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Thrust in a Raised Rafter Tie

This Raised Tie Rafter Thrust Calculator is for use with a roof system with thrust being restrained by ties raised above the plates.
Building code limits the tie to the lower third of the distance between the plate and ridge
Consult IRC Table R802.5.1 for rafter span adjustment factors for rafter sizing with raised ties
L= Rafter Span
W= Load on rafter (L x rafter spacing x roof design load)
H= Height of ridge above plate
h= distance between tie and ridge
T= Tie force (W/2 x H/h x run/rise)

Rafter Span, 1/2 Bldg Width (inches)
Load on Rafter (pounds)
Height of Ridge above Plate (inches)
Distance from Tie to Ridge (inches)
Pitch of Rafter (e.g. 6/12)
Thrust