5" Rigid conduit fill
5" Rigid metal conduit (RMC, GRC) has an inside area of 20.212 sq in (5.073 in across). Three or more wires may take 40 % of it: 8.0848 sq in.
- One wire, 53 %
- 10.7124 sq in
- Two wires, 31 %
- 6.2657 sq in
- Three or more, 40 %
- 8.0848 sq in
- Nipple, 60 %
- 12.1272 sq in
- Support
- Every 10 ft, 3 ft from boxes
- Sold in
- 10 ft sticks
How many wires fit in 5" Rigid
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 | 833 | 581 | 581 |
| 12 AWG | 608 | 446 | 446 |
| 10 AWG | 383 | 332 | 332 |
| 8 AWG | 221 | 185 | 185 |
| 6 AWG | 159 | 137 | 111 |
| 4 AWG | 98 | 99 | 83 |
| 3 AWG | 83 | 84 | 71 |
| 2 AWG | 70 | 70 | 60 |
| 1 AWG | 51 | 52 | 42 |
| 1/0 AWG | 43 | 44 | 36 |
| 2/0 AWG | 36 | 37 | 31 |
| 3/0 AWG | 30 | 30 | 26 |
| 4/0 AWG | 25 | 25 | 21 |
| 250 kcmil | 20 | 20 | 17 |
| 300 kcmil | 17 | 18 | 15 |
| 350 kcmil | 15 | 15 | 13 |
| 400 kcmil | 13 | 14 | 12 |
| 500 kcmil | 11 | 11 | 10 |
| 600 kcmil | 9 | 9 | 8 |
| 700 kcmil | 8 | 8 | 7 |
| 750 kcmil | 7 | 7 | 7 |
| 800 kcmil | 7 | 7 | 6 |
| 900 kcmil | 6 | 6 | 6 |
| 1000 kcmil | 6 | 6 | 5 |
Other 5" conduit
| Conduit | Inside area | #14 | #12 | #10 | #8 | #6 |
|---|---|---|---|---|---|---|
| Rigid metal conduit (RMC, GRC) | 20.212 | 833 | 608 | 383 | 221 | 159 |
| Rigid PVC conduit, Schedule 40 | 19.761 | 815 | 594 | 374 | 216 | 156 |
| Rigid PVC conduit, Schedule 80 | 17.855 | 736 | 537 | 338 | 195 | 141 |
About Rigid
Rigid (galvanized rigid conduit, GRC) has the thickest wall and the least room inside of the steel types. Support follows 344.30: within 3 ft of each box, then every 10 ft, or longer on straight runs with threaded couplings (Table 344.30(B)(2)). See strap spacing and the fill rules.