Can Gas Lines Run Under A House? (Explained)

Disclaimer: This post may contain affiliate links, meaning we get a small commission if you make a purchase through our links, at no cost to you. For more information, please visit our Disclaimer Page.

Neither chimneys nor ducts can be used to run gas piping. Unless there is an exception, most appliances need to have shut-off valves nearby. The majority of municipalities do not permit gas piping to be used for grounding as electrical services.

Several gas meters located on the wall of a residential building

Can You Run a Gas Line under a Concrete Slab?

The IFGC Commentary specifies that you can install the pipes within an open channel under concrete slabs. Besides the conduit extending 2 inches beyond the slab, the only discussion involving size is whether or not the conduit can be tightly sealed.

Aside from that, section G2415.4 (404.4), which is piping through solid partitions and foundation walls, states that “concealed piping shall not be located in solid partitions and solid walls, unless installed in a chase or casing”.

If you’re planning on running the pipes through foundation walls, section P2603.4 states that ” a pipe that passes through a foundation wall shall be provided with a relieving arch, or a pipe sleeve shall be built into the foundation wall.”

The sleeve(s) used should be two pipe sizes larger than the pipe you are planning to run through the wall.

I highly recommend checking out those 2 links as they direct you to the International Residential codes and in some of the sections, you can some picture examples that may be helpful.

It’s also best that you seek the advice of a licensed professional to see if there’s any other codes you have to follow such as country or state specific building codes.

Can Gas Lines Run under the House?

There can be no gas piping running through chimneys or duct systems. Many appliances should have a valve next to them that provides an emergency shut-off.

Gas piping cannot be used to ground electrical services in most places.

Connecting Gas Pipe Lines

You can connect your oven or dryer to the gas line pretty easily – most of the parts need to be screwed together. It’s important to be aware of a few things when choosing which fitting to use.

Using the wrong one might cause a leak. Home centers and hardware stores sell kits containing stainless steel flexible gas lines and fittings.

It’s usually included in the kits, but you might need to buy extra fittings in some cases.

However, you should first check with your local building inspection department to find out if you can hook up your gas dryer.

You must seek assistance when you purchase the parts. Make sure that all parts of the gas line fit together by screwing them all together.

Make Connections to Steel Gas Pipe

You will need a gas appliance connection kit to connect your old appliance to a steel gas pipe. You should replace steel gas lines with stainless steel tubes for flexible gas supply lines.

Directly connecting a flare fitting to a steel pipe thread will not work on flexible gas lines. This kit includes a flare fitting that must be installed.

Make sure to apply pipe thread compound to all threaded pipe connections before assembly.

Use an existing bushing to reduce the female pipe thread from 3/4″ to 1/2″ if necessary. Pushing the stove against the wall requires a 90-degree elbow to prevent the gas tubing from kinking.

Replace a gas valve only after you have found and closed off the main gas valve in your house. Near the entrance to the house, the main gas valve is usually found.

Use modern gas valves that are marked for use with the gas to replace old gas valves. When you are finished, turn back on the gas. Don’t forget to check that your gas appliances have a pilot light that needs relighting.

Connections to Soft Copper

Soft copper tubing is connected by flaring each end with a special flaring tool using flare fittings with matching cone-shaped meeting surfaces.

Flare fittings are usually available in 3/8-inches, 1/2-inches, and 5/8-inches.

Connect flare fittings to the soft copper with an outside diameter that matches the inner diameter of the flare fittings. Connect a new length of soft copper coiled around a flare fitting by flaring the ends.

Use flexible stainless connectors instead of replacing the damaged tubing. It is possible to screw on the flare fitting on the stainless flexible gas line if it corresponds to the existing flare fitting.

Replacement valves with flare fittings on one side and pipe threads on the other might work when the fittings don’t match. The flexible gas line can be connected to the hookup kit using the adapter.

You will need a flare-to-pipe-thread fitting at the stove end. Before assembling threaded connections, apply Teflon tape. Unlike other joints, flare joints require no additional sealant to seal.

Reuse a Soft Copper Coil

A coil of soft copper is commonly used for connecting appliances. Unlike traditional copper tubing, the copper tubing ends will be flared. The conical fitting and the flared end of the tube form a leak-proof joint when they are perfectly fitted together.

Connect the new appliance to the soft copper tubing as long as it isn’t damaged or kinked. To solve the problem, you can buy a brass elbow with a flare fitting.

There is a possibility that your tubing and appliance have different thread sizes. Make sure to buy matching fittings. Before assembling, use tape rated for gas to get the outcome.

Ensure the copper tube fits perfectly before attaching the flare nut. Apply a closed-end or adjustable wrench to the nut. Swab each joint with 2 tsp of solution after turning the gas back on.

Use a leak testing solution prepared with dishwashing liquid and water. Look for bubbles forming on each connection. To fix a leaky connection, turn off the gas and tighten the leaky connection.

It may not work, so take it apart. Be on the lookout for debris and damage to flare connections. Reapply Teflon tape or pipe joint compound to threaded connections and reassemble the fitting to seal leaks.

How Deep Should the Gas Line Be under the House?

The local authority regulates how deep to bury gas lines. Because of this, the depth to which gas lines can be buried varies by state and county.

The typical gas main is 24 inches deep, while the typical service line is 18 inches deep.

Considerations When Planning Gas Pipe Installation

You must be extremely cautious when altering or updating gas appliances since gas lines run underneath and through your home.

Installing gas pipes can be essential when you move to a new house or renovate an old one. Learn how to plan for a gas pipe installation by considering three critical factors.

Trust the Professionals

Homeowners should not attempt to handle gas appliances or systems on their own because they can be extremely dangerous. You should achieve safety and code compliance by hiring a licensed and skilled professional.

Licensing professionals are not only knowledgeable and equipped to handle your job, but they are usually legally certified.

Trying to do it yourself without the assistance of a licensed professional can result in gas leaks and other dangerous consequences. You do not want to take the risk of causing damage to your family or home.

Check the Pipes

As the years go by, gas pipes may become corroded and may pose other problems. As a homeowner, you can examine your gas pipes, but a licensed professional will check them when they arrive.

Ensure that the licensed professional is aware of any issues visible in the pipes by using a flashlight when the professional arrives. Make sure that your pipe system is checked yearly if your home is older.

Time for New Appliances

If you notice any issue with the appliances, try replacing them. If the appliances run on natural gas, gas ovens and stoves can be connected to a home’s heating system.

You can find a variety of gas appliances that are superbly designed and very efficient, from gas furnaces to gas dryers.

copper pipes and fittings for carrying out plumbing work


You should not run the gas lines under your house without any professional assistance. Getting help from a professional can save you from a disaster.

Professionals will help you know whether it’s a good idea to install the gas lines under the house or not.

If experts do not recommend running the gas line under the house, avoid it for your safety. If you notice any smell coming from the gas line, you should also contact a professional to fix it. Professionals should install gas lines properly.

To prevent your home from becoming a fire prevention statistic, have your home professionally inspected if you use gas-powered appliances.

To ensure safety and quality, choose licensed professionals for gas line addition, update, or repair in the home. So, be careful while dealing with the gas line.