Minimum pitch for standing seam copper roof

Guest User
12/1/2008
I've received two estimates from reliable contractors for replacement of a 15'x17' roof. I'm inclined to use copper because I've been told it lasts a very long time and needs virtually no maintenance, and I plan to have a deck installed on top of this roof in the future, so no-maintenance is key. One estimate is $11,350 for 16 oz. copper with standing seams. The other is $13,786 for 20 oz. copper with flat seams (this contractor says the pitch is too low for standing seams). Questions: 1. It appears the industry standard minimum pitch for standing seams is 1/4:12 or 1/2:12, depending on which resource you consult. What is your view? 2. I'm told that standing seams on a roof that's too flat will create ice damming problems. What is it about standing seams that makes ice damming more likely than with flat seams? 3. What's your view of copper as the roofing material under a deck? Can you recommend something better? 4. This roof is right under a line of windows in the wall of the floor above. Will copper reflect sunlight to such an extent that the room will be noticeably warmer (which would not be good)? 5. Which is better - 16 oz. or 20oz? The roof will only be walked on once a year for access to equipment on the higher roof above, and then when the deck is installed. 6. Given this situation, do you have any other advice or suggestions for questions I should ask the contractors? Thanks very very much for your help!!! I'm just a lowly homeowner who's struggling to figure out what to do. Nell
Guest User
12/3/2008
Hi Nell, (sorry for my English, I'm from Germany :) ) The minimum pitch for standing seam roof should NOT be under 1-1/2:12 better 2:12. The issue for that is not the ice damm, but the rain water. Standing seams are generally "rain-proof" but NOT "water-proof". That means: when the rain water CAN flow down after falling on a standing seam roof is fine. Under 1-1/2:12 pitch water will most likely stay and accumulate on the roof and enter the roof through the seam. Soldered flat seam roof: Please do NOT waste your money with that!!! We mostly tear off 2 or 3 year old very expensive soldered seam copper roofs, because they are just a mess (sorry) and only last till the first or second winter/summer change. The temperature change WILL rip the solder joints. I promise! We mostly recommend than rather to rise the pitch and put double locked standing seam roof on it. OR, but now I speak against my self, put a Sarnafil flat roof on it. (metal roofs are NOT good for flat roofs) Sarnafil would be better for your deck plan above the roof anyways. The thicker copper, to answer your other question, is for sure better BUT the 16 oz. copper ist the mostly used material thickness AND it is absolutely fine AND enough for using it for roofing. (The 20 oz. although will be than better for clading because it is more rigid and wont get that fast wavy) I hope I helped a little Have anice day Erno for any questions: [email protected] www.copperexclusive.com
Todd Miller
Classic Products, Inc.
12/3/2008
Thanks for your questions. Snap lock standing seams should not be used on roofs under 1.5 or 2:12. However, there are many mechanically seamed standing seams that are very appropriate for lower pitch roofs -- usually down to about 1/4:12 Most flat seam products will have soldered seams to make them watertight even on a flat roof. The product should work under a deck. But, if the deck is from treated lumber, chemicals from the treated lumber could exacerbate the aging of the copper. The copper will be shiny and reflective at first but that will diminish quickly as it develops patina. 16 oz is probably fine for what you have described.
Guest User
1/9/2009
you need to check with your state code not just the man recs on what pitch in florida the pitch min is more than say alabama so check on that a well.
Todd Miller
Classic Products, Inc.
1/14/2009
Thanks.
Guest User
11/17/2009
If you plan on putting a deck over this roof, i would recommend using a flat seam roof. they are more structural sound because everything is "locked" together. I live in the midwest, where temperatures range from the 90's to below 0 and if the roof is installed correctly, it should not open. the most common mistake i see with these roofs is poor soldering practices. You need to make sure your contractor is "sweating" the seams, not just cover over them. also, your panels need to hook into each other rather than just lay over with rivets. I have installed approx. 80 flat lock roofs and nearly 100 standing seam roofs. i personally would not put a standing seam on anything lower than 3:12 just because the water infiltration possibilities. especially if you plan to put a deck over it
Guest User
2/11/2010
Hello,i have been installing flat seam copper roofs ,standing seam roofs of many different materials.If a flat seam copper roof is installed properly ,soldered properly the roof could last 80 to 120 years.
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