Recommended Box Configurations
We recommend plastic, metal, or fiberglass electrical boxes. A good resource for finding the right size box is Allied Moulded Products. You can use their website to find a local distributor for nearly all of their products.
- 2½” deep box – we recommend Allied Moulded Products’ 9331 Series
- 1½” deep two gang box with a 1″ mud ring
- 1½” deep two gang box with a ½” mud ring mounted on ½” plywood or insulation board
Recommended Types of Wiring
InSoFast panels are designed for use with standard Romex® (NM sheathed wire), MC Flex, AC Flex, or rigid metal conduit.
InSoFast wiring chases are located 1¼” below the surface of the panel (National Electric Code – NEC Article 330-4d and 300-41a) and are designed to keep the wiring safely within the panel without the use of protective metal plates. The chases are spaced 16″ o.c. vertically and 24″ o.c. horizontally. This offers the same protection as a wire running through the center of a 2×4 wall.
Making Cut-outs for New Outlet Boxes
Just press the outlet box against the foam of the InSoFast panel to create a mark. Cut out the foam approximately ¾” larger on all sides than the impression. While a tight-fitting electrical box would look nice, it is better to have extra room to seal around the outlet box with expanding foam.
Cut out the foam with a snap-off blade knife. Continue to cut out to the nearest horizontal or vertical chase. The vertical chases are centered directly between the InSoFast studs and are indicated by a line on the front side of the panel. The horizontal chases are located at the top of each panel.
To make things easier and give you extra room to work with the wiring, cut the opening up to the horizontal chase way.
Making Cut-outs for Existing Boxes
Press the InSoFast panel in place over the existing outlet to indent the back of the panel. Cut about ½” to 1″ larger than the indentation. If there is conduit, repeat the process to accommodate the conduit. If you have problems seeing the indentation for the conduit, you can mist the conduit with spray paint. This will transfer to the back of the InSoFast panel highlighting the area to be removed. Cut out with router or utility knife. Glue the panel into place and fill in gap around the electrical box with the expanding foam. Box extenders can be used with existing electrical boxes.
Installing Outlet Boxes
Secure electrical boxes directly to the concrete wall with adhesive or a mechanical fastener. Fill the extra space above the box with expanding foam. The foam seals the electrical box and serves as the code required attachment of the electrical wiring within 8″ of the electrical box.
Rigid Metal Conduit
If you are planning on using rigid metal conduit, install the ½” metal conduit at the same height all the way around the project. Use box offsets so that the conduit is setting tight against the concrete wall.
You can cut the InSoFast panels as needed to align the horizontal chase way with the metal conduit. The cut off portion can be used at the top of the wall. This method utilizes the tongue and grooves to their best potential.
Romex® type wiring is simple to install. Individual runs can be pushed or slid through the horizontal or vertical chase ways up to 12′ from box to box or up into the floor system.
If you have any difficulties sliding the wire through the chase way, bend over the end of the Romex® wiring.
The use of a fish tape is generally not required unless pulling multiple wires at one time. If you wish to eliminate the fish tape, slide one wire through and then tape the multiple wires on.
Metal flex conduit, MC Flex, or AC Flex installs in the same manner as Romex wiring.