Joist Spacing and Blocking 101

Joist Spacing and Blocking
Quick Reference Guide
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To extend the life of your decking substructure, apply joist tape. This will help prevent water
penetration and will protect the joist lumber from rot.
Select a tape width that allows for overhang
on each side. Use 1.625”
or 2.5” tape for single joists, and 3.25” tape
for double beams for general flashing, use 4”
and 12” tape.
• It’s best to apply this tape to
clean, dry lumber
Apply the tape to the top of a joist or beam
using firm pressure (preferably with a hand
roller) to ensure adequate adhesion.
• Try to avoid wrinkles or air
bubbles during application
Application temperatures from 20°F to 170°F
Service temperatures from -70°F to 200°F
Apply TimberTech Pro
TM
Tac Joist Tape
STEP FOUR