What are Chandler's rules for underground gas pipe?

The Gas Permits page of the Homeowner Building Permit Manual (Rev. 4/09/26) sets the rules in a few short lines. For metal pipe, the manual says: "All metal gas piping used in underground systems shall have factory-applied coating, and schedule 40 minimum weight." In other words, buried steel comes from the factory already coated, and nothing lighter than schedule 40 is allowed.

Field repairs to that coating are limited. The manual says: "Field wrapping is limited to fittings and short sections of piping, where the factory wrap has been damaged or stripped for threading or welding." It also sets the method: "Field wrapping is made with 2 layers of 20 mil tape with primer on the pipe and between each wrap."

Then the line this page is built on: "Galvanized fittings or piping are prohibited in underground gas systems."

For plastic, the manual says heat fusion PE (polyethylene) pipe needs a minimum 8, 12 or 18-inch deep trench depending on the situation and a "continuous insulated 18-gauge copper tracer wire." It adds: "PE is not allowed for use beneath any building slab or structure."

For a new line from the meter, the plans must show trench or burial depth, with the pipe 12 inches below grade minimum.

The parts, in short:

• Metal pipe: factory-coated, schedule 40 or heavier.
• Coating repairs: fittings and short damaged or threaded sections only, 2 layers of 20 mil tape with primer.
• Galvanized: not allowed underground, pipe or fittings.
• PE plastic: heat fused, tracer wire, never under a building slab or structure.
• Depth: 12 inches below grade minimum for a new line from the meter.

The code behind the manual is the 2024 International Fuel Gas Code, adopted by City Code 29-7. Chandler's only change to the IFGC is swapping Chapter 1 administration for the 2024 IBC's, so Section 404 applies as written. IFGC Section 404.11.1 backs up the galvanized ban: "Zinc coating shall not be deemed adequate protection for underground gas piping." IFGC Section 404.17.3 calls for "A yellow insulated copper tracer wire or other approved conductor" beside buried nonmetallic pipe, with access at each end, and IFGC Section 404.14 prohibits piping underground beneath buildings unless it is encased in an approved conduit.

• Schedule 40: a standard steel pipe wall thickness. The manual sets it as the minimum weight; it does not define the term.
• Factory-applied coating: the protective jacket put on the pipe at the plant, as opposed to tape wrapped on site.
• Field wrapping: tape applied on the job. Chandler limits it to fittings and short sections where the factory wrap was damaged or stripped for threading or welding.
• Heat fusion PE: polyethylene pipe joined by melting the ends together. The manual does not define it further.
• Tracer wire: a wire laid beside plastic pipe so the line can be located later. Plastic pipe can't be found with a metal locator on its own; that is our reading of why the rule exists, since neither source states the reason.

It covers anyone burying gas pipe at a Chandler home, natural gas or propane, whether the owner or a contractor does the work. The manual says: "Any construction requiring a permit also requires that a licensed contractor do the work unless the owner-applicant performs the work." For a rental home, the manual says a licensed contractor is required to obtain the permit.

This does not apply to piping above ground or inside the house; those runs have their own rules on our Chandler gas line permit page. It also does not cover the utility's service line up to the meter, which the manual's Gas Permits page does not address.

The pool heater run. A Chandler owner runs a new line from the meter across the backyard to a pool heater. They use PE pipe with a continuous insulated 18-gauge copper tracer wire, route it around the house rather than under it, and show the burial depth on the plans.

The damaged wrap. A contractor threads a coated steel line to add a tee. The threads strip the factory coating at that joint, so the fitting gets field wrapped: 2 layers of 20 mil tape, with primer on the pipe and between each wrap.

The leftover galvanized. An owner has galvanized pipe from an old project and plans to bury it. Chandler's manual rules that out, pipe and fittings alike.

The edge case: the patio slab. The model code lets plastic pipe run under outdoor patio, walkway and driveway slabs at full burial depth (IFGC 404.17.1, exception 3). Chandler's manual bars PE beneath "any building slab or structure." Our reading is that a detached patio slab is not a building slab, but a covered patio or ramada may count as a structure. Here the answer can flip, so ask the Plan Reviewer of the Day before you trench.

1. 1Call Arizona 811 (Blue Stake) before digging. The manual puts this on the homeowner and says to call at least two days before you dig.
2. 2Pick the pipe: factory-coated schedule 40 steel, or heat-fused PE with a continuous insulated 18-gauge copper tracer wire. No galvanized.
3. 3Draw the route from the meter with lengths, pipe size and type, appliance BTU ratings and burial depth, and keep PE away from any building slab or structure.
4. 4Apply for the gas permit through CLICS (developmentpermits.chandleraz.gov/clics) or at 215 E. Buffalo St. Unsure about a route? The manual points to the Plan Reviewer of the Day at 480-782-3078 or prod@chandleraz.gov.
5. 5Book the underground gas inspection, code 729 U/G Gas, through CLICS, the voice line at 480-782-3100, or by text to 844-281-3520. The pressure test rules are on our Chandler gas pressure test page.

If you'd rather not dig and document it yourself, HQ's licensed and insured plumbers do gas line work in Chandler, including yard lines for a grill or a pool heater.

• "Galvanized won't rust, so it's fine underground." Chandler prohibits it, and IFGC 404.11.1 says zinc coating is not adequate protection for underground gas piping.
• "Any tape works on bare spots." The manual limits field wrap to fittings and short damaged sections, with 2 layers of 20 mil tape and primer.
• "A short plastic run doesn't need tracer wire." Neither source gives a length exception.
• "8 inches is always enough for a grill line." The IFGC's 8-inch rule covers individual outdoor appliance lines, only where approved and not susceptible to physical damage. Chandler's manual lists 12 inches minimum for a new line from the meter.
• "Skipping the permit just costs the fee later." The manual says permit fees are doubled for building without a permit, and the city can order non-compliant work removed at the homeowner's cost.

This page explains Chandler's published underground gas rules as checked on the date above; the city's adopted code and Development Services govern any specific job.