Start at the meter or LPG tank and trace each gas run to its appliances: confirm the pipe or tubing material the drawings label is one the issued Section 23 11 20 keeps, that the main shutoff, line and appliance regulators, and their vents are drawn where indicated, and that any automatic or seismic gas shutoff the section keeps appears on the plans. Then check concealed and buried piping, final connections, fire seals, bonding, and the test and purge requirements against the drawings and the appliance schedules.
Assemble the review package
Gather the gas piping plans and riser or isometric, the site utility plan showing the service, meter, or LPG tank, the equipment and appliance schedules with gas loads and pressures, the roof plan for regulator vents and rooftop units, the architectural rated wall and floor plans, the electrical grounding drawings, the structural or seismic criteria, and the issued Section 23 11 20 with Section 33 51 15 if the utility service is in scope. Review one branch from the meter to its farthest appliance before assuming the others match.
WBDG publishes UFGS 23 11 20: Facility Gas Piping as a public guide-specification reference (accessed October 21, 2026). Use your project’s issued specification and amendments for the actual comparison; the guide specification does not automatically govern your project. The checklist below is an original suggested review workflow, not a reproduction of the UFGS requirements.
Eight checks to run against the issued set
Use one record per location or system. The CSV contains the same eight prompts plus fields for source revisions, observed evidence, the review owner, the decision, and closure references.
| Check | Sources to compare | Question to resolve |
|---|---|---|
| Scope boundary at the building | Section notes + site utility plan + gas plans | Is the point where Section 33 51 15 ends and Section 23 11 20 begins clear on the drawings, with the meter, service regulator, and service shutoff assigned to one section? |
| Pipe and tubing materials | Gas Piping System and Fittings article + gas plans and isometric | Does each material labeled (steel, copper, aluminum, CSST, thermoplastic, or fiberglass) appear in the edited section, and are plastic materials kept to the locations the section allows? |
| CSST protection | Corrugated Stainless Steel Tubing article + architectural details | Where CSST is used, are striker plates and manifolds shown or noted where tubing passes through framing? |
| Main shutoff and branch valves | Valves and Shutoff Valve articles + gas plans | Is the main shutoff drawn where indicated and accessible, with the shutoff on the riser outside the building and the stop valve on the service branch that the section asks for? |
| Regulators and vents | Line and Appliance Regulators and Shutoff Valves and Line and Appliance Pressure Regulators articles + roof and wall plans | Is each line and appliance regulator shown with an upstream shutoff, and where a vent limiting device is not used, is the vent drawn to the outside and away from openings? |
| Automatic and seismic shutoff | Automatic Gas Shut-Off and Seismic Provisions articles + gas plans + seismic criteria | If the section keeps an excess flow valve or an earthquake shutoff valve, is it drawn at the location the bracketed option selects, at the meter or tank or at each appliance branch? |
| Concealed, buried, and final connections | Piping and Tubing Buried Under Buildings, Concealed Piping in Buildings, and Final Gas Connections articles + plans and details | Is gas piping under a slab shown in a casing or listed encasement with a vent, and are flexible connectors limited to the locations the edited section permits? |
| Fire seal, bonding, and testing | Fire Seal, Electrical Bonding and Grounding, Testing, and Purging articles + rated plans + grounding drawings | Do rated crossings point to Section 07 84 00, is the gas piping bonded on the grounding drawings, and does the test plan include pressure testing and purging before appliances are connected? |
Worked example: a regulator vent ending under a canopy
Illustrative example: the gas riser shows a line pressure regulator inside a mechanical room serving rooftop units and a kitchen. The issued Section 23 11 20 requires a vent to the outside where the regulator has no vent limiting device. The gas plans show the vent terminating on the exterior wall directly below a loading dock canopy and next to an outdoor air intake drawn on the mechanical plans.
Ask the mechanical or plumbing engineer to confirm whether the regulator has a vent limiting device, and if it does not, to relocate the vent termination to a point where gas can escape freely, coordinated with the intake and canopy. Recheck the other regulator vents on the roof plan against nearby intakes and openings before closing the item.
Avoid a false conflict
Gas pressure, pipe sizing, and appliance input usually live on the gas riser and the appliance schedules, not in Section 23 11 20. A material or regulator that looks wrong in the specification may be correct for a pressure the drawings show, so compare the two before raising a conflict.
When requirements disagree, follow the project’s document-control and clarification process. Do not assume that drawings always override specifications, or the reverse. Identify the exact sources and request an authorized decision.
Close the issue across the affected documents
Record the location or tag, drawing and specification references, issue dates, observed difference, and the decision needed. Assign an owner and keep the item open until the response identifies the governing requirement. Check the revised drawings and specification references together; a response email alone may leave the issued package inconsistent.
For the overall process, use the guide to drawing and specification conflicts. Mark an inapplicable checklist row with a reason, and distinguish a verified correction from a question that still needs design information.
Where Groundbook fits
Groundbook’s drawing and specification review helps investigate potential disagreements in the documents you supply. Include the relevant specification sections and drawing references, then verify the cited evidence with the responsible reviewers before acting on a finding.