How to Install a Residential Wood Guardrail

Measure the distance between the posts that support the roof to determine the length of the guardrails. Cut 2-by-4 boards to fit this distance to be the bottom rails of the guardrail. For the top of the guardrail, use top handrailing, which are manufactured with a groove along the bottom edge that fit over top of the spindles.

Cut the spindles for the guardrail. Aesthetically, the railing looks best when the top edge is the same height as the bottom of the windows, but the height requirements of local building codes supersede this, so follow the building codes first and foremost.

Mark the location of the spindles onto the 2-by-4s for the bottom rails, and drill pilot holes at each point. Follow local building codes regarding the spacing of the spindles.

Install the spindles along the bottom railing by driving 3-inch deck screws through the pilot holes and into the ends of the spindles.

Lay the top handrail on the ground with the grooved side facing up, and insert the tops of the spindles into the groove. Align the side edges of the top and bottom rails, then drive nails through the spindles and into the handrail with a nail gun at a 45-degree angle.

Cover the guardrail with a coat of primer, and allow it to dry.

Paint the guard rail, and allow it to dry. Add a second coat of paint, and allow that coat to dry.

Measure the width of the top handrail, and make a small mark along the midpoint at each end. This acts as a guide when you're installing the guardrail so you can center it on the posts.

Place a wooden block onto the porch next to each post. The guardrail will rest on these blocks while you attach the guardrail to the posts.

Place the guardrail onto the blocks.

Measure the width of the post, and make a small mark at the midpoint just above the guardrail.

Move the guardrail so that the guide marks on the posts and guardrail are aligned, and attach the guardrail to the posts with finish-head screws. Drive the screws through the top and bottom rails and into the posts. When doing this, drive the screws deep enough that the heads of the screws go beneath the surface of the rails.

Install the other sections of guardrail using the same process.

Fill the holes with wood putty, and sand it down until it's flush with the wood. Paint over the wood putty.