calcs.homes
calcs.homes
Enter the depth of the obstruction you need to clear and your bend angle to find the distance between bend marks and total shrinkage to add to your measurement.
Add shrinkage to your total conduit run length to land your last fitting in the right spot.
Each bend angle has a standard multiplier (distance between bend marks = offset depth × multiplier) and a shrink constant (how much shorter the conduit gets per inch of offset). These are trade-standard ratios — they apply the same way whether you're measuring in inches or centimeters, since both figures are proportional to the offset itself, not tied to a specific unit.
30° is the most common choice for a standard offset — it balances a manageable bend distance against a moderate multiplier. Shallower angles (10°, 22.5°) need less shrinkage but a longer run between bends.
Because the conduit now travels at an angle instead of straight, the straight-line distance it covers is shorter than the conduit's actual length — you have to add that difference (the shrinkage) back into your overall measurement.