Junction box in a horizontal application

Step 5:

To install the electrical box, check to see if the cover plate is for horizontal or vertical placement. 

Corner pilot holes will determine size of rectangle to cut

Step 6:

You need to drill corner pilot holes.

From the interior, cut hole for box

Step 7:

Cut through the sheathing with a reciprocating saw or keyhole saw.

Keep hole size close to box to reduce later filling to reduce air infiltration

Step 8:

Make the opening large enough to allow the box to come through.

Mount junction box securely

Step 9:

The box will need to be mounted securely, preferably using screws. The box should protrude and be flush with the exterior sheathing.  

Run cable through sill plate to junction box

Step 10:

Bring power to the box by running cable from the outlet back to the breaker box. Click here if you need help understanding circuit diagrams. While 15 Amp service might pass code, you are probably better off going with 12 gage wire and using 20 Amp GFCI.  It may cost a few dollars more, but will allow you to more safely use power tools from the outlet.

Two wire BX cable ready for junction box

Step 11:

You'll need to drill through sill plates using 5/8" speed bit drill. In this how-to, we have chosen to use armored or BX rather than Romex cable and metal boxes for a good secure weathertight fit. If you use BX cable, don't forget the anti-short or insulated bushing. If you have part of the cable exposed to sunlight (such as below the siding along the foundation), make sure that you use UF/sunlight rated cable. You may also need to use conduit. Check with your building codes as standard two wire may not be enough and three wire may be needed.  

Attach hot lead (black)

Step 12:

To attach outlet, it is a good idea to coat the wires to an anti-oxiding coating.  This will help years down the road from excessive oxidation forming and causing a break in the connection.

Attached neutral wire (white)

Step 13:

You want to attach the hot lead and neutral

Attach ground wire (green)

Step 14:

Also, the ground wire. Place in box and attached cover plate.  To tie into breaker box, we recommend you seek a licensed electrician. 

1 - 2

Printer friendly page

E-mail this page to a friend

Please note:  We consider all of the information on this site to be reliable.   We strive to provide the best home improvement and repair content possible, but we assume no liability for the information contained herein. [Full Disclaimer]  
All information contained is © Copyright 2000 - InsideSpaces.com, Inc.           Click here to read our privacy statement.