most guys installing dryer/washer receptacles or even a standard 120v 15a recetacle in a basement first mount a wooden board to a cement wall... is that required by code, or is it legal to install receptacle directly to a concrete wall?
It's not the outlet that is in question, it is the wiring method: 334.12 Uses Not Permitted. (10) Types NM and NMS. Types NM and NMS cable shall not be used as follows: d. Where exposed or subject to excessive moisture or dampness
The cement wall *can* be considered to be a "damp" location and be easily tested by taping some plastic to the wall...after a few days moisture may appear on the inside of the plastic.
I don't know about you (or anyone else), but it's a whole lot easier to just slap up a half a 2x4 up on the wall and staple the wire to it than it is to "test" the wall and strap the NM to the cement.
~~ CELTIC ~~ ...-= NJ =-...
#99479 - 01/02/0604:42 PMRe: Dryer rec. in unfinished basement
Using wood is the cheapest way of doing for sure, but I prefer doing it in pipe too. It looks more professional and the NM is w/o a doubt protected from physical damage. I can consider that an important thing to do, especially any receptacle operating at 220 volts in an unfinished basement!
#99484 - 01/15/0609:28 PMRe: Dryer rec. in unfinished basement