Best Gas Line Plumbing Companies in Washington Ranked

Installing or repairing a gas line is a critical project that directly impacts the safety and functionality of your home. In Washington State, this work is governed by strict state and local codes to prevent leaks, fires, and carbon monoxide poisoning. This guide explains the process, regulations, and costs for gas line projects in Washington, helping you understand what's involved so you can find and hire a qualified local professional to ensure the job is done safely and correctly.

Anthony's Plumbing Company

2624 47th Ave SW, Seattle, WA 98116

Anthony's Plumbing Company is a licensed and insured plumbing service based in Seattle, WA. They provide residential and commercial plumbing solutions including gas line installation, drain repairs, and custom steam shower systems. The company emphasizes clean and professional work practices, using high-quality, safe materials and adhering to all code protocols. They offer free in-home consultations within their service area and have a strong focus on customer satisfaction, building lasting relationships with clients. Their service area includes multiple neighborhoods around Seattle and nearby cities.

5.0

238 Reviews

Action Craft Experts, Plumbing, Drains, & Water Heaters

spokane

Action Craft Experts, Plumbing, Drains, & Water Heaters is a locally owned plumbing company serving Spokane, WA, and surrounding areas including Northern Idaho. They provide a wide range of plumbing services for residential, commercial, new construction, and remodeling projects. Their licensed team handles water heater repair and installation, drain cleaning, sewer line repair, leak detection, and gas line installation, ensuring compliance with local codes and safety standards. With over 25 years of experience, they offer expertise in both traditional and tankless water heater systems and maintain an A+ rating with the Better Business Bureau. Action Craft Experts is licensed in Washington and Idaho and supports public works projects as well.

5.0

217 Reviews

Wesnor Plumbing and Heating

1705 N 82nd St, Seattle, WA 98103

Wesnor Plumbing and Heating provides a wide range of plumbing and heating services in Seattle, WA, including residential and commercial work. Their offerings cover water heater repair and installation, drain cleaning, sewer camera inspections, hydro jetting, leak detection, repiping, and gas line installation. They are authorized service providers for Rheem and Moen water heaters and hold a gas piping mechanic license, ensuring qualified handling of natural gas services. With extensive experience and licensed, bonded, and insured plumbers, Wesnor emphasizes quality workmanship and customer satisfaction. They also offer rapid response for flooding emergencies.

5.0

131 Reviews

Eco Electric, Plumbing, Heating and Air

126 S Spokane St, Seattle, WA 98134

Eco Electric, Plumbing, Heating and Air provides a range of home services in Seattle, WA, including leak detection plumbing and gas line installation. Serving the Puget Sound area, they offer electrical, plumbing, heating, and air conditioning solutions designed to improve home efficiency and sustainability. Their team brings over 10 years of combined experience and uses advanced technology for detailed inspections and durable repairs. The company is fully licensed, insured, and bonded, and offers financing options to help homeowners manage repair and upgrade costs.

4.9

2.0k Reviews

Pars plumbing

417 212th St SW, Bothell, WA 98021

Pars Plumbing is a plumbing service provider located in Seattle, WA, specializing in water heater repair and installation as well as gas line installation. They focus on delivering efficient and clean workmanship with attention to detail. Pars Plumbing is known for their thoughtful execution and clear communication throughout the project.

5.0

116 Reviews

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Understanding Washington's Gas Line Regulations

All residential gas line installation and repair in Washington is regulated by the International Residential Code (IRC) and the Washington State Fuel Gas Code, which are adopted and enforced by local building or public health departments ^{1 2 3 4}. The primary goal of these regulations is safety. Natural gas and propane are efficient fuels, but improper handling can lead to dangerous situations. Therefore, the state mandates that nearly all gas piping projects require a permit and a subsequent inspection to verify code compliance ^{1 5 6 7 8}.

Whether you're running a line for a new fireplace, outdoor kitchen, or furnace, the rules are designed to ensure the system is leak-free, properly sized, and correctly installed. These standards cover everything from the type of pipe used to how it is supported and tested.

The Step-by-Step Process for Gas Line Work

Navigating a gas line project involves a clear sequence of steps. Skipping any part of this process can result in failed inspections, safety hazards, and costly rework.

1. Determine Scope and Hire a Professional

First, define your project. Are you connecting a single appliance or running a new main line? In most areas of Washington, homeowners are legally permitted to perform gas line work on their own property, provided they obtain the proper permits and pass inspection ^{9 10}. A notable exception is the City of Seattle, where all gas piping work must be performed by a licensed professional ⁵.

For most homeowners, hiring a registered and bonded contractor is the safest and most efficient path. A licensed professional will be familiar with local amendments to the state code, can pull permits efficiently, and guarantees the work will meet inspection standards.

2. Obtain the Required Permit

A permit is required when you install, relocate, or change any part of a gas piping system ^{9 1 11}. You apply for this permit through your local jurisdiction-typically your city or county building department. In some areas, like King County, permits are handled by the Public Health department ^{12 13}.

The permit process ensures your project plans are reviewed for basic code compliance before any work begins. It also triggers the mandatory inspection schedule. Never proceed with gas line work without a permit; unpermitted work can void your homeowner's insurance, create problems when selling your home, and most importantly, pose a severe safety risk.

3. Plan and Design the System

Proper design is crucial for performance and safety. A key part of this is sizing the piping. The pipe diameter must be large enough to deliver sufficient gas volume (measured in BTUs per hour) to all appliances simultaneously, without a significant pressure drop ^{9 14}. A professional will calculate the total demand of your gas appliances and map out a system with correctly sized pipe runs.

This stage also involves selecting approved materials, such as black iron pipe or Corrugated Stainless Steel Tubing (CSST), and planning the route to avoid hazards and ensure proper support.

4. Install the Piping According to Code

Installation must follow Washington State Fuel Gas Code guidelines meticulously ¹⁵. Key requirements include:

• Support: Piping must be supported with galvanized metal straps or equivalent at least every 4 feet to prevent sagging and stress on joints ^{16 17}.
• Protection: Piping must be protected from physical damage. Underground plastic pipe (where allowed for propane) must be installed a minimum of 12 inches below grade and is for outdoor use only ^{18 19}.
• Corrosion Protection: All outdoor and underground ferrous (iron) piping must be protected with a suitable coating or paint to prevent rust ^{16 20}.
• Shutoff Valves: Each appliance must have an accessible, approved shutoff valve ¹⁰.

5. Pressure Test the System

Before the inspector arrives, the installer must test the system. After assembly, the entire piping system is pressurized with air or an inert gas (never oxygen) to at least 1.5 times its maximum operating pressure, but not less than 3 psi ^{9 21}. This pressure must hold steady for a specified period without dropping, which confirms there are no leaks. The test gauge used must have a maximum range no more than five times the test pressure for accuracy ²¹.

6. Schedule and Pass the Final Inspection

Once the pressure test is ready, you must schedule an inspection. The entire system must be exposed and accessible for the inspector's review ¹¹. They will check the installation for code compliance and typically witness a pressure test. Do not cover any piping or connect appliances before the inspection passes. Approval from the inspector is your official confirmation that the installation is safe and legal.

7. Connect Appliances and Activate Service

Only after receiving inspection approval can the final connections be made. Your gas utility company can then activate or connect the service. Appliances are connected to the system via their individual shutoff valves, and the system is purged of air with inert gas before being placed into service ^{9 22}.

Critical Safety Protocols for Gas Lines

Safety is the non-negotiable foundation of all gas line work. Adhering to these protocols protects your property and your family.

• Leak Detection: Never use an open flame to check for gas leaks. Always use an approved leak-detection solution (like soapy water) or a commercial gas leak detector ^{23 24}.
• Proper Purging: When placing new piping into service, air must be thoroughly purged from the lines using an inert gas to prevent creating a combustible mixture inside the pipe. This must be done with no ignition sources nearby ²².
• Approved Materials and Fittings: Use only pipe, fittings, and valves listed for gas service. Special ground joint unions are generally only permitted at the meter or after an appliance shutoff valve ^{9 10}.
• Licensing and Competence: Ensure anyone working on the system is knowledgeable and, where required by law, appropriately licensed. In Washington, a contractor must be registered and bonded to work on your property for hire ¹⁰.

Cost of Gas Line Installation & Repair in Washington

Pricing for gas line projects varies based on complexity, length of the run, materials, and local labor rates ^{25 26 27 28 29}. Below are general estimates to help you budget.

• Cost Per Linear Foot: On average, expect to pay between $25 to $50 per linear foot for installation, which typically includes materials and labor ^{9 30}.
• Appliance Connection Fee: Simply connecting a new appliance (like a dryer or range) to an existing gas line can range from $150 to $500, depending on accessibility and any minor adjustments needed ³¹.
• Total Project Costs:
  • Simple Projects: Adding a short line for a single new appliance often falls in the range of $500 to $1,500 ^{9 32}.
  • Complex Projects: Running a new main line to an outdoor feature (fire pit, grill) or installing lines for multiple appliances over a longer distance can range from $1,500 to $5,000 or more ^{9 33}.

These are estimates. For an accurate price, you must request a detailed, written quote from a licensed Washington contractor who can assess your specific site conditions and project requirements.

Common Materials Used in Gas Lines

Choosing the right material is part of the design process. The two most common types are:

• Black Iron Pipe: The traditional choice, known for its durability and strength. It requires threading and more labor to install but is highly reliable for both exposed and concealed runs.
• Corrugated Stainless Steel Tubing (CSST): A flexible, yellow-jacketed tubing that is easier and faster to install over long distances and around obstacles. It must be properly bonded and grounded to prevent electrical damage, as required by code ²⁵.

Your contractor will recommend the best material based on your project's layout, local code amendments, and safety considerations.

When to Consider Gas Line Repair

Repairs are needed when a gas line is damaged, shows signs of corrosion, or has a leak. Common indicators include:

• The smell of rotten eggs (odorant added to gas).
• Hissing sounds near a gas line.
• Dead or discolored vegetation in an otherwise healthy yard over an underground line.
• Higher-than-normal gas bills without increased usage.

If you suspect a leak, evacuate the area immediately and call your gas utility company or 911 from a safe location. Do not operate electrical switches or create any sparks. Repair work follows the same permit and inspection process as new installation to ensure the fix is permanent and safe.

Frequently asked questions

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