Gas Lines for Grills, Fire Pits and Outdoor Kitchens in Spartanburg

The standard for buried gas lines is yellow polyethylene (PE) pipe. It does not corrode like buried steel, it handles shifting soil, and it can be run in long lengths with few joints. It is rated for use underground only, so it never runs exposed to sunlight or inside a building.

The fuel gas code sets a minimum burial depth of 12 inches, with a reduced 8 inches allowed for a line feeding an individual outdoor appliance like a grill or a lantern. We often go deeper where the line crosses a lawn that will be aerated, a garden bed that will be tilled, or ground that might see a fence post or a sprinkler line later. Rocks and debris stay out of the backfill around the pipe.

Because plastic pipe cannot be found with a metal detector, the code requires a tracer wire buried alongside it. That wire is how a locator finds your line years later. Since SC811 will not mark it, the tracer wire and the notes we leave you on the route are what keep a future fence crew or landscaper from hitting it.

Where the line comes out of the ground, it transitions from PE to steel through a riser. Factory risers have the transition built in and a protective coating where the pipe passes through soil, which is the zone where bare steel corrodes fastest. The riser is anchored to something solid, such as the kitchen frame, a post or the house wall, so it is not bumped loose.

Every outdoor appliance gets an accessible manual shutoff valve. For a built-in grill or a fire table, it is near the appliance and reachable without taking the island apart; access panels and doors in an outdoor kitchen are planned for it.

A freestanding grill that rolls around the patio connects with a listed quick-disconnect coupling and a hose made for outdoor gas appliances. The code requires a manual shutoff upstream of the quick-disconnect, and the coupling shuts off automatically when the grill is unhooked. That lets you move the grill to clean or store it without leaving an open gas line.

Most grills sold off the floor are set up for propane cylinders. To run one on natural gas it needs the manufacturer's natural gas version or conversion kit, which changes the burner orifices and removes the propane regulator. Some models offer no conversion at all, so check before you buy. A grill running on the wrong fuel burns poorly and can flare dangerously.

Fire pits and fire tables are listed for one fuel too, and they come with a manufacturer's minimum supply pressure and a BTU rating that can be higher than people expect. A large fire table can draw as much as a furnace. We size the line from the rating plate and check the flame height and pattern on startup.

Placement matters as much as the gas. Grills and fire features have listed clearances to combustible walls, railings and overhead structures. A grill tucked under a low covered porch, or a fire table under a pergola with a solid roof, has to meet the clearances in its manual.

The best time to run an outdoor gas line is before the patio, the pavers or the deck go down. A sleeve under a new patio costs little to place during construction and saves cutting concrete later. If you think you will want a fire table next year, it is far easier to stub a capped line to that spot now.

Outdoor appliances add to the house load. A grill, a side burner and a fire table together can be a meaningful draw, and a pool heater is often the largest gas appliance on the property. We size the outdoor branch and check that the line back toward the meter can carry it with the furnace and water heater running.

Where the line starts matters too. A tie-in near the meter, a branch in the crawlspace, or a connection at the house wall each have trade-offs in length, digging and how much of the existing piping has to be upsized. We walk the yard with you and lay out the route before we dig.