Hours vary Denver (720) 951-4619
Call (720) 951-4619
Residential Underground Wiring: Licensed, Permitted, Buried Right

Chapter 06 · Wiring, Repair & Code

Residential Underground Wiring: Licensed, Permitted, Buried Right

Cleaner property lines, fewer outages, and wiring that meets Colorado code.

Call now(720) 951-4619
Call (720) 951-4619Request an estimate

Free estimate

Tell us what you need

Three fields. It reaches a person here, not a call centre.

No obligation · Responds within 1 business day

By submitting this form you agree that we may contact you about your request and share your details with partner companies for marketing purposes.

What Residential Underground Wiring Actually Involves

Residential underground wiring runs electrical conductors below grade rather than overhead or exposed along exterior walls. Homeowners choose it for three reasons: it removes visible conduit from the property, it reduces vulnerability to weather disruptions, and it protects conductors from accidental damage. All Electric installs underground wiring systems to Colorado code under CO License #ME.0600978, with a 1-year labor warranty on every job. Call (720) 951-4619 to schedule a site assessment.

The installation process involves trenching, selecting the correct conduit type (PVC or rigid metal depending on depth and soil conditions), pulling the appropriate wire gauge for the load, and terminating at both ends with weatherproof connections. Depth requirements vary by circuit type under the NEC: low-voltage landscape circuits go shallower than 120V or 240V residential feeders, which typically require 24 inches of cover in direct-buried conduit. Scope, soil conditions, trench length, and panel proximity are the primary cost drivers on any underground wiring project. Every job is different, contact All Electric for an accurate estimate.

Benefits of Burying Your Electrical Wiring

Underground systems outperform overhead runs in four measurable ways.

  1. Aesthetics

    Buried wiring eliminates exposed conduit along siding, fence lines, and outbuildings. The finished result looks like the wiring was never there, because it isn't visible.

  2. Reliability

    Underground cables aren't affected by wind, ice loading, or falling branches. Front Range weather can knock out overhead service lines; buried conductors stay protected.

  3. Safety

    Conduit and burial depth keep conductors away from lawn equipment, pets, and foot traffic. Properly installed underground systems also reduce arc-flash exposure at the structure.

  4. Scalability

    Existing underground conduit accepts additional conductors without re-trenching. If you add a shop, EV charger, or outbuilding later, the infrastructure is already in the ground.

Real Challenges

Underground Wiring Has Trade-Offs Worth Knowing

Honestly, underground wiring isn't always the right call, and any electrician who sells it universally isn't thinking through your specific property. Installation costs run higher than overhead wiring because trenching is labor-intensive and the material requirements are stricter. Locating a fault in a buried conductor also takes specialized equipment. You can't just trace it visually the way you can with an overhead run. That said, for most permanent outdoor circuits (subpanels, detached garages, hot tub circuits, landscape power), the long-term durability and cleaner appearance make underground the better investment. If you're weighing the options, it's worth reading our notes on aluminum wiring repair as well, older overhead systems sometimes carry aluminum conductors that complicate any upgrade.
aesthetics work, professional service in Denver, CO

How It Works

From Trench to Termination: The Installation Process

  1. Step 1: Site Assessment and Permitting

    We confirm the circuit load, trench route, burial depth requirements, and permit needs before any digging starts. Most underground residential circuits require a permit in Colorado, we pull it.

  2. Step 2: Trenching and Conduit Installation

    We excavate to the code-required depth, install conduit (PVC or rigid metal as required), bed it properly, and inspect before backfill. The conduit protects conductors and allows future wire pulls.

  3. Step 3: Wire Pull and Termination

    Conductors are pulled through conduit and terminated at both ends with weatherproof connections. We test the circuit under load before the trench is closed and the ground restored.

What All Electric Handles on Underground Wiring Jobs

These are the specific tasks covered on a typical residential underground wiring project.

  • Load calculation and circuit sizing

  • Permit application and inspection

  • Utility locates (811) before any digging

  • Conduit selection and wire pull to code

Common Underground Wiring Applications

Underground circuits serve several distinct use cases, each with different depth and conduit requirements.

01

Detached Garages and Shops

A subpanel feed to a detached structure is one of the most common underground wiring jobs. It supports lighting, receptacles, and dedicated circuits for equipment. We size the feeder for current and future load.

02

Hot Tub and Spa Circuits

Hot tubs require a dedicated 240V underground circuit with GFCI protection and a disconnect within sight of the spa. NEC Article 680 sets the specifics, we install to that standard.

03

Outdoor Lighting and Landscape Power

Low-voltage landscape systems and line-voltage outdoor lighting installation both benefit from buried wiring. It removes trip hazards, protects conductors from UV, and keeps the yard looking clean.

04

EV Charger Runs

When the garage panel can't support a Level 2 charger without a long overhead run, an underground feeder from the main panel is often the cleaner solution. We handle the full run.

Why Homeowners Call All Electric First

  1. Step 1: Licensed and Permitted Every Time

    CO License #ME.0600978. We pull permits on underground work. Not because we have to, but because unpermitted buried circuits fail home inspections and create insurance issues.

  2. Step 2: 4.9 Stars Across 468 Google Reviews

    Daniel Vargas has been doing this work for 9 years. The review count reflects real volume, not a handful of asks from friends. Read them at our Google Business Profile.

  3. Step 3: 1-Year Labor Warranty

    Every underground wiring installation carries a 1-year warranty on labor. If something isn't right, we come back and fix it. Financing is also available for larger projects.

Straight from Google

What Customers Say

4.9468 verified Google reviews
Got the job done well, pleasant to work with.
Brian NicholsBrian NicholsSep 2026 · Google
All Electric is the best! Knowledgeable in fair and troubleshoot till they get the job done, if needed. Highly recommend 🙌🏽
gina dgina dSep 2026 · Google
Fantastic service. They showed up, assisted in the repairs, found the underlying issues and fixed them and then explained what those issues were in a manner that I could understand. Top service, as always.
Sean FrohlingSean FrohlingAug 2026 · Google
Same day service! Was here in 3 hours. Very honest and charge was kept at the minimum. Polite service as well.
Fred LudlowFred LudlowAug 2026 · Google
Very responsive. Easy to work with. Would definitely recommend to friends and family.
BritneyBritneyAug 2026 · Google
Electrician came out the next day after calling to install two light fixtures. Minimal issues and got them both installed successfully even though we have an old home. Pricing was reasonable to me. I will definitely be using them again for any similar needs!
Jillian L. CallaghanJillian L. CallaghanAug 2026 · Google
Awesome service. Quick prompt and very professional and knows the business. Daniel Vargas was the Master Tech. Accessed the problem and was quick to diagnose! Two faulty breakers. Highly recommend.
Michelle BakerMichelle BakerAug 2026 · Google
Daniel was great - solution-oriented, super-responsive, knowledgeable and really nice to work with - I will look to Daniel aand All Electric for future needs - thanks!
Travis BoganTravis BoganAug 2026 · Google
Read all 468 reviews

Underground Wiring: Common Questions

Not answered here? Call (720) 951-4619 and ask the electrician.

How deep does underground wiring need to be buried in Colorado?
Depth depends on conduit type and circuit voltage. Under the NEC, direct-buried cable (no conduit) for a 120/240V circuit requires 24 inches of cover. Conductors in PVC conduit require 18 inches. Rigid metal conduit drops to 6 inches. Low-voltage landscape wiring can go as shallow as 6 inches. Colorado inspectors enforce these minimums. We don't cut corners on depth because an inspection failure means digging it back up.
Do I need a permit for underground wiring at my house?
Yes, in virtually every Colorado jurisdiction. A trench for a 240V circuit feeding a garage, hot tub, or outbuilding is a permitted electrical installation. All Electric pulls the permit before work starts and schedules the inspection. Skipping the permit creates problems at resale and can void homeowner's insurance on work that wasn't inspected.
What type of conduit is used for residential underground wiring?
The most common choice for residential underground work is Schedule 40 PVC conduit at 18 inches of cover, or Schedule 80 PVC where the conduit emerges from grade and is exposed. Rigid metal conduit is specified when the run passes through areas with mechanical damage risk or when the inspector requires it. We assess each trench route before specifying conduit type.
How do you find a fault in a buried underground circuit?
Locating a fault in a buried conductor requires a time-domain reflectometer (TDR) or similar diagnostic equipment. Unlike overhead wiring where you can trace visually, underground faults aren't visible. This is one reason proper conduit installation matters so much. If conductors are in conduit, a damaged wire can be pulled and replaced without re-trenching. Direct-buried cable with a fault means excavation.
Can I run a 220-outlet circuit underground to a detached garage?
Yes, and it's one of the most common underground wiring applications we handle. The feeder is sized based on the panel capacity in the garage and the anticipated load. We install a subpanel in the detached structure fed by an underground feeder from the main panel. See our 220-outlet installation page for more on circuit sizing. Every job is different, contact All Electric for an accurate estimate.
How do you do underground residential wiring safely?
Safe underground wiring starts with a utility locate call (811) at least three business days before any digging. From there: trench to code depth, install approved conduit, pull correctly sized conductors, terminate with weatherproof fittings, and schedule inspection before backfill. The inspection step is non-negotiable. An uninspected buried circuit with a termination problem won't show up until something fails, sometimes years later.
Do I need a permit for underground wiring at my home?
Yes, in virtually every Colorado jurisdiction. A trench for a 240V circuit feeding a garage, hot tub, or outbuilding is a permitted electrical installation. All Electric pulls the permit before work starts and schedules the inspection. Skipping the permit creates problems at resale and can void homeowner's insurance on work that wasn't inspected.
What type of conduit is required for residential underground electrical work?
The most common choice is Schedule 40 PVC conduit at 18 inches of cover. Schedule 80 PVC is used where conduit emerges from grade and is exposed to mechanical damage. Rigid metal conduit is specified when the inspector requires it or the trench route passes through a high-risk area. We assess each route before specifying conduit type. There's no single answer that works for every property.
How do you locate a fault in a buried underground circuit?
Locating a fault in a buried conductor requires a time-domain reflectometer (TDR) or similar diagnostic tool. Unlike overhead wiring, underground faults aren't visible. This is one reason proper conduit installation matters, conductors in conduit can be pulled and replaced without re-trenching. Direct-buried cable with a fault typically means excavation.
Can a 240V circuit be run underground to a detached garage or outbuilding?
Yes, and it's one of the most common underground wiring jobs we do. The feeder is sized based on the subpanel capacity and anticipated load in the structure. We install the subpanel in the outbuilding and run an underground feeder from the main panel. Every job is different, contact All Electric for an accurate estimate.
What happens if underground wiring isn't installed to code?
An uninspected or under-depth installation creates several problems: it fails home inspection at resale, can void homeowner's insurance coverage for related damage, and presents a genuine safety risk if conductors are too shallow and subject to mechanical damage. All Electric pulls permits and schedules inspections on every underground project, CO License #ME.0600978.

Schedule Your Underground Wiring Assessment

All Electric handles residential underground wiring from permit to inspection across the Front Range.

Call the shop

(720) 951-4619
  • Mon to Fri: 5 AM to 9 PM
  • Sat and Sun: 7 AM to 8 PM
Request an estimate