Layout and build the porch (or deck rail) section in the workshop. The porch or deck rail can be built outside, but I was working at night so it was more convenient to build the rail in the workshop.
This project is continued from How to Build a 2×6 Porch Rail – Part 1.
Layout the Porch Rail Pickets
After priming and painting the western red cedar boards for the porch rail, I sawed the 8 foot boards 1″ longer than needed to allow for a margin of error during final fitting. Next I laid the 2″ x 2″ x 36″ pickets on 5″ centers to ensure everything would turn out the way I expected. A 2×4 block is perfect for spacing the pickets on 5″ centers with a 3-1/2″ gap between pickets to satisfy the building code. Recall that a 4″ sphere cannot pass between the pickets per the building code.
Note the vertical block at the left side to set the gap for the horizontal post support as indicated in the scale drawing (see How to Build a 2×6 Porch Rail – Part 1).
2×6 Porch / Deck Rail Construction
I stacked the boards upside down on the sawhorses to illustrate how the top rail and pickets will be assembled. Nothing is nailed or screwed together here:
This photo shows how the porch rails are assembled with exterior screws:
- The subrail is fastened to the edge of side rail with a Grip-Rite 3″ stainless steel screw.
- The 2×6 top rail is fastened to the 2×4 subrail with a 2-1/2″ DECK MATE EVERCOTE exterior screw.
The screw length is important so as not to over-penetrate the boards. Corrosion resistant or stainless steel screws are a must for exterior applications and required per the building code.
Why use screws instead of nails? Because screws won’t back out over time as the boards expand and shrink with seasonal temperature changes.
Porch Subrail and Side Rail Assembly
I could have built the deck rail in place on the front porch, but I’m working at night in the workshop to make progress. The porch rail is a little over 6 feet long, so carrying it outside to the front porch won’t be a problem.
The subrail is laid face down on the edge of the 2×4 subrail and fastened with 3″ stainless steel screws on 8″ centers starting about 2″ inches from the end of the board. Take care to drive the 3″ screw straight down so you don’t punch through the face of the side rail. The best way to align the subrail over the side rail is to double it with another 2×4 as shown.
Here’s the 2×4 subrail after fastening the 2×4 side rail with screws on 8″ centers. Note the unpainted 2×4 board used as support while I was driving the screws.
The screws are sealed with a dab of white GE Silicone II Paintable Silicone caulk – I like this brand because it’s “30 minute paint ready” and silicone doesn’t shrink or crack and stays permanently flexible. The purpose of the caulk is to seal the wood around the screw.
View of the assembled and caulked subrail and side rail (left side of photo). The 2×6 top porch rail on the right will be attached next.
Install the 2×6 Porch Top Rail
The 2×6 top rail will be fastened to the 2×4 subrail with 2-1/2″ DECK MATE EVERCOTE exterior wood screws:
I set the screws on 8″ centers starting 6″ from the end of the board as shown, placing two screws side-by-side at both ends and the center to eliminate any possible wobble. The screws are set flush with the face of the 2×6 board so there’s no bump.
The screw heads given a dab of caulk and smoothed with 2″ putty knife to make the screws almost invisible. After the caulk dries, the top rail is given another coat of Sherwin-Williams Duration® paint. Always paint exterior caulk because it’s slightly tacky and will collect dirt/dust if left unpainted.
Here’s the assembled and painted 2×6 porch rail and stack of 2×2 pickets:
Illustration of how the 2×2 picket fits into the 2×6 porch rail:
This project is continued in How to Build a 2×6 Porch Rail – Part 3.