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Gas Pipe Sizing

Natural gas or LP-gas (propane)  ·  Schedule 40 metallic pipe & CSST  ·  Low pressure or 2 PSI — IFGC 2021 §402.4 | Longest Length Method §402.4.1

Step 1 — Floors & Appliances

Add floors, then add appliances to each floor. Set the CFH demand and EL distance (feet from meter, including fittings) for each appliance.

Step 2 — Meters & Circuits

One meter per unit or zone. Each circuit is one continuous pipe run from the meter. Assign appliances from Step 1. Use ↑↓ to order circuits — order affects trunk accumulation. All meters feed a single gas service entry.

Step 3 — Sizing Results
Complete Steps 1 and 2 to see results
Riser Diagram
Assign fixtures to circuits to generate diagram
Text Output
COMPLETE STEPS 1 AND 2 TO GENERATE OUTPUT
Preliminary design only. Verify with a licensed engineer or plumbing contractor before construction or permit submission. EL including fitting allowances is the designer’s responsibility. CFH = nameplate input BTU/HR ÷ (1,000 for natural gas; 2,516 for LP/propane) — not efficiency-adjusted output. Sizing per IFGC 2021 §402.4.1 Longest Length Method / NJ UCC Fuel Gas Subcode 2021. Natural gas: 1,000 BTU/CF, SG 0.60. LP-gas (propane): 2,516 BTU/CF, SG 1.50. NG Sch 40 per Table 402.4(2)/(5); LP Sch 40 per Table 402.4(28)/(27). NG CSST per Table 402.4(15); LP CSST per Table 402.4(32). CSST tables include 4 × 90° bends and 2 end fittings. Green Stories LLC is not a licensed engineering firm.