Plumbing Estimating Guide: Pipe, Fixtures, and Equipment Quantification

By F&K Estimatings Team

Plumbing estimating involves quantifying water supply, drainage, vent systems, fixtures, and specialty systems like medical gas. The wide variety of pipe materials, fitting counts, and code requirements makes this a detailed trade to estimate accurately.

Division 22 Scope

CSI Division 22 — Plumbing covers:

22 05 00 — Common Work Results for Plumbing
22 10 00 — Plumbing Piping (domestic water, drainage)
22 20 00 — Plumbing Fixtures (toilets, sinks, faucets)
22 30 00 — Plumbing Equipment (water heaters, pumps)
22 40 00 — Plumbing Specialties (backflow preventers, grease traps)
22 50 00 — Pool and Fountain Plumbing
22 60 00 — Medical Gas Systems

Pipe Takeoff

Domestic Water

Copper (Type K, L, M) or PEX by diameter (1/2” to 4”)
Valves: gate, globe, check, ball, pressure-reducing
Insulation: foam or fiberglass by thickness
Hangers and supports: spacing per code

Drainage and Vent

PVC (DWV Schedule 40), cast iron (hubless or no-hub) by diameter
Fittings: wyes, tees, elbows, bends, clean-outs
Slope: 1/4” per foot (typical for 3” and smaller)

Natural Gas

Black iron or CSST by diameter
Valves: gas cocks, excess flow valves
Regulators, meters, drip legs

Fixture Counts

Fixture Type	Typical Units
Water closet (flush valve)	1.28 GPF
Water closet (tank-type)	1.6 GPF
Urinal (flush valve)	0.5 GPF
Lavatory faucet	0.5 GPM
Sink (mop/service)	3.0 GPM
Drinking fountain	Bubbler or bottle filler

Medical Gas Systems

Medical gas estimating is highly specialized:

Oxygen, medical air, vacuum, nitrous oxide, nitrogen
Type K or L copper per NFPA 99
Zone valves, alarms, outlets (gas-specific)
Testing and certification labor

For accurate plumbing takeoffs with full fixture and pipe quantification, contact F&K Estimatings. Our MEP division provides comprehensive Division 22 estimates.