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Stesso

Squaring and Blocking Joists

1:29
2:58
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At 1:29 in

Learn why decks fail and how to install a deck 💪 #decks #learn #carpentry #flashing

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What happens here

To ensure the deck frame is square, use the 3-4-5 rule for perpendicular joists. This involves measuring 3 units along one side, 4 units along the adjacent side, and then verifying the diagonal measurement is 5 units. The presenter also shows how to copy the ledger layout onto the beam. Crucially, blocking should be added between joists. Without blocking, joists can twist and deflect. Adding blocking provides significant rigidity and prevents such movement, as demonstrated with a large wooden cutout.

Goal: Ensure the deck frame is square and rigid by adding blocking.

Tools and materials

  • Blocking — Adding rigidity between joists
  • Large Wood Cutout — Demonstrating joist twisting and the effect of blocking
  • Tape Measure — Measuring for the 3-4-5 rule and layout
  • Wood Pieces — Demonstrating the 3-4-5 squaring method

What they say

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short nails don't go into the ledger. If you use the right nail, it attaches the joist to the ledger. If you install the right size nail, this is much stronger. Square up your perpendicular joist and doing a three, four, and a diagonal five. Copy your ledger layout onto your beam. If you have no blocking, it can cause twisting and deflection. When you add blocking, now if we try to twist, the other joist add rigidity. Measure out your deck length and chalk line your overhang. Snap, then mark, and cut your tails. Nail your rim [snorts] joist.

Auto-generated from the video audio.