Curious what the majority are using for receptacle boxes. Locally(Manitoba), I've found that Iberville (Thomas & Betts) make a steel box with wings allowing to screw to the nylon web supports on one side and Ipex makes the plastic box with the 'jaws' that lock the box in place. I guess my biggest concern is that with either of these, will the boxes not come loose over time with repeated plugging/unplugging. I can't imagine foam or a nylon web permanently holding the box in place. Is there an issue with code to attach the box directly to concrete with a concrete screw (assuming you can find a proper depth box). I know you're losing a little insulation value doing this, but would there be a possibility of condensation or code issue with that insulation being gone on the inside, where the box is located (-30 degC winters are the norm here). Any thoughts appreciated. Thanks, Greg

Boxes can be glued in place with low-e foam, or use a construction adhesive (eg, PL-400) to glue the back of the box to concrete, or concrete anchors through back of box to concrete. If the box is not the correct depth, you may need to shim behind the elec box.

Another option is using the Inexo ICF box. It is a little more expensive, but cuts down on install time and holds well. Not sure if I can post a link to the website but if this doesn't show, just google "Inexo ICF Box". It's made by Ipex.

http://www.ipexamerica.com/Content/Products/Product.aspx?ProductId=109&SubMarketId=17&MarketSegmentId=5

Greg, I'm on Ontario. I'm just finishing up my elec. rough-in. I used the Inexo boxes, I removed the foam back to the concrete and when I installed the box I just used "Great Stuff Pro" and sprayed behind the box so it filled the space between the box and concrete and holds the boxes in place, along with the "jaws" I mounted all boxes beside the plastic ties but didn't use screws.

http://www.icfelectrical.com/icf_electrical_box.asp

Where can one get this box? I looked around and the company contact info for the SW region is not valid.

Krom, thanks for the input, but unfortunately my walls are already poured. Stui, thanks for the pics on the Inexo boxes. I thought they were quite expensive, but when you start looking steel boxes for anything more than single gang, the price gap closes pretty quick. Thanks again, Greg.