How Is Natural Gas Load Sized for a Commercial Laundry?

Every gas design I do for a laundry starts as a table: each appliance, its location, its fuel input rating from the manufacturer, and its operating pressure requirements. Dryers are listed by bank, water heaters and boilers by unit, and any space heating or auxiliary process load added in. I take very little diversity on the production equipment — a laundry earns its money when everything is running — and apply diversity only where operations genuinely justify it, such as office heating that cycles independently of production. That schedule becomes the basis for service sizing, meter selection, and regulator sizing, and it stays with the drawings so future equipment additions can be checked against available capacity.

With the load schedule set, I route the gas piping from the meter to each appliance and calculate pressure drop segment by segment, accounting for pipe material, fittings, and the actual connected load downstream of each point. Laundries punish lazy layouts: long straight runs to remote dryer rows, or a single trunk that was sized for half the machines, show up as pressure sag at the worst moment. I keep delivered pressure within the manufacturer's range for every appliance under full coincident load, place regulators and sediment traps where they can be serviced, and isolate equipment branches with accessible shutoff valves. The drawings show sizes, materials, and test pressures so the installer builds exactly what the calculations support.

The utility side of a laundry gas design deserves its own discipline: • Confirm total available capacity and delivery pressure at the property line before finalizing the design • Verify meter and regulator sizing against the full coincident load, not a diversified guess • Allow schedule time for utility upgrades — service lateral upsizing is measured in weeks, not days • Document the design load in writing so the utility's records match the building's needs • Plan for future growth: a capped tee and documented spare capacity make the next expansion cheaper