How to Install a Composite Railing on a Porch or Deck

Video Transcript

Now, looks can sometimes be deceiving. Take this porch railing, for example. From a distance, it looks fine but on closer inspection, it's clear that it's seen better days. Flaking paint and rotted wood have rendered it not only unattractive, but also unsafe. The railing is too far gone for repair. The only option that makes sense is to replace it.

Demolition is fairly straightforward. The rails were toe-nailed into the post and house and are easily cut away, using a reciprocating saw.
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A pry-bar and claw hammer make short work of removing what remains. After a trip to the home improvement center to pick up the new fence, we unload it and get to work installing. The pre-assembled railing is made from a composite material by Barrette Outdoor Living.

We're going to begin by digging post holes for the stair railings, using first a shovel and then a clamshell post-hole digger. Next, we cut the composite post sleeve to length. Inside the sleeve, we place a pressure-treated 4 x 4, then plastic inserts at the bottom and top.

Then the post is set in place, plumbed and the hole is back-filled with gravel and soil. Now the posts are pre-drilled for the railing brackets. Then the brackets are clamped in position and secured in place with rust-resistant screws.
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This mounting plate with a convex back is designed specifically for attaching the upper ends of the stair railings to the round porch columns. The plate is mounted first, then railing bracket bases are installed, top and bottom. Plastic plugs conceal the screw holes.

Next, the composite rails are cut to length and plastic angle brackets are attached to the ends. The pre-assembled sections are set in place and lowered so that the angle brackets engage the bracket bases. Anchor pins are inserted and snapped into place.

Then the entire assembly is locked in position with rust-resistant screws. The process is repeated on the other side. Finally, adhesive is applied to the composite post caps and they're set in place. The posts on the porch deck have an inner steel column with a mounting flange at the bottom. Clearance holes are drilled through the deck, bolts are inserted — a metal support plate is slipped on underneath and the nuts are threaded on and then tightened with a socket.

Pilot holes are drilled through the remaining two holes, since they sit over the porch rim joist. Leg screws are inserted and tightened until secure. Next, a plastic insert is slipped over the steel column and pushed to the bottom.

The composite post sleeve is placed over that. Additional inserts are added at the top, making a snug fit between the steel column and sleeve. Then a trim ring is slipped over the post and lowered to the bottom. With the post in place, rail mounting cleats are attached, top and bottom.
Where the rails will connect to the columns, the convex column base plates are installed first. Then the rail mounting plates are fastened on top. The pre-built railing sections are cut to length, fitted with N-brackets, positioned over the mounting cleats and lowered into place so that the brackets and cleats engage each other.

Then a rust-resistant screw is installed to lock the assembly together. Finally, glue is applied to the remaining post caps and they're set in place. A composite railing system like this one is strong, durable, virtually maintenance-free and guaranteed against cracking, warping, mold and mildew. Now, how can you beat that?