Phoenix is known for being on fire, I mean hot so we must love it to live here right? So it is no surprise that one of the hot topics for new homeowners and those wanting to remodel their Phoenix homes is the addition of natural gas lines or propane gas lines. Whether you’re wanting to add to your existing gas system or install gas lines from scratch there are a few things you need to know. We will cover the most frequently asked questions we get when it comes to residential gas lines in the Phoenix area and some of the basics of what you can expect when adding gas lines to your home.   

Frequently Asked Questions About Gas Lines in Phoenix

  • Can I tie into my existing gas line? 

We are asked this question multiple times a day, can I connect a gas line to my existing gas line? The request to add a gas appliance, like a gas dryer by tying into the gas line to the water heater is very common. The simple answer is, usually, NO. Gas lines are not like water lines that can often be tied into to add a plumbing fixture. Gas lines are sized originally to meet the requirements of the gas fixtures of the original installation. Gas lines are sized based on the length of the gas line and the BTU rating of the gas appliance so that the gas appliance gets enough gas to feed the flame and fuel demand when the appliance is in use. To add to the complexity of the situation the gas line only has roughly ¼ lb. of pressure, compared to your water line which should be in the range of 60-80 PSI. The low pressure of gas lines is the leading contributing factor of why it is impossible to add gas appliances to existing gas lines.  Imagine having trickling pressure at all of your faucets, showers and toilets and then wanting to add another shower to that same water system…your trickle quickly turns to a drip. Adding to an existing gas line could starve the appliances of the required gas it takes to run them. For example, if you have a gas water heater that required 55,000 BTU to run it and you tie in a gas dryer that requires 20,000 BTU to run, every time you turned on the dryer to dry your clothes you could starve your water heater of gas and potentially have both appliances not operate correctly or disrupt (blow out) the pilot on your water heater.  

The other con of adding to your existing gas system is testing your existing system.  While your gas lines only typically use ¼ pound pressure, these lines are tested at 10 PSI and older gas lines put under this pressure can often cause leaks at fittings that have to be traced down and fixed costing more money in the long run than just running a new gas line from the gas meter to the new gas appliance.

  • Do I need to get a permit for a gas new line if I already have a gas line on my property? 

The short answer, YES, absolutely. It’s wishful thinking that you don’t have to get a permit for a gas line, even replacing an existing gas line with a newer line requires a permit, and for good reason. Gas lines should not be messed with by anyone but a licensed professional and they should always be checked for perfection and code compliance, your life could depend on it. The permitting process can be a pain, especially after COVID, what used to be a walk in process that took a few hours is now an online process or setting up an appointment and can often take weeks to get, in the City of Phoenix. Some cities like the City of Scottsdale and the City of Glendale are still rocking permits out in less than a week but if you need a gas permit in the City of Phoenix, from our experience you need to prepare yourself for a 4-6 week wait time. Fortunately gas inspectors are still testing in a timely fashion so once the permit is posted and called in for inspection they are still testing the next business day. 

  • Can I increase the size of my gas oven or stove without increasing the size of my gas line? 

There isn’t a short answer for this question. This is a very common belief, but once you understand how gas works you’ll understand why increasing the demand on a gas line will not necessarily work out. This problem becomes apparent when homeowners want to increase the size or the on-demand features of gas appliances. A 4 burner stove doesn’t require as much natural gas as a 6-burner stove for example. Upgrading a gas stove that requires more BTU’s may cause your new stove to perform poorly or not at all. If your existing gas line was sized to accommodate a larger appliance in the future then the answer is yes, if it was not, then the answer is probably no.  

  • Do I have to replace my gas line to get a gas tankless water heater? 

The simple answer, usually no, you don’t have to increase the size of your gas line to get a gas tankless water heater.  There are certainly exceptions to this answer and it depends entirely upon the gas tankless unit you’re installing.  Many modern gas tankless water heaters are now designed to be condensing units so many manufacturers like Rinnai and Navien have built a condensing unit that uses an impeller on the internal gas valve to pull fuel in so that gas lines don’t have to be increased in size as long as the existing gas line meets the length requirements for the gas tankless unit. Not all residential gas tankless water heaters are created equal so this is something to be very mindful of when choosing one. We’ve had lots of clients buy a gas tankless water heater online at a “good” deal just to find when we go out to install them that the “good” savings didn’t add up when all of the plumbing upgrades were factored in. The incredibly frustrating part is a lot of online tankless water heater purchases are not returnable, buyer beware. 

  • What are the steps to getting a new gas line? 

Getting a new gas line to your home is not a DIY project in my personal and professional opinion.  Fixing a running toilet on your own is one thing, properly sizing, installing and passing inspection for a gas line is another process altogether.  

The process of getting a new gas line starts with very specific measurements and guidelines from the UPC (Uniform Plumbing Code) This code book is the bible for plumbers and it is what we are all held to. Plumbers are responsible for maintaining safety and proper installation of everything plumbing related. The Uniform Plumbing Code is what the Registrar of Contractors and inspectors of all municipalities like the City of Phoenix go by. Each jurisdiction is responsible for maintaining as a minimum the UPC, but has the right to have additional requirements above and beyond the standard plumbing code. Fun fact, the UPC book for 2018 has 54 pages (with small print) dedicated to just gas lines.  

Before you have the plumber out to start taking measurements and sizing your system based on plumbing code you will need to know what gas appliances you want installed and how many BTU’s and other specifications they require.  The plumber cannot guess on your system based on estimations, sizing a gas line is an exact mathematical equation so having this information is important.

The next step is for the plumber to draw up a schematic of your gas line, or in some cases the gas system for submission to the city for a permit. A gas schematic is more than drawing up a gas line, the city has exacting requirements of the schematic in order to submit for a permit. The city will inspect the schematic for accuracy on length of the gas line(s), the diameter of the gas line(s) and the BTU demand of the gas appliances being installed.  

After the schematic is finished the schematic is then submitted to the city per their system or protocol and a permit is requested. The next step is patience. Waiting for the gas permit after submission to the city can be frustrating.  Permits are issued on a first come first serve basis and some ques are backlogged for weeks. 

After the permit has been issued the licensed plumber can get to work.  Some gas lines are running above ground, some are below ground and require excavation, this all would have been planned out during the initial schematic and consultation period.  Gas lines have specific requirements on how they are run, for example if the gas line is going to be run below ground the plumber needs to know how deep they need to be buried, that they need to be buried with a tracer wire and other factors like running gas under foundations and what types of gas pipe and fittings are allowed to be used underground.

Once the gas system is installed the gas system is placed under test by pressurizing the line with air.  Each stub out and gas flex line is capped off and the line is pressurized with air and a gas pressure gauge is placed on the system.  The gas line is required by code to hold 10 PSI for 15 minutes while being inspected by the city inspector.  The plumber will pump up the system the day before inspection, and often during the winter time the plumber will return the morning of inspection to pump the line back up to 10 PSI as the ambient temperature can affect the pressure of the line because while it is hot out air expands and while it is cold the air contracts.  The line is perfectly safe, this is a natural occurrence of expansion just like frozen liquids expand in size. 

After the city passes inspection and posts a green tag the plumber will return and connect the gas appliances that are on site, if the line is not already connected to the gas meter the plumber will also do that while on site.  In some cases SWG (Southwest Gas) will come out to the site and turn on the gas.

Services in Phoenix & Beyond

When you’ve found yourself in need of plumbing services in the Phoenix, Glendale, Scottsdale, or Chandler area, you can trust Robins Plumbing to provide you with prompt and expert care, contact our team today! In addition to our toilet services, we also offer a variety of residential and commercial plumbing services, including: drain cleaning, water heater repair and replacement, sewer camera inspection and locating, backflow prevention, commercial and residential jetting, water treatments, trenchless sewer repair and more. Visit our reviews online to see what others have to say about our local plumbing company!