Electric Wiring Help

I am wiring the basement to my cabin and I have need of some advice. If anyone can help it is greatly appreciated.

1. I have insulated concrete forms for the walls, with 2 inches of styrofoam on the inside of the walls. Is there a best method of running the power down these walls? Do I need to have conduit? Can I just run NM-B Romex?

2. What determines if an area is a “wet area” that requires metal boxes? Just because it’s in the basement below ground does that mean I need metal boxes and conduit? Does the bathroom need metal boxes for the GFI? How about the light switch?

3. Finally, is there a good resource available to do-it-yourselfers like me that has these answers? I called my local state electric inspector with the same questions but got no response to my voicemail?

Thanks.
Dave

I am not an electrician but have done some wiring and this is my understanding.

1. If you stud up the wall you can use romex and staple to the studs. If not stud walls you would need to use conduit.
2. If working with stud walls you would not need metal boxes and conduit.
3. There are some self help books available at stores like menards, home depot etc.

Good luck wiring is pretty easy to do.

You shouldn’t need metal boxes for any of those situations for the foam we always would use a router and plow trench for wire and boxes then stuff something on top of wire to keep in back of channel. The source for info is a good electrician or an inspector that will get back to you.

I am not an electrician, but did a quick web search as I was curious about how to solve your problem and came up with the following tips.

Use an electric chain saw to make grooves to route and retain the wire. Making a periodic waviness to the cut allows the wire to be retained.

Alternately, foam can be used to secure and retain the wire.

Some folks recommend Romax to avoid having to cut straight lines and place conduit into grooves.

No clear answer on the plastic vs metal box in my search. I do not see why this basement would be any different than other basements though where plastic is allowed.

One person suggested using the plastic boxes with tabs allowing one to secure the flat tab to whatever the plastic strap for attaching the drywall.

Thanks for the input. Does anyone know for sure if using foam to secure the wire in the styrofoam walls is acceptable, equivalent to using wire staples to secure the wire?

I don’t have an answer on the foam. Looked a bit more using a search on basement, electrical codes and came up with a lot of documents for Mn cities regarding remodeling of basements. None of which addressed your question. However, more typically, the basement would have the pink foam glued to the inside of the basement walls and taped seams, then studded out and wired same as upstairs areas. The web site I include has good pictures and lots of information. Having looked further at this, I realize that cutting the foam is going to be breaking your water barrier, so am thinking that this would not be good from the viewpoint of potential mold growth. Anyone finishing a basement is going to want to preserve any water barrier to keep moisture out of the walls.

Lakeville MN basement regulations