Rolling Offsets (run)

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Equation / Last modified by KurtHeckman on 2019/04/05 17:05
KurtHeckman.Rolling Offsets (run)

The Rolling Offset calculator computes the length of the run (R) or travel (T) based on the vertical (U) and horizontal (S) offsets and the fitting angles (fA) of the elbow fittings.   plumbing1.png             Rolling Offset  of Pipes or Conduit 

INSTRUCTIONS: Choose units and enter the following:

  • (U) - Vertical offset
  • (S) - Horizontal offset
  • (fA) - This is the elbow Fitting Angle.  (e.g.  22.5°, 30°, 45o, 60o, 90o)
  • (oC) - Choose run (R) or travel (T).

Rolling Offset: The calculator returns the run (R) or travel (T) in inches.   However, this can be automatically converted to other length units (e.g. centimeters or feet) via the pull-down menu.  

Related Items:

  • For the travel (T) in the diagram choose Travel (T) or CLICK HERE .
  • CLICK HERE to see YouTube Video Instructions for this calculator.


 When running pipes or conduits, it is common to have to change the run of the line of pipes by using two equal angled elbow fittings (see diagram).  The length of the run (R) and travel (T) created with the elbows and the length of pipe between them, can be calculated if one knows the vertical and horizontal offsets and the angle of the fitting.  

The Math

In the diagram above, the relationship between the travel length and the offsets is as follows:

                                             ` x = sqrt( U^2 + S^2)`

                                              ` T = x / cos (90 - fA)`

                                               `R = sqrt(T^2 - x^2)`

Note: vCalc allows for multiple units for both length (SI and English) and for angles (degrees and radians).  The result will be in inches.  However, this can automatically be converted to other length units (e.g. centimeters) with the pull-down menu.

General Plumbing Calculators


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