How to Build a Deck Railing Inside the Rim Joist
- 1). Expose the rim joist at the length of deck where the railing is to be installed.
- 2). Measure the length of the railing and divide equally for centerline placement of the vertical posts. Mark the layout of the posts on the rim joist and mark a square pencil line down both vertical faces of the rim joist(s). This will be the centerline of each post and centerlines for drilling bolt holes.
- 3). Mark the posts to be cross-cut at 4½ inches from the top end of the post, to a cut depth of 1½ inches.
- 4). Mark a pencil line from bottom of the previous cut to the bottom of post and cut to meet the end of the crosscut. Complete the final removal with a handsaw. This notch will sit on top of the rim joist at the centerline layout.
- 5). Mark the center line of the post and two ½-inch holes 5 inches apart, equidistant from the ends of the notch. Do this on the face of the post opposite the notch.
- 6). Drill ½-inch holes on the center marks through to the notch.
- 7). Set the post on the rim joist with the pencil-marked centerline visible in the center of the drilled holes and mark the hole centers.
- 8). Drill ½-inch holes in the rim joist(s) at the center marks.
- 9). With post in position, Hand-tighten the ½-inch bolts, nuts and washers through the drilled holes to verify the fit. Remove and use the first cut post as a template for the remaining posts to be cut. Follow step 1 through 8 for each post.
- 10
Install the posts on the centerline layout and install the bolts, ensuring that the posts are plumb and bolts are securely tightened. - 11
Install decking over the rim joists. Notch decking as needed at the post locations. - 12
Cut two 2-by-4 boards to fit horizontally between each post. Position one 2 inches vertically above the finished decking surface and 2 inches in from the outside face of the posts. Position the other flush with the top of posts and 2 inches in from the outside face of the posts. Secure both in place with 16d finish nails top and bottom into posts. Repeat between all posts, except at steps or access. - 13
Attach 2-by-2 pickets vertically to the top and bottom horizontal 2-by-4 supports at a maximum spacing of 4 inches apart. Secure the top and bottom with 10d finish nails through picket into support. Position pickets flush with the top of the posts and top support. - 14
Install 2-by-6 board as a cap to the top of the posts, centered on the posts. The top cap can be nailed to the top of the posts and midspan into 2-by-4 picket supports as needed.
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