Confirm the fuel gas code and edition the jurisdiction enforces, then trace every gas-fired appliance through the equipment schedule, the gas piping plans and riser, its combustion air source, and its vent route and terminal. Compare each with the manufacturer’s installation instructions. AI can flag conflicts; the designer and code official decide compliance.
What does the IFGC cover?
ICC’s preface describes the International Fuel Gas Code as establishing minimum requirements for fuel gas systems and gas-fired appliances using prescriptive and performance-related provisions. It applies to all occupancies, including one- and two-family dwellings and townhouses. ICC also states that the IRC’s fuel gas chapter is composed entirely of text extracted from the IFGC, so a house project gets the same fuel gas provisions under either code.
ICC Digital Codes lists the 2027 IFGC as published, and ICC’s store lists the printed 2027 edition as coming in October 2026. Checked October 5, 2026. A jurisdiction enforces the edition it adopted, with amendments, and some adopt a different fuel gas code instead. Record which one the project uses.
Jurisdictions that adopt the National Fuel Gas Code follow the NFPA 54 guide, and liquefied petroleum gas storage follows the NFPA 58 guide. Ventilation and mechanical equipment beyond the gas system are covered in the IMC guide.
Gather every gas-fired appliance and its documents
Collect the gas piping plans and riser diagram, the gas load schedule or appliance list, the equipment schedules for boilers, water heaters, furnaces, rooftop units, kitchen equipment, and generators, the appliance installation manuals or product data, the vent and flue details, the combustion air arrangement, the roof plan with terminals, and the gas piping specification section.
An appliance’s installation instructions often decide its vent material and arrangement. Upload them, since a drawing note that conflicts with the selected appliance is exactly the kind of finding shown below.
Follow each appliance from supply to vent
| Review question | Sources to compare | Decision to record |
|---|---|---|
| Code and edition | Code analysis, plumbing and mechanical notes, specifications | Confirm which fuel gas code and edition each discipline cites. |
| Appliance inventory | Equipment schedules, gas piping plans, riser, load schedule | Match every gas-fired appliance across the schedules, plans, and load list. |
| Vent material and route | Vent details, appliance manuals, plans, roof plan | Check the vent type suits the selected appliance and the route and terminal are drawn. |
| Combustion air | Mechanical plans, architectural plans, appliance data | Identify appliances with no combustion air source or intake shown. |
| Piping and pressures | Riser diagram, piping plans, meter and regulator details, specifications | Reconcile pipe sizes, pressures, and regulator locations across sources. |
| Shutoffs and interlocks | Kitchen hood drawings, controls, electrical, specifications | Confirm shutoff valves and interlocks named in one document appear in the others. |
Commercial kitchens add hood and suppression interfaces in the commercial kitchen checklist, and boiler rooms the hydronic piping specifications guide. Large boilers can also fall under the NFPA 85 guide, and gas-fired engines and generators under the NFPA 37 guide.
Example: a vent note that does not suit the selected boiler
Published finding. In Groundbook’s published hydronic plant review, a vent detail called for a double-wall Type B gas vent at the hot water boiler, while the equipment schedule selected a condensing boiler whose installation manual requires a UL 1738 stainless steel vent system. A second finding noted that the plans showed no combustion air source and no vent route or terminal for the same boiler.
Type B vent is incompatible with the selected boiler. Replace the Type B note with a UL 1738 stainless-steel vent system approved for the boiler, state the chosen vent arrangement, and coordinate its route and termination.
The mechanical engineer selects the vent system and draws its route, terminal, and combustion air. The finding came from comparing a drawing note with the selected appliance’s installation manual, not from a calculation.
Review fuel gas coordination with Groundbook
Upload the current drawings and specifications to Groundbook, and state the edition, amendments, and review scope in your instructions. Add the IFGC edition the project uses from a copy you are licensed to use, where the license permits uploading it, and the jurisdiction’s published amendments. See how Groundbook works with local and licensed codes.
Compare the gas-fired appliances in the equipment schedules with the gas piping plans, riser, load schedule, vent and flue details, combustion air arrangement, roof terminals, appliance installation manuals, and specifications. Flag appliances missing from any source, vent materials that do not suit the selected appliance, and missing vent routes or combustion air. Use the supplied IFGC edition and cite both sources.
Groundbook links each potential finding to the sheets and product documents involved. Upload the appliance installation manuals as supporting documents so the comparison can use them.
Document review does not size gas piping or vents, calculate combustion air, or replace the designer, the gas utility, or the code official.