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Norman
Posted on Friday, August 10, 2001 - 03:03 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Hi. I got the impression from the Slate Roof Bible that I can mix different metals during restoration work as long as the metals are NOT IN CONTACT. For example, I want to replace the ridge with copper ridge and the valleys with copper sheets. As long as I use copper nails, will this be okay? The slates on the 100 year old roof have been nailed with hot dipped galvanized nails, the valleys have been tarred over-- I would guess terne metal/ steel/ or lead is underneath for the valleys and the same with the ridge (any advice for distinquishing between terne/galvanized steel /lead? What type of nails do terne metal and lead sheets take, ie. do lead and terne nails exist?)
The future-- potentially copper-- valley runs within 7 inches of a lead flashing chimney and about 12 inches of a raised aluminum skylight on the other side of the valley. I could "place a layer of roofing paper, roof cement, paint... between the metals."page243
I was also wondering whether the aluminum gutters would be affected by the electrolyte washing down with rain into the gutters and rusting them. Should I buy the ridge iron instead?
I was also wondering about retrofit snowguards. A copper snowguard could potentially rest upon the top of the hot dipped galvanized nail and rust it out which would be a bad idea? A galvanized snowguard would not last very long.
Thank you for your feedback. You are the best!!!
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John
Posted on Monday, June 03, 2002 - 06:21 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

avoid mixing of metals
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admin
Posted on Tuesday, June 04, 2002 - 09:04 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Use retrofit stainless steel snowguards on a slate roof with galvanized nails.
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Peter Young
Posted on Sunday, November 03, 2002 - 08:20 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I am installing a copper ridge roll on my slate dormer roof ridge.
1. What is the best or easiest way to adhere the copper ridge to the roof - can I use silicon or should I nail? Where do the nails go (near the peak of the ridge or at the lowest end of the copper)and how do I punch through the slate under the copper?

Also,is it OK to cover over the existing aluminum ridge flashing if it is not in the way (it' a simple "V" shape)?
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Joe Jenkins
Posted on Sunday, November 03, 2002 - 10:30 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Always remove the existing, old metal ridge before installing new. Nail the copper ridge with 2.5" copper nails (we use 10 gauge and we also sell them on this site in the store). Nail along the bottom edge of the ridge metal, between each slate (or, if only 6" wide slates, between every other). Caulk the nail heads with lifetime clear silicon. Usually, you can drive the nails through the slate, but the nails will bend on harder slates and you may have to use a 16 penny common nail to start the hole. On new slate, you may have to drill the holes, one drill bit through the metal, and a separate masonry drill bit (3/16") through the slate.
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Peter Young
Posted on Monday, November 04, 2002 - 11:32 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Mr J., thank you very much for all of your advice. I successfully, resided my dormer, repaired some slate, and installed a new ridge roll using all of your advice and that of others on your message board.
By the way, is there such a thing as lead coated copper ridge roll that would match the color of aluminum? Is aluminum almost as good as copper? (I now have a mix of copper and aluminum and it doesn't look too good!)
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joe jenkins
Posted on Saturday, November 09, 2002 - 01:20 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

You would have to have the lead coated copper ridge custom made. I don't like aluminum ridge because it tends to be less strong and people often nail it on with iron nails - the nails wil rust because of the action of the aluminum, then the ridge gets loose and blows off.
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Peter Young
Posted on Friday, November 22, 2002 - 11:19 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Would you recommend that I paint the copper to match the aluminum that is everywhere else? Or, is there a way to make the copper tarnish immediately so it doesn't stick out so much?
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Walter Musson
Posted on Friday, November 22, 2002 - 11:37 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

Peter,
I would recommend replacing the balance of the ridge metal with copper so it's all the same.
In that way it could all weather in the same.The aluminum won't last as long as the copper ,so why not replace it now instead of trying to make the copper appear to be something it is not.
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Tony Foyle
Posted on Wednesday, March 03, 2004 - 04:19 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I've two flashing questions:
Is it true that copper valley flashing should not have any underlayment under it? Why so? Should copper have rosin paper placed under it if there is underlayment already present?
I'm also wondering how bad galvanic corrosion is between copper and old terne metal. I may change my valley flashings (house in Erie PA) to copper, but the valleys drain onto a 1:12-slope terne roof ... if I keep that terne seamed roof well painted with FeOxide paint, will galvanic corrosion not be a worry??
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slateworks
Posted on Wednesday, March 03, 2004 - 08:41 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

You do not have to have any underlayment under your copper valley-Although if you wish to install Underlayment such as Roofing felt or Rosin paper this will not hinder the performance of the Copper over it's lifetime..It is not necessary to install Rosin paper over an existing Underlayment.What we try to do during a valley replacment(Open valley-3 to 4" of metal exposed on each side of center),After you remove the slate,If the felt paper has any life left,We cut the paper about 1" wider than the existing valley-Remove the old metal-Take a wonder bar and remove as many nails as possible so a piece of felt can slide up under the existing felt,We will bend most of our Valleys 9 or 10" up each side(18" or 20"wide overall)-Install valley-Then cut strips of felt to slide up under existing felt and extend onto to the top edge of your valley by 3 or 4"...If the underlayment is shot ,we still add a strip of felt that slides up under the Slate and over the top edge of metal valley.--You can also replace your valley without any felts without any problems-Just choose a method that you are comfortable with-Some like to install felt under the valley to protect it from old nails and wood from working against the metal and or telegraphing thru-We decide this once we remove the old valley and are able to view the overall condition of woodwork and nails ect...--I think as long as your roof is painted you do not have to worry about a reaction from the copper run off onto to your Terne tin roof.Just yesterday we removed copper valleys that were 65 years old that ran onto to a painted terne roof that is also 65 years old and shows no corrosion from copper valleys.
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Walter Musson
Posted on Thursday, March 04, 2004 - 05:19 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I always use 30 lb. felt as underlayment.I can't think of any good reason not to.
I do like Ron talks about using felt to cover between slate to over top of metal valley to help conduct water onto the metal.
I agree that galvanic reaction is not a concern for this application.
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Joe Stoffel
Posted on Sunday, October 30, 2005 - 11:25 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Moderator/Admin Only) Ban Poster IP (Moderator/Admin only)

I have several questions which I hope you can answer for me. I have a french tile roof that I want to install a power roof vent(temp-humidistat control). The vent has a square base made of aluminum and I want to mount that base to the decking then cover it with ice and water dam then cover that with either copper or lead for flashing. What metal reactions do I need to protect from and how? We've using 2.5" stainless steel ring shank nails and putting the tiles directly onto the decking. I'm also using Flexim instead of motar.What gauge copper should I be using? The gutter flashing is also copper but I have seamless aluminum gutters, am I heading for problems down the road? Any suggestions? My previous roofer took off with my materials (nails, copper, etc.) and $10,000 that I had paid him. He now has a lien on his house! Thanks

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