EMT Conduit Offsets: Multipliers, Shrink & Saddle Bends
Sam needs a 6" offset to clear an HVAC duct, using two 30° bends. Wrong shrink and the conduit hits the duct or won't reach the box.
- Hand bender (1/2" EMT)
- Sharpie
- Tape
- Cosecant table
- 1
Pick the bend angle
30° is the workhorse. Multiplier = csc(30°) = 2.0.
- 2
Compute distance between bends
Offset × multiplier. 6" × 2 = 12" between marks.
- 3
Account for shrink
30° shrink = 1/4" per inch of offset. 6 × 1/4 = 1 1/2" — measure that much further from the box.
- 4
Bend, slide, sight
Align both arrows the same direction. Sight down the run — should look like a perfect parallelogram.
Your 1/2" EMT run hits a junction box that's 6" higher than the conduit. Pick a bend angle, compute the distance between bend marks, then add the shrink to the cut length so the conduit lands exactly in the box. The math comes from the right triangle — multiplier = 1/sin(θ), shrink ≈ cot(θ/2) − cot(θ), tabulated for speed.
Tap Show next step to reveal the math one piece at a time.
6″ offset with 30° bends
Given: Rise = 6″, bend angle = 30°
- 1
Look up multiplier
30° → ×2.0
Same 6″ offset at 45°
Given: Rise = 6″, bend angle = 45°
- 1
Multiplier for 45°
1 ÷ sin 45° = 1.414