How to Build an Outdoor Wooden Couch

Lay two of your 4-foot posts parallel on the ground. Lay two of your 8-foot posts between smaller posts. Turn the longer posts perpendicular to the smaller ones. Line one long post up with the end of the small posts. Move the other long post so that it lays 28 inches from the free end of each short post. Drive two lag bolts through the side of the short post and into the end of the long post at each juncture to complete the back of your couch.

Lay two of your 36-inch posts on the ground with an 8-foot post perpendicular between the two. Move the longer board so that it runs between a point 8 inches from one end of the smaller posts to form an "H." Connect the assembly with two of your 12-inch lag screws through each juncture. This is the front frame of your couch.

Stand both assemblies. Arrange the assemblies parallel to each other with a 23-inch gap in between the two. Place an assistant at each assembly to hold it upright. Lay a 30-inch board on top of the 28-inch tall cross beams to connect the two assemblies. Place one board at each end of the cross beams. Connect the board to each frame by driving three of your 16d nails at each juncture with your framing hammer.

Lay a 30-inch board on top of one of the corner posts of the front part of the frame. Adjust the board so that one end of it rests flat against the adjacent corner post on the back frame. Drive two lag screws through the board to attach it to the front post. Toe nail three of your 16d nails through the other end of the board to secure it to the rear post. Repeat the process with your remaining 30-inch boards to complete the arm rests.

Lay deck boards across the two boards on either side of the seat section. Attach each deck board with two deck screws on each end. Drive the screws with the Phillips bit on your drill. Remember to set the drill to a lower speed to prevent stripping the screws. Cover the seat and back of the couch with deck boards. Leave an 1/8-inch gap between each pair of boards.