I need help on the pros and cons (mainly cons) of using the above type of system for a K-12 school. My dear designer has found a detail from VM Zinc for a horizontal standing seam panel that he is in love with and I have reviewed in the info and so far I am not comfortable with the proposed detailing. I am trying to get in touch with rep, but in the meantime has anyone done such a system?
Try Follansbee at following web site:
Thanks Richard, but I should clarify. We want to use this in a vertical wall cladding system not roof. I called Follansbee and they only do roofs.
Julie:
I did some horizontal panels (with standing seams) some years ago – you might think of them as a “vertical Bermuda roof”.
the joints need to not be welded, and folded over so that they can move easily because in that condition there will be some movement. Detail the wall as a rain screen so that you aren’t assuming that the metal panels will keep water out – in fact, I would assume that the wall will take in a lot of water. You need to watch the panel length so that the expansion is kept under control.
The University of Cincinnati completed a new building clad in zinc about a year ago. Construction seems to have gone quite well and I have heard of no problems with the wall systems. This link will take you to a page with descriptions and photos:
http://www.uc.edu/news/NR.asp?id=1598
Be careful. One reason we see so few zinc roofs is that they can be vulnerable to internal corrosion (“white rust”) due to condensation or other moisture on the underside. Capillary action can attract moisture to and hold it against the inside surface, where it does its damage insidiously. Detailing so that area is ventilated can be critical. I would think zinc wall cladding would have the same potential vulnerability. Would the designer consider another material?
Two years ago I specified a similar system. Here are the other two manufacturers, besides VM Zinc we listed:
Contrarian Metal Resources; 20120 Route 19, Suite 207; Cranberry Township, PA 16066, Phone: 724-779-5100; Fax: 724-779-5112.
RheinZink America, Inc: 835 Cedar Terrace; Deerfield, IL 60015; Phone: 847-444-0040; Fax: 847-444-0020.
I concur with comments by Anne and Robert. Also consider pre-approving and listing fabricators in your specification, along with mfrs.
I spoke with the VM Zinc representative and discovered that they are convinced that the detailing with no rain screen is doable because their panels have a backside coating that protects the zinc from internal corrosion. They give a 30 year warranty for the coating and of course they are the only manufacturer/supplier that have such a warranty. They further say that in the vertical application that the metal panels will keep the water out -period. Of course, I countered with proper detailing at all the joint conditions. The detailing does have a drip at each horizontal, but it shows punching the wallshield (their tighter woven tyvec material)and they just say you would have to put the panels under water for the capillary action to take water past the panels. Any thoughts except - NO DON’T DO IT? My last concern is that all of this is left to the individal installers hand and to the sub-contractor signing on to coating a substituted material and providing a warranty.