Electrical Conduit Installation

• Code Compliance: NEC-required depths (18–24 inches), proper bend radius, and pull string installation ensure inspections pass the first time.
• Long-Term Protection: Rigid PVC conduit protects wiring from moisture, rodents, freeze-thaw cycles, and accidental shovel strikes during landscaping.
• Safety First: Underground conduit eliminates overhead wires that can be struck by equipment, damaged by falling trees, or create fire hazards.
• Site Coordination: We work with power companies for transformer placement, licensed electricians for wire sizing, and inspectors for final approval.
• Cost Control: Efficient trenching, proper conduit sizing, and pull string installation minimize electrician labor costs and project delays.

Step 1: Load Calculation & Utility Coordination – We coordinate with your licensed electrician to determine wire size, conduit diameter (typically 1.5"–2" for residential service, up to 4" for commercial), and number of conductors. For new service entrances, we work with the power company to locate the transformer, meter pedestal, and primary connection point. For secondary runs (shops, wells, lighting), we confirm voltage, amperage, and whether conduit requires grounding conductor.

Step 2: Route Planning & 811 Locate – Conduit routes are planned to avoid existing utilities, septic drainfields, and obstacles. 811 locates are requested to mark underground power, gas, water, and communication lines. Trench depth is confirmed per NEC (18 inches for rigid conduit, 24 inches for direct burial cable in conduit, deeper under driveways). Long runs may require junction boxes or pull points to reduce wire-pulling friction.

Step 3: Trenching – Mini excavators, backhoes, or trenchers dig to specified depth and width. Rock is broken with hydraulic breakers if encountered. Trench bottom is graded smooth (no protruding rocks) to prevent conduit damage. Under driveways or roads, we trench deeper (24–36 inches) or install conduit in sleeved bores to protect from surface loads and frost.

Step 4: Conduit Installation – Schedule 40 PVC conduit is laid in trenches with proper sweep bends (minimum 36-inch radius for large conduit) to allow smooth wire pulling. Couplings are glued with PVC cement per manufacturer specs. Risers are installed at each end (with weatherheads for overhead connections or LBs for direct entries). Conduit is pitched slightly toward one end to allow drainage if water infiltrates. Pull string (nylon or polypropylene) is installed through the conduit for electrician use.

Step 5: Inspection, Backfill & Marking – Local inspectors verify conduit depth, coupling integrity, and proper bend radius before backfilling. Once approved, we backfill in 8–12 inch lifts, carefully compacting around conduit to prevent voids or shifting. Caution tape is placed 12 inches above conduit as a future locating aid. Final grade is restored, and conduit termination points are flagged or marked for electrician access. We provide as-built sketches showing conduit routes and depths.

• Equipment: Mini excavators, backhoes, trenchers, hydraulic breakers for rock, conduit benders, PVC cutters/saws, pull string installation tools, and compactors.
• Conduit Types: Schedule 40 PVC (gray) for most underground runs. Schedule 80 PVC (dark gray) for exposed risers or high-traffic areas. Rigid metal conduit (RMC) or IMC for above-grade runs or industrial applications.
• Conduit Sizes: Residential service: 1.5"–2" (100–200 amp panels). Shops/outbuildings: 1"–2" (varies by load). Well pumps: 1"–1.25". Site lighting: 0.75"–1". Commercial/industrial: 2"–4"+ depending on conductor count and sizing.
• Trench Depths: NEC minimums: 18 inches for rigid conduit (schedule 40/80), 24 inches for direct burial cable in conduit. Under driveways/roads: 24–36 inches or per local code. We typically trench to 24 inches for residential runs (provides extra protection and future-proofing).
• Bend Radius: Minimum 6× conduit diameter for smooth bends (e.g., 2" conduit = 12" radius). We use factory sweep bends or long-radius field bends to meet code and allow easy wire pulling.
• Site Conditions: We trench through clay, gravel, sandy loam, and decomposed granite. Rock excavation available with breakers. Long runs (>300 ft) may require junction boxes or pull points—coordinated with electrician during planning.