How to Build a Balcony Handrail

Corner and Structural Posts

• 1

  Measure the side of the balcony from the bottom of the floor joist to the top of the deck. This is in preparation for installing posts at each corner of the balcony and along longer, uninterrupted spans of the balcony's edge. Building codes usually dictate the maximum distance between posts.

• 2

  Pick a post and choose one side, which will be referred to as Side A. Any side will do to start with, since all sides of the post should be 4 inches wide.

• 3

  Place the blade of the handsaw on the bottom end of the post and parallel to Side A, 1.5 inches in from Side A. Saw into the end of the post to make a cut that will be as long as the distance you measured from the bottom of the floor joist to the top of the deck. This cut should be parallel to Side A.

• 4

  Place the blade of the saw perpendicular to Side A and aligned with (over) the end of the long cut you just made. Make a 1.5-inch cut into the side of the post, perpendicular to the previous cut. Stop when the second cut meets the end of the first one. A piece of the post will fall off. The resulting L-shaped notch should be 1.5 inches deep and as long as your measurement of floor joist to deck top. Cut a similar notch in the bottom of each post.

• 5

  Place the blade of the handsaw at the top end of one post and position the blade parallel to Side A, 1.5 inches in from the edge. Saw into the end of the post to make a cut that is 3.5 inches long. This cut should be parallel to Side A.

• 6

  Place the blade of the saw perpendicular to Side A and aligned with the end of the long cut you just made. Make a 1.5-inch cut into the post, perpendicular to the long cut. Stop when the second cut meets the end of the first one. A piece of the post will fall off. The resulting L-shaped notch should be 1.5 inches deep and 3.5 inches long. Cut a similar notch in the top of each post on Side A.

• 7

  Stand each post over the side of the balcony in the position where you wish to attach the post, so that the edge of the balcony fits into the notch you cut in the bottom of each post. Side A of each post should face the balcony.

• 8

  Drill two pilot holes through the bottom of each post and into the balcony. Use a socket wrench to install a carriage bolt into each hole to hold the post to the balcony.

2-by-4 Rails

• 9

  Install a continuous series of 2-by-4 pieces of lumber at the top of the corner and structural posts. Set the 2-by-4s end to end so that they connect each post around the perimeter of the balcony. The 2-by-4s should be set on their sides into the notches at the top of the posts. (They should fit because the actual measurement of a standard 2-by-4 is 1.5 inches by 3.5 inches.)

• 10

  Cut the ends of the 2-by-4s at the corners of the balcony with a miter saw so they form a 90-degree angle.

• 11

  Drill two 2-inch wood screws into each corner post to hold the 2-by-4s in place.

Balusters

• 12

  Install balusters between the posts. Position each baluster on the outer side of the handrail so the top of the baluster is flush with the top of the 2-by-4 railing, and the bottom of the baluster is flush with the bottom edge of the balcony.

• 13

  Screw each baluster into place with two 1.5-inch wood screws -- one on the top of the baluster and one on the bottom.

• 14

  Place a plastic spacer between the first baluster and the next to create an equal distance between balusters. Move the spacer each time you install a new baluster.

Handrail

• 15

  Install a handrail over the top of the posts and 2-by-4 inch railing. Use 5-quarter decking for this. Center the 5-quarter deck boards over the top of the corner posts and screw them down with 1.5-inch wood screws.

• 16

  Lay the 5-quarter deck boards end to end so they appear to be one continuous board.

• 17

  Cut the 5-quarter-inch boards with a miter saw where they meet at the corners so they form 90-degree angles.