Earthbound SlackJack: a seismic, snow and wind load holdown system for wood framed structures, Intact Structural Supply.

Posting Calculator Notes
  1. Calculations based on NDS 2018.
  2. Joist on Wall calculates member height = Wall Height minus given joist height and minus 4.5 inches for horizontal plates.
  3. Joist Hanging calculates member height = Wall Height minus 4.5 inches for horizontal plates. Also known as “balloon or platform” framing.
  4. Perpendicular to Grain Compression: DF = 625 psi, HF = 405 psi, SYP = 565 , SPF = 425.
  5. Refer to NDS 2018 Tables 4A, 4B and 5D for specific wood properties.
Stud/Plate
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Posting Grade
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No. 1   No. 2
Joist Condition
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Joist on Wall
Joist Hanging
Posting Options
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Bridge Posting
Include 3x4 Posting
Exclude 2x Bundles
First floor condition
Joist Height
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inches
Floor Height
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ft. in.
Load Duration Factor
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(CD)
Compression Load
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Input load in pounds
     
 Valid load range > 1 and < 88950
 Numeric values only!
Comments/Questions
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Posting Results
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