
Sounds great. Maybe sysops will be able to help tomorrow. I posted a pic this AM, no problem. I'll try again.
Hmmmm. That was interesting. Got a very slow connection speed and mine wouldn't go after 2 tries either. Guess you can try another time when maybe they've got it fixed.PAHS Designer/Builder- Bury it!