Types

• Backflow Preventers
  Air gaps, vacuum breakers, double check, and reduced pressure assemblies that keep contaminated water from flowing back into potable water systems.
• Domestic Water Piping
  Copper, PEX, CPVC, and polypropylene piping that distributes cold and hot potable water from the service to fixtures and equipment.
• Drinking Fountains and Bottle Fillers
  Wall-mounted and freestanding drinking fountains, electric water coolers, and bottle filling stations, with high-low units for accessibility.
• Floor Drains and Cleanouts
  Floor drains, floor sinks, trench drains, and cleanouts that collect floor water and give access for clearing drainage piping.
• Grease Interceptors
  Hydromechanical, gravity, and automatic devices that separate fats, oils, and grease from commercial kitchen waste before it reaches the sewer.
• Lavatories and Sinks
  Hand-washing lavatories and kitchen, service, and utility sinks with faucets, in vitreous china, stainless steel, enameled cast iron, or solid surface.
• Sanitary and Vent Piping
  Drain, waste, and vent piping in cast iron, PVC, or ABS that carries wastewater by gravity to the sewer and vents sewer gases.
• Sanitary Sewer Connections
  The sewer lateral, cleanout, and connection to the public sanitary main, with slope and cover examples, and relocation and abandonment issues.
• Showers and Tubs
  Prefabricated and site-built shower compartments and bathtubs, with pressure-balancing valves, pan liners, and accessible transfer and roll-in types.
• Water Closets and Urinals
  Floor-mounted and wall-hung toilets and urinals with tank or flushometer valves, sized by fixture counts and laid out with code and accessibility clearances.
• Water Heaters
  Storage-tank, tankless, and heat pump water heaters fired by gas or electricity that supply domestic hot water to fixtures and appliances.
• Water Service and Meters
  The water main tap, service line, curb stop, and meter that bring public water to a building, with ownership splits and relocation issues.

Code reference

Always verify the adopted code edition and local amendments for the project jurisdiction.

Governing editions

Fixture counts and toilet facilities

• IPC 2024, Table 403.1: minimum fixtures by occupancy; for example, business occupancies need water closets at 1 per 25 for the first 50 and 1 per 50 for the remainder, lavatories at 1 per 40 for the first 80 and 1 per 80 for the remainder, and one service sink (water closets and urinals, lavatories and sinks, drinking fountains and bottle fillers)
• IPC 2024, Section 403.1.1: occupant load divided equally between sexes and fractions rounded up; all-gender multiple-user facilities calculated on 100 percent of the occupant load
• IPC 2024, Section 403.1.2: single-user and family or assisted-use rooms count toward required fixtures and are identified for use by all persons
• IPC 2024, Section 403.2: separate facilities by sex except in dwelling units, spaces with 15 or fewer occupants, mercantile with 100 or fewer, business with 25 or fewer, and all-person facilities meeting 403.1.2 or 405.3.4 and 405.3.5
• IPC 2024, Section 403.3.3: public and employee facilities no more than one story above or below the space served, with travel distance 500 ft maximum (300 ft in malls)
• IPC 2024, Section 424.2: urinals may replace up to 67 percent of required water closets in assembly and educational occupancies and up to 50 percent in others (water closets and urinals)

Fixture installation

• IPC 2024, Section 405.3.1: fixtures 15 in. minimum from center to side walls or partitions, 30 in. center to center, 21 in. clear in front; compartments 30 in. by 60 in. (floor-mounted) or 30 in. by 56 in. (wall-hung) (water closets and urinals, lavatories and sinks)
• IPC 2024, Section 405.3.4: each public or employee water closet in a compartment with walls and a door, with exceptions for single-occupant rooms (water closets and urinals)
• IPC 2024, Section 405.3.5: urinal partitions 30 in. apart minimum, from 12 in. or less above the floor to at least 60 in., projecting 18 in. from the wall or 6 in. beyond the urinal lip (water closets and urinals)
• IPC 2024, Sections 425.2 and 425.3: elongated bowls and open-front seats in public and employee facilities (water closets and urinals)
• IPC 2024, Section 410: drinking fountains not required for 15 or fewer occupants; at least two (wheelchair and standing) where required; water dispensers may replace up to 50 percent where three or more are required; none in public restrooms (drinking fountains and bottle fillers)
• IPC 2024, Section 413: floor drains per ASME A112.3.1, ASME A112.6.3, or CSA B79, with removable strainers and outlets 2 in. minimum (3 in. in laundries) (floor drains and cleanouts)
• IPC 2024, Section 421: showers at least 900 sq in. with a 30 in. least dimension; walls waterproof to 72 in. above the floor; pan liners turned up 2 in. above the threshold and sloped 1/4 in. per ft (showers and tubs)
• IPC 2024, Sections 412.3 and 412.5: shower and bathtub valves limited to 120°F (showers and tubs)
• IPC 2024, Section 419.5: tempered water at public lavatories through ASSE 1070 devices (lavatories and sinks)

Water supply

• IPC 2024, Table 604.4: maximum flow: private lavatory and sink faucets 2.2 gpm; public lavatory 0.5 gpm or 0.25 gallon per metering cycle; showerheads 2.0 gpm; urinals 1.0 gallon per flush; water closets 1.6 gallons per flush (all fixtures)
• IPC 2024, Section 604.8: pressure-reducing valve where static pressure exceeds 80 psi (domestic water piping)
• IPC 2024, Section 605.2.1: drinking water components meet NSF 372, 0.25 percent weighted average lead (domestic water piping, drinking fountains and bottle fillers)
• IPC 2024, Tables 605.3 and 605.4: water service and distribution pipe materials, including PEX, CPVC, copper, PP, and PE-RT (domestic water piping)
• IPC 2024, Section 607.1.2: tempered water limited to 110°F by ASSE 1070 devices, ASSE 1017 valves, or listed water heaters (water heaters, lavatories and sinks)
• IPC 2024, Section 607.2: hot water piping 50 ft maximum from source to fixture; commercial buildings follow IECC 2024 Section C404.5 (water heaters, domestic water piping)

Water heaters

• IPC 2024, Section 501.6: tankless heater outlet 140°F maximum for domestic use (water heaters)
• IPC 2024, Section 502.3: attic water heaters need a passage 30 in. high by 22 in. wide, 20 ft maximum length, and 30 by 30 in. service space (water heaters)
• IPC 2024, Sections 504.4 to 504.6: relief valves per ANSI Z21.22, set at 210°F and 150 psi or rated pressure maximum; discharge piping full size, by gravity, ending 6 in. maximum above the floor or receptor (water heaters)
• IPC 2024, Section 504.7: drain pans at least 1-1/2 in. deep with a 3/4 in. drain where leakage could cause damage (water heaters)

Backflow protection

• IPC 2024, Table 608.1: backflow devices and standards by degree of hazard, including RPZ (ASSE 1013), double check (ASSE 1015), pressure vacuum breaker (ASSE 1020), and air gap (ASME A112.1.2) (backflow preventers)
• IPC 2024, Section 608.17: protection of specific connections: boilers, heat exchangers, fire sprinkler systems, lawn irrigation, and beverage dispensers (backflow preventers)
• IPC 2024, Section 312.11: testable backflow assemblies inspected and tested at installation, after repair or relocation, and at least annually (backflow preventers)

Drainage and venting

• IPC 2024, Table 704.1: minimum drainage slope 1/4 in. per ft for 2-1/2 in. and smaller, 1/8 in. per ft for 3 to 6 in., 1/16 in. per ft for 8 in. and larger (sanitary and vent piping)
• IPC 2024, Table 709.1: drainage fixture unit values (sanitary and vent piping)
• IPC 2024, Section 708: cleanouts at 100 ft maximum spacing, at horizontal changes over 45 degrees, and at or within 10 ft upstream of the building drain and sewer junction; clearance 18 in. (6 in. and smaller pipe) or 36 in. (8 in. and larger); not concealed (floor drains and cleanouts)
• IPC 2024, Section 306.2.4: tracer wire (14 AWG minimum insulated copper) for buried plastic sewer pipe (sanitary and vent piping)
• IPC 2024, Sections 312.2 and 312.3: drainage tests with 10 ft of water head or 5 psi air (no air test for plastic) for 15 minutes (sanitary and vent piping)
• IPC 2024, Section 903.5: vent terminals not within 10 ft horizontally of doors, operable windows, or intakes unless 3 ft above them (sanitary and vent piping)
• IPC 2024, Section 918.1: air admittance valves per ASSE 1050 (stack) or ASSE 1051 (individual and branch) (sanitary and vent piping)

Traps and interceptors

• IPC 2024, Section 1002.4: trap seals 2 in. to 4 in.; trap seal protection by ASSE 1018 or ASSE 1044 primers, ASSE 1072 barrier devices, or fixture drain connections (floor drains and cleanouts)
• IPC 2024, Section 1003.3: grease interceptors or automatic grease removal devices for food service fixtures; no food waste disposers to interceptors; no emulsifier or enzyme dispensing; dwelling units exempt (grease interceptors)
• IPC 2024, Section 1003.3.5: hydromechanical interceptors per ASME A112.14.3, ASME A112.14.4, CSA B481, or PDI G101, with Table 1003.3.5.1 grease retention capacity by flow rate (grease interceptors)
• IPC 2024, Section 1003.3.7: gravity interceptors per IAPMO/ANSI Z1001, sized at peak drain flow times 30 minutes retention (grease interceptors)

Accessibility

• 2010 ADA Standards, Section 602: drinking fountain spouts 36 in. maximum (wheelchair) and 38 in. to 43 in. (standing) (drinking fountains and bottle fillers)
• 2010 ADA Standards, Section 604: water closets 16 to 18 in. from the side wall, seats 17 to 19 in., wheelchair compartments 60 in. wide by 56 in. (wall-hung) or 59 in. (floor-mounted) deep, ambulatory compartments 35 to 37 in. wide (water closets and urinals)
• 2010 ADA Standards, Section 605: urinal rims 17 in. maximum above the floor (water closets and urinals)
• 2010 ADA Standards, Section 606: lavatory and sink rims 34 in. maximum, forward approach with knee and toe clearance, pipes insulated (lavatories and sinks)
• 2010 ADA Standards, Section 608: transfer showers 36 by 36 in., roll-in 30 by 60 in. or 36 by 60 in., hand shower hose 59 in., water 120°F maximum, thresholds 1/2 in. (showers and tubs)

Referenced standards

Sources

• UpCodes: 2024 IPC Chapter 3 general regulations (GSA adoption without amendments), https://up.codes/viewer/general-services-administration/ipc-2024/chapter/3/general-regulations
• UpCodes: 2024 IPC Chapter 4 fixtures, faucets, and fixture fittings, https://up.codes/viewer/general-services-administration/ipc-2024/chapter/4/fixtures-faucets-and-fixture-fittings
• UpCodes: 2024 IPC Chapter 5 water heaters, https://up.codes/viewer/general-services-administration/ipc-2024/chapter/5/water-heaters
• UpCodes: 2024 IPC Chapter 6 water supply and distribution, https://up.codes/viewer/general-services-administration/ipc-2024/chapter/6/water-supply-and-distribution
• UpCodes: 2024 IPC Chapter 7 sanitary drainage, https://up.codes/viewer/general-services-administration/ipc-2024/chapter/7/sanitary-drainage
• UpCodes: 2024 IPC Chapter 9 vents, https://up.codes/viewer/general-services-administration/ipc-2024/chapter/9/vents
• UpCodes: 2024 IPC Chapter 10 traps, interceptors, and separators, https://up.codes/viewer/general-services-administration/ipc-2024/chapter/10/traps-interceptors-and-separators
• Corada: 2010 ADA Standards Sections 602 to 608, https://www.corada.com/documents/2010ADAStandards/604