1-1/4" Flex conduit fill
1-1/4" Flexible metal conduit (FMC, Greenfield) has an inside area of 1.277 sq in (1.275 in across). Three or more wires may take 40 % of it: 0.5108 sq in.
- One wire, 53 %
- 0.6768 sq in
- Two wires, 31 %
- 0.3959 sq in
- Three or more, 40 %
- 0.5108 sq in
- Nipple, 60 %
- 0.7662 sq in
- Support
- Every 4.5 ft, 12 in from boxes
How many wires fit in 1-1/4" Flex
All wires the same size and type, by Annex C's method. For a mix of sizes, open the calculator.
| Wire size | THHN/THWN-2 | XHHW-2 | THW/THW-2 |
|---|---|---|---|
| 14 AWG | 52 | 36 | 36 |
| 12 AWG | 38 | 28 | 28 |
| 10 AWG | 24 | 21 | 21 |
| 8 AWG | 14 | 11 | 11 |
| 6 AWG | 10 | 8 | 7 |
| 4 AWG | 6 | 6 | 5 |
| 3 AWG | 5 | 5 | 4 |
| 2 AWG | 4 | 4 | 4 |
| 1 AWG | 3 | 3 | 2 |
| 1/0 AWG | 2 | 2 | 1 |
| 2/0 AWG | 1 | 1 | 1 |
| 3/0 AWG | 1 | 1 | 1 |
| 4/0 AWG | 1 | 1 | 1 |
| 250 kcmil | 1 | 1 | 1 |
| 300 kcmil | 1 | 1 | 1 |
| 350 kcmil | 1 | 1 | 1 |
| 400 kcmil | 1 | 1 | 1 |
Other 1-1/4" conduit
| Conduit | Inside area | #14 | #12 | #10 | #8 | #6 |
|---|---|---|---|---|---|---|
| Flexible metal conduit (FMC, Greenfield) | 1.277 | 52 | 38 | 24 | 14 | 10 |
| Electrical metallic tubing | 1.496 | 61 | 45 | 28 | 16 | 12 |
| Intermediate metal conduit | 1.647 | 68 | 49 | 31 | 18 | 13 |
| Rigid metal conduit (RMC, GRC) | 1.526 | 63 | 46 | 29 | 16 | 12 |
| Rigid PVC conduit, Schedule 40 | 1.453 | 60 | 43 | 27 | 16 | 11 |
| Rigid PVC conduit, Schedule 80 | 1.237 | 51 | 37 | 23 | 13 | 9 |
| Liquidtight flexible metal conduit (LFMC) | 1.528 | 63 | 46 | 29 | 16 | 12 |
| Electrical nonmetallic tubing (smurf tube) | 1.453 | 60 | 43 | 27 | 16 | 11 |
About Flex
Flex is supported every 4-1/2 ft and within 12 in of each box (348.30). Short whips to equipment have their own exceptions. See strap spacing and the fill rules.