Depending on where you live, you might need a plumber’s permit or a mechanical permit. You’ll likely have to pay a fee to get it. Be sure to download a copy of your state’s plumbing code, too, as different states have specific requirements for gas pipe sizing. The size of your gas piping depends on both the length of the piping in your system and the total energy consumption of your appliances, which is measured in British Thermal Units (BTU). Find a copy of your state code on UpCodes to have as a handy reference. [3] X Research source
Let’s say that your gas line branches out to 3 appliances—a water heater that’s closest to the gas source, a dryer that’s second-closest, and a furnace that’s furthest away. You’d measure the total distance of the furnace to the gas source to get your LMR. As you study the logistics of your gas system, start creating a rough schematic for your new gas line. Sketch out all of the gas appliances that your pipes connect to, and where the gas lines exit your home. For your own reference, mark down how long each pipe section is. [6] X Research source
Your gas line connects to 3 appliances: a water heater, range, and clothes dryer. The LMR of this system is 65 ft (20 m), which you round up to 70 ft (21 m). The combined BTU of your appliances is 170,000 (or 170, abbreviated). Find the “70” row in the chart and trace your finger along the “Pipe Size” columns. A 1⁄2 in (1. 3 cm) pipe only supports 60 (60,000) BTU, which isn’t enough for your system. Same with the 3⁄4 in (1. 9 cm) pipe—it only supports 126 (126,000) BTU. A 1 in (2. 5 cm) thick pipe supports 237 (237,000) BTU, which is enough for the pipe segment in your gas line. Repeat this process with each segment in your gas line to calculate the necessary thickness.
Check with your local building department to see what details need to be included in your diagram. Check your latest utility bill to confirm if your home uses natural gas or propane.
When your gas is turned on, the lever will be parallel to the gas line. When your gas is turned off, the lever will be perpendicular. Most homes have 2 gas meters—one along the side of the home (the house-side shutoff), and another near the gas meter (the street-side shutoff). Whenever possible, always turned off the house-side shutoff valve, not the street-side one.
Use elbows and couplings to help angle and redirect your pipes in an efficient way through your home. Depending on the layout and structure of your home, you might need to run your gas line through your home’s walls and siding. Contact a licensed contractor if you aren’t comfortable doing this yourself.
Shutoff valves can be 6 ft (1. 8 m) away if you’re installing them near a dryer, and 4 ft (1. 2 m) away if you’re installing them near a log lighter.
Chances are, your pipeline will only experience 15-20 psi (103-138 kPa) of pressure—testing with 100 psi (689 kPA) is just a precaution.
Always inspect your pipes with soapy water, even if the pressure gauge doesn’t show any leaks. It’s always better to play it safe when you’re working with gas!
Depending on where you live, more than 1 inspection might be required. [17] X Research source Use this checklist as a reference to make sure you’re ready for the inspection(s). If you fail the inspection, the inspector will let you know what you need to fix.
