Deck Railing Repair

Add joist blocking to firm up that shaky railing

Stiffen a wobbly deck railing by adding blocks along the rim joist. It's a quick and easy way to firm up the railing.

By the DIY experts of The Family Handyman Magazine

Stiffen wobbly deck railings

Deck posts and railings screwed to a single rim joist feel wobbly because the rim joist flexes whenever you lean against the railing. Adding blocking will stiffen the rim joist and make the railing feel much more solid.

First, tighten any loose bolts and screws. If the post doesn't have bolts, add them—carriage bolts work best.

Cut pressure-treated 2-by blocking (the same width as the floor joists) to fit tightly between the rim joist and the next joist. Place the blocking directly behind the post and toe-screw it into both the rim joist and the neighboring joist. Fasten additional blocking every 4 ft. along the rim joist.

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Required Tools for this Project

Have the necessary tools for this DIY project lined up before you start—you’ll save time and frustration.

  • Circular saw
  • Drill/driver, cordless
  • Adjustable wrench

Required Materials for this Project

Avoid last-minute shopping trips by having all your materials ready ahead of time. Here's a list.

  • 2x blocking
  • 3-in. deck screws