What Is a Plumbing Fixture Schedule?
A plumbing fixture schedule is the table on a drawing set that lists every plumbing fixture on the project by mark, with the manufacturer basis of design, rough-in dimensions, supply and waste connection sizes, and required trim.
It does the same job as a mechanical equipment schedule and carries the same blind spot: it tells you precisely what P-1 has to be, and nothing at all about how many P-1s are in the building.
What's in one
Fixture schedules live on the plumbing sheets, usually P-501 or similar, and are organised by fixture type. Common columns:
Mark. P-1, WC-1, L-1, S-1, FD-1, HB-1. Conventions vary — some engineers number everything sequentially as P-1 through P-14, others use type prefixes. Worth establishing which you're looking at before you count anything.
Description. Water closet, lavatory, urinal, service sink, mop basin, floor drain, floor sink, hose bibb, wall hydrant, trap primer, water hammer arrestor.
Basis of design. Manufacturer and model. American Standard, Kohler, Toto, Zurn, Sloan, Elkay, Just, Fiat. The fixture itself and its trim are frequently different manufacturers on the same line.
Rough-in dimensions. Centreline heights and offsets. This is what the installer sets before the wall closes, and getting it wrong is expensive in a way that a wrong faucet finish isn't.
Supply. Cold and hot connection sizes, usually 1/2" or 3/4".
Waste and vent. Drain and vent sizes — 1-1/4" for a lavatory, 3" or 4" for a water closet.
Carrier. For wall-hung fixtures. Often a separate line item and a meaningful cost.
Trim and accessories. Flush valve, faucet, supplies and stops, P-trap, drain, seat. On a commercial job the trim frequently costs more than the fixture.
Remarks. ADA compliance, sensor operation, vandal-resistant hardware, specific finishes.
What makes it different from an equipment schedule
Three things, and they all affect how you quote it.
The trim is a separate purchase. A mechanical schedule row for RTU-1 describes one thing you buy. A fixture schedule row for a water closet may be a bowl from one manufacturer, a flush valve from another, a carrier from a third, and a seat from a fourth. One row, four line items, potentially three suppliers.
Fixture units drive the system. Each fixture carries a water supply fixture unit and drainage fixture unit value, and those aggregate to size the mains and the drainage stacks. That's an engineering calculation rather than a quoting concern — but it means the fixture schedule is load-bearing on the rest of the design, and a substitution that changes fixture unit values has consequences beyond price.
The vertical system lives elsewhere. Mechanical equipment sits where it's drawn. Plumbing fixtures connect into stacks and vents that run through the building, and that arrangement appears on a riser diagram rather than the floor plan. The fixture schedule tells you nothing about it.
What the schedule won't tell you
Same blind spot as every other schedule, with plumbing-specific wrinkles.
The count is on the plans. A schedule with fourteen rows routinely represents two hundred fixtures. WC-1 appears in every washroom on every floor. The rows describe types; the tagged instances on the floor plans are the quantity.
Repeated washroom layouts. One washroom is drawn in detail and noted typical, or a single plan serves floors two through eight. The multiplier is in a note, not a column — the same trap as multi-residential suite counting.
Fixtures that aren't in the schedule. Floor drains, cleanouts, hose bibbs and trap primers are often shown on plans with a symbol and no schedule row, or scheduled separately in a specialties table. Counting only what's scheduled misses them.
Owner-furnished fixtures. Appliance connections, specialty medical or lab fixtures, and food service equipment are frequently OFCI or NIC. They appear on the plans and are not your scope. The language in the remarks column decides.
Mixed-use buildings. A residential tower with commercial at grade runs two entirely different fixture standards in one set. The schedule may or may not separate them clearly.
Reading one well
Establish the mark convention before counting. Sequential or type-prefixed changes how you tally.
Read the trim column carefully. It is frequently the larger share of the cost, and it varies row to row.
Check what's scheduled against what's on the plans. Symbols without schedule rows are the gap worth chasing.
Find the typicals — repeated washrooms, repeated floors — and expand them before you count anything.
Confirm scope on anything marked OFCI, NIC or by others.
Cross-reference the specification. Division 22 governs acceptable manufacturers and whether a substitution is permitted at all.
On that last point, see basis of design and or-equal.
Where the time goes
Fixture counts are high-volume, repetitive, and spread across every floor plan in the set. A hospital or a school runs into hundreds of tagged fixtures, and the count has to be right before a single price is entered — because on a fixture package, quantity carries the quote the same way it does on grilles and diffusers.
HyperQuote reads the fixture schedule, locates the tagged instances across the plans, deduplicates fixtures appearing on more than one sheet, and produces a bill of materials with the drawing crop behind each count. Plumbing and HVAC/R sets both.
The judgment stays yours — whether a symbol without a schedule row is in scope, whether a typical note covers a whole floor, whether an OFCI fixture is really someone else's. The tallying doesn't.
