Calculate overall duct bank envelope dimensions, concrete encasement volume, and a minimum burial depth reference from conduit layout — for underground duct bank design and quantity takeoff.
// INPUTS
// Results update automatically as you type
// CONDUIT LAYOUT
inches (NEC) — 2" trade size EMT ≈ 2.375"
inches (NEC) — 3" typical minimum
// ENVELOPE & BURIAL
inches (NEC) — 3" typical minimum
Number of Conduits—
Conduit Group Width—in
Conduit Group Height—in
Overall Envelope (W × H)—
Concrete Volume—ft³ per linear ft
Minimum Burial Depth (reference)—in
Disclaimer: Burial depth shown is a general reference only. NEC Table 300.5 and IEC 60364-5-52 set minimum cover requirements that vary by voltage class, circuit type, and location (under buildings, driveways, roadways) in more detail than this tool models — always verify the exact minimum for your specific circuit type and location against the applicable table directly before finalizing trench depth.
Please check inputs — all values must be positive.
// RELATED TOOL
Ductbank-LMX
Full duct bank design and drafting toolkit — Excel calculation engine plus an AutoCAD add-in that draws the section automatically. Goes well beyond this free calculator's envelope sizing.