How to Build Railing for a Deck

by HomeRepairExpert.com
Decks can be meeting places, party hot spots, play areas and eating spaces. For safety, however, it is best to have a railing to keep people from falling off. Railings don't need to be complicated, and usually only require a few hours to complete. They are best when constructed with the same lumber as the deck, and treated with the same stains and protective coatings.

  • Tape measure
  • Pencil
  • 2-by-4 boards
  • 6-inch lag bolts
  • Wrenches
  • Level
  • Construction square
  • Drill
  • 3-inch wood screws
  • Picket boards
Measure the perimeter of the deck to determine the number of railing boards you will need to complete the railing. Also measure the space you will need for the support posts by determining the finished height for the railing.

Connect 2-by-4 boards to the external deck frame with lag bolts. These should be at the height desired for the finished railing. Center the support posts every four feet. Use a level and construction square to keep things straight. For very long railings, or to make the railing sturdier, consider making them three-foot spans. For corners, use two pieces to create a 90-degree angle at the corner.

Attach 2-by-4 pieces around the outside perimeter of the railing with the 4-inch side against the posts. Connect them securely with at least two 3-inch wood screws placed vertically. Have the connections between two boards meet at the center of the support post so that each piece connects to half of the post.

Cut a 4-inch piece of scrap wood to use as a spacer between pickets. Measure the distance between each post and find the center point. Place the first picket board vertically at that center point, connected to the external frame with one screw and the inside of the railing board with another. Continue placing pickets, using the spacer to keep the gap consistent, until the span is completely filled. Move on to the next, and continue until all the pickets are in place.

Place a 2-by-4 horizontally across the top of the railing around the entire railing to form a shelf. Connect these pieces by laying them flush with the outer railing board and placing two wood screws each down through and into the board below.

Tips and Warnings

  • Be sure to stain and waterseal the railing the same as the rest of the deck to protect it completely.
  • Miter the joints at corners for a clean, professional look.
  • 2-by-6 lumber is an alternative to the common 2-by-4 construction.




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