How to Build an Outdoor Cat Cage

Buy the lumber for a 16-by-16-by-8 foot cage.

Take advantage of the sizes available at the lumber store to make whatever size cage you prefer or have space for. The 16-foot lengths will form the top and base frames and the 8-foot length will form the vertical supports.

Lay your base frame out on a flat surface.

Lay two sections of 16-foot lumber on the ground, parallel to each other and spaced about 16 feet apart. These will form the front and back of your frame. Lay the end-pieces on either side of your front and back, butting them against the ends of the front and back to form a square (technically not a square since it's about 7 inches wider than it is long).

Lay your flat nailer plates on top of the four corners of the square frame.

Center them over the joins between the front and side pieces. Drive the appropriate number of one-inch nails through the nailer plates. You can do this with a framing gun if you've got a good eye for it, but the safer option is to drive the nails in by hand.

Repeat the procedure with four more nailer plates on the sides of the frame. At this point the frame should be fairly secure. To ensure the frame's strength, turn the frame over and install nailer plates on the bottom (now the top). Lay a level on top of your frame and slide a few thin wooden shims underneath until the framework is completely level.

Raise one of the eight-foot vertical sections and push it into an inside corner of your base frame.

Slide a shim underneath until its base is flush with the bottom of the frame. Place the level on it and have an assistant keep it vertical while you drive a couple of framing nails into it on a diagonal (toe-nailing) to hold it in place. Repeat three more times until all of your vertical supports are up.

Cut eight six inch sections of 2-by-4.

Climb a ladder and hold a scrap piece of 2-by-4 up to the top of your vertical posts; hold it up so that it's flush with the top of the post and mark a line under it. This spacer trick will help to save you some measuring. Repeat on the eight outer sides of your four vertical posts.

Place one of your six-inch sections of 2-by-4 on a vertical post, aligning it so its top edge lines up with your reference line.

Nail it in place. Repeat seven more times on the other uprights. These pieces will help to hold your upper frame in place while you build and will give it some additional support after it's erected.

Lift one of the 16-foot sections up and set it on the 2-by-4 braces, then toe-nail it in place with the framing gun or by hand.

Have your assistants continuously check your vertical supports with the level while you're nailing. Repeat for the other three sides. Install your 90 degree nailer plates on the inside, and two flat nailer plates per corner (on the sides and tops of the frame joints. At this point, you'll have a sturdy wooden frame measuring roughly 16 feet long, 16 feet wide and eight feet tall.

Carry the frame to your house.

Frame a doorway or window and butt it up against the house. Do not, however, attach the frame to hour house in any way. Attaching the frame to the house changes it from a movable, free-standing structure into a structural addition. Such additions require expensive permits.

Wrap chain-link fence around the entire outer perimeter of your vertical posts, pulling it taut and holding it in place with staples.

Align the bottom section with the top of the bottom frame, and the upper section with the bottom of the top frame. If you used four-foot chain-link fence, the sections will overlap in the middle by about seven inches. Tire them together by weaving bailing wire between the links and wrapping around each link as you pass. Do the same with the top to fully enclose the cage.

Nail some 2-by-2 lumber to the top side of the bottom framework. The idea is to push the lumber up against the chain link, sandwiching the fence between the 2-by-2 and the vertical supports. Go inside the cage and staple the bottom edge of the chain-link fence to the insides of the 2-by-2 flanges. Repeat with by installing another 2-by-2 flange on the under-side of the top frame. At this point, the chain link is serving as a structural reinforcing member, and your critter enclosure is complete.