- 1). Lay the predrilled bottom channel rail on a smooth surface to prevent paint damage. Turn the bottom channel rail on its side. Position a picket to align the predrilled holes together with the predrilled holes on the bottom rail. Insert two 1¼-inch bolts through the holes and hand turn them halfway into the holes. Use the drill and bit to tighten the bolts down flush to the rail. Do not overtighten the bolts. Continue until all of the pickets are secured to the bottom channel rail.
- 2). Lay the predrilled top snap rail on top of the opposite end of the pickets. Position the snap rail to align the predrilled holes to the holes in the pickets. Insert one 1¼-inch bolt through the first and the last picket and hand turn them halfway into the holes. Insert one 1¼-inch bolt through aligned holes of a center picket. Hand turn the bolt halfway into the holes. Wait to tighten the bolts completely until every picket has been placed correctly. Turn the handrail assembly upright. Insert one 1¼-inch bolt through each of the aligned holes and secure the remaining pickets to the rail with the drill.
- 3). Position the top cap over the top snap rail. Adjust the top cap until the end is flush with the end of the top snap rail. Press the top cap together with the top snap on one end to pop it into place. Press and snap along the top cap until it is secured to the end.
- 4). Slide a post mounting bracket over each of the four ends of railing. Position the previously assembled handrail section between the two existing posts. Cut equal lengths from each end of the railing with the hacksaw if the assembly is too wide to fit between the posts. Example: If the railing is 4 inches too wide, cut 2 inches off each end. Do not cut 4 inches off one end.
- 5). Insert one 1¼-inch bolt through each of the two holes of the mounting bracket on the bottom of one end of the railing. Secure the bottom mount of the channel rail to the post using the drill.
- 6). Adjust and center the handrail vertically on the post. When the handrail is centered, insert two 1¼-inch bolts through each of the two holes in the mounting bracket. Secure the top to the post using the drill.
- 7). Lay a level on top of the railing. Adjust the height of the railing until it is level. Slide a wood block under the bottom of the railing for support. Repeat steps six and seven to secure the railing on the opposite end to the post.
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