Black iron, CSST, or copper—calculate the full installed cost including fittings, pressure test, shutoffs, and permit so your gas line quote doesn't spring a leak in your margin.
Unpermitted gas work is a homeowner's insurance policy voiding event. If a gas leak causes a fire and the work was unpermitted, the insurer denies the claim and you're liable. Always pull the permit, pay the fee, and schedule the inspection. "The customer didn't want to pay for the permit" is not a defense. Build the permit into every gas quote as a non-negotiable line item.
CSST is faster to install than black iron but requires bonding per NFPA 54. Some jurisdictions require a dedicated CSST bonding clamp at every 50 ft of run or at every fitting. If your local AHJ enforces this strictly, add 30–45 minutes of electrical coordination and material to the quote. An unbonded CSST installation fails inspection and you pay for the return visit.
A ½″ line that's adequate for a gas range fails when the homeowner adds a generator, gas dryer, or pool heater next year. Run pipe size calculations based on total BTU demand plus 20% buffer. CSST is easier to oversize because it's flexible—black iron upsizing costs real money in fittings and time. Get the load information during the estimate visit.
The Plumber's Business Starter Kit includes a flat-rate price book for 40 common plumbing and gas jobs, a service agreement template, and a morning dispatch checklist. Guide from $19 — Complete Kit with all 19 templates, $49.
Get the Plumber's Kit →Gas line work carries real liability, and pricing it correctly means accounting for pipe size, run length, connection type, pressure testing, permit fees, and inspection. This calculator builds a complete gas line installation price from each component so your quote reflects the actual scope of the work. Use it for new appliance connections, range installations, generator feed lines, and outdoor grill or fire pit connections.