our inspector requires panels mounted in basements to be seperated from the concreate wall by plywood. Does anyone know in the code where it requires this? Also, If the wall is studed and the panels are mounted to the studs with the concrete behind them, would this still require the plywood?
I would ask the AHJ wich article in the NEC he is referring to if he's requiring you to do this. I did some looking around at article 408, and from there one of the articles referred me to 312.2 (A). As long as the panel is elevated 1/4" off the concrete wall I don't believe there is a violation. However, unless a panel is mounted between two studs I ALWAYS use a sheet a plywood as a barrier from the concrete wall. Think corrosion.
The sheet metal protects the plywood (vapor barrier) and the plywood protects the panel? I would think VisQueen would do the same thing. If the basement walls are damp you can make the 312.2 (1/4") rule work.
I forgot that basements are non-existant in some areas of the country. I just got back from the Carolina's and they didn't have any down there either. I've become so accustomed to them that I could not imagine not having one. Where would I store all my crap? LOL.
By the way, isn't all concrete considered to be a damp location? And why don't inspectors enforce 4x4 metal boxes on concrete walls be mounted on some sort of wood? If we do it for panels, we should also do it for any metal electrical box.