1 Scope
NOTE This standard covers the manufactured drainage specialties that terminate the sanitary waste-and-vent system at a usable drainage point: floor drains, area drains, cleanouts, fixture carriers, trap primers, trap-seal protection devices, backwater valves, hub and drum traps, and the strainers, sediment buckets, extension necks, and clamping collars that complete those assemblies. (1.1)
NOTE These specialties are the interface between the buried or concealed drainage piping and the occupied space; their selection drives floor construction coordination, trap-seal maintenance, sewer-gas exclusion, and accessible-fixture support, which is why they are specified separately from the piping that conveys the waste. (1.2)
1.3All specialties furnished under this standard shall be listed to the applicable ASME A112 product standard for the device type and shall be compatible with the connected pipe material and joint system.
1.4Devices and connections shall comply with the plumbing code adopted by the authority having jurisdiction, which in most US jurisdictions is the International Plumbing Code (IPC) or the Uniform Plumbing Code (UPC).
NOTE The following are outside scope: (1.5)
- Waste-and-vent pipe, fittings, hangers, and venting — see Sanitary Waste And Vent Piping
- Trench drains, channel drains, slot drains, and grease and oil interceptors — see Trench Drains And Interceptors
- Plumbing fixtures proper (water closets, urinals, lavatories, sinks, tubs) and their trim and supply — see Plumbing Specialties; the fixture carrier in this standard supports the fixture but does not include the fixture
- Domestic water specialties (backflow preventers, pressure-reducing valves, water hammer arresters) — see Domestic Water Piping Specialties; only the cold-water supply branch serving a trap primer is coordinated here
- HVAC condensate drainage piping and trap primers serving HVAC equipment — see Condensate Drainage Piping
- Roof drains, overflow drains, and stormwater collection (storm-drainage scope), even though roof drains share the ASME A112 product family
2 Referenced Standards
2.1Equipment, materials, and installation shall comply with the latest adopted edition of each of the following unless a specific edition is cited.
2.2Where referenced standards conflict, the more stringent requirement shall govern unless the Engineer of Record directs otherwise in writing.
| Standard |
Title |
| ASME A112.6.3 / CSA B79.3 |
Floor and Trench Drains (floor and area drain product standard) |
| ASME A112.36.2M / CSA B79.2 |
Cleanouts |
| ASME A112.6.1M |
Supports for Off-the-Floor Plumbing Fixtures for Public Use |
| ASME A112.6.2 |
Framing-Affixed Supports for Off-the-Floor Water Closets with Concealed Tanks |
| ASME A112.14.1 / CSA B181.1 |
Backwater Valves |
| ASME A112.21.2M |
Roof Drains (referenced for boundary differentiation only) |
| ASME A112.6.9 |
Siphonic Roof Drainage Systems (referenced for boundary differentiation only) |
| PDI WH-201 |
Water Hammer Arresters (trap-primer supply sizing reference) |
| IAPMO/ANSI Z1001 |
Prefabricated Plumbing Units |
| ASTM A74 |
Cast Iron Soil Pipe and Fittings |
| ASTM A888 |
Hubless Cast Iron Soil Pipe and Fittings for Sanitary and Storm Drain, Waste, and Vent Piping Applications |
| ASTM A48 |
Gray Iron Castings |
| ASTM A536 |
Ductile Iron Castings |
| NSF/ANSI 14 |
Plastics Piping System Components and Related Materials |
| NSF/ANSI 2 |
Food Equipment |
| IPC |
International Plumbing Code, Chapter 7 (Sanitary Drainage) and §405 (carriers) |
| UPC |
Uniform Plumbing Code, Chapter 7 (Sanitary Drainage) |
3 Submittals
3.1 Action Submittals
3.1.1The Contractor shall submit the following action submittals for review before fabrication or delivery:
- Product data for each floor drain, area drain, cleanout, fixture carrier, trap primer, trap-seal device, and backwater valve, identifying body material, outlet size and configuration, grate or cover material and finish, and load rating.
- Shop drawings showing carrier type, leg-height adjustment range, anchorage, and bearing-plate details for each fixture support, coordinated with the fixture rough-in dimension.
- A drainage-specialty schedule keyed to the drawings listing each mark, its location, invert or floor elevation, and the connected pipe size and material.
- Manufacturer's selection data demonstrating grate open area and load class for each drain in its service condition.
- Trap-primer supply schematic showing the cold-water source, primer location, and the drains served by each primer.
☑ Product data for drains, cleanouts, carriers, primers, and valves
☑ Carrier shop drawings with leg-height and anchorage details
☑ Drainage-specialty schedule keyed to drawings
☐ Grate open-area and load-class selection data
☑ Trap-primer supply schematic
3.2 Closeout Submittals
3.2.1The Contractor shall submit the following closeout submittals before Substantial Completion:
- Operation and maintenance data covering trap-primer adjustment, sediment-bucket cleaning intervals, backwater-valve inspection, and trap-seal device replacement.
- Record documents marking the as-built location of every cleanout, backwater valve, and concealed carrier.
- Manufacturer warranty documentation for each specialty.
☑ O&M data (primer, sediment bucket, backwater valve, trap-seal device)
☑ Record documents locating cleanouts, backwater valves, and carriers
☑ Manufacturer warranty documentation
3.3.1The Contractor shall submit the following informational submittals:
- Certification that each device is listed to the applicable ASME A112 product standard.
- Certification that drains and carriers in food-service areas comply with NSF/ANSI 2.
- Field test reports for the hydrostatic or pneumatic test of the installed drainage specialties.
☑ ASME A112 listing certification
☐ NSF/ANSI 2 certification for food-service areas
☑ Field test reports
4 Quality Assurance
NOTE Each drainage specialty shall be the product of a single manufacturer for each device type, so that grates, extension necks, and accessories are interchangeable and the warranty is undivided. (4.1)
4.2Floor and area drains shall be listed to ASME A112.6.3 / CSA B79.3.
4.3Cleanouts shall be listed to ASME A112.36.2M / CSA B79.2.
4.4Fixture carriers shall be listed to ASME A112.6.1M, and concealed-tank carriers for wall-hung water closets shall additionally comply with ASME A112.6.2 as referenced by the adopted plumbing code.
4.5Backwater valves shall be listed to ASME A112.14.1 / CSA B181.1.
4.6Drains, carriers, and cleanouts installed in commercial kitchens, food-preparation areas, and other food-service spaces shall be stainless steel.
4.7Drains, carriers, and cleanouts in food-service spaces shall comply with NSF/ANSI 2.
4.8The installer shall be experienced in plumbing-specialty installation and shall set carriers and drains to the tolerances required by the connected fixture and floor assembly.
5 Environmental and Service Conditions
NOTE The service condition — frequency of use, presence of a waterproof membrane, traffic load, and corrosive or sanitary environment — governs the body material, grate class, trap type, and trap-seal protection of every drain. Selecting a drain on outlet size alone, without these conditions, is the most common source of field failure. (5.1)
5.2Floor drains in intermittently used spaces — mechanical rooms, janitor closets, stair towers, and seasonal areas — shall be provided with trap-seal protection so the seal does not evaporate and admit sewer gas.
5.3Drains and grates in vehicular areas — parking garages, loading docks, and service drives — shall be rated for the wheel load of the heaviest anticipated vehicle.
5.4Drains and carriers in coastal, high-chloride, or pharmaceutical environments shall use Type 316 stainless steel where stainless steel is specified.
NOTE The trap seal of an unused floor drain evaporates over weeks to months depending on humidity and temperature; once the seal is lost, the drain becomes an open path for sewer gas, which is both a nuisance and a code violation under IPC §1002.4. Trap primers and trap-seal inserts exist specifically to prevent this. (5.4.1)
6 Floor and Area Drains
6.1 Body Material and Construction
NOTE Floor drain bodies are most commonly cast iron for general commercial service, stainless steel where sanitation or corrosion resistance governs, and PVC or ABS only in residential and light-commercial work. Cast iron is the 80% default because of its durability, weight, and broad availability. (6.1.1)
6.1.2Floor drain bodies shall be cast iron conforming to ASTM A74 or ASTM A888 unless another material is scheduled for the service condition.
6.1.3Stainless-steel drain bodies, where specified, shall be Type 304 minimum, and Type 316 in coastal, high-chloride, or pharmaceutical environments.
6.1.4Plastic drain bodies, where permitted, shall conform to NSF/ANSI 14 and shall not be used in commercial kitchens or food-service areas.
6.1.5Each drain body shall have a coated or factory-finished interior appropriate to the connected pipe and the conveyed effluent.
● Cast iron (ASTM A74 / A888) - standard commercial
○ Stainless steel Type 304 - food service / healthcare
○ Stainless steel Type 316 - high-chloride / pharmaceutical
○ PVC or ABS (NSF/ANSI 14) - residential / light commercial
6.1.6The drain outlet configuration shall match the connected piping joint system and routing.
Bottom outlet, no-hub
Bottom outlet, hub-and-spigot
Bottom outlet, threaded
Side outlet, no-hub
Side outlet, hub-and-spigot
NOTE The drain outlet size shall be sized for the drainage fixture-unit load but shall not be smaller than 2 in. (50 mm). (6.1.7)
6.2 Trap and Seal
NOTE Every floor drain shall be trapped, either with an integral P-trap cast into the drain body or with a separate P-trap installed immediately below the drain. (6.2.1)
6.2.2Each floor drain shall be provided with a trap, integral or separate, maintaining a liquid seal of not less than 2 in. (50 mm).
6.2.3Floor drains in infrequently used spaces, or where evaporation is a concern, shall be provided with a deep-seal trap maintaining not less than 4 in. (100 mm) of liquid seal, or with a trap-seal protection device.
6.2.4Combination floor drain and cleanout assemblies shall provide a removable plug giving rodding access to the trap and outlet without removing the drain body.
● Integral P-trap, standard 2 in. (50 mm) seal
○ Integral P-trap, deep seal 4 in. (100 mm)
○ Separate P-trap below drain
○ Combination drain and cleanout with integral trap
6.3 Grate and Strainer
NOTE The grate is selected for two independent properties — material and finish for the architectural setting, and load class for the traffic over it. The two are chosen separately; a heavy-duty load class does not imply a particular finish. (6.3.1)
6.3.2Each floor drain shall be provided with a grate or strainer with a free open area not less than the area required by ASME A112.6.3 for the drain size.
6.3.3Grates in accessible routes shall be heel-proof, with openings not exceeding the dimension permitted for the accessible path of travel.
6.3.4The grate material and finish shall be as scheduled for the architectural setting.
Cast iron
Ductile iron
Nickel bronze
Polished stainless steel
Vandal-resistant secured grate
NOTE Grates shall be rated for the load class of the traffic passing over them. A pedestrian or light-duty grate installed in a vehicular area will fail under wheel load; vehicular areas require a heavy-duty (H-20) grate. (6.3.5)
6.3.6Grates in vehicular and forklift areas shall be heavy-duty load class rated for the design wheel load.
● Light duty (pedestrian)
○ Medium duty
○ Heavy duty (H-20, vehicular)
6.3.7Floor drains in mechanical rooms, equipment rooms, and food-service areas shall be provided with a removable sediment bucket to intercept debris before it enters the building drain.
○ Removable sediment bucket required
● Open grate, no bucket
6.4 Adjustability and Membrane Flashing
NOTE Drain body height must match the finished floor assembly. Where the slab thickness varies, or where tile is set over a waterproof membrane, an adjustable collar or extension neck is required so the grate finishes flush; a fixed-flange drain set before the floor assembly is confirmed will finish high or low. (6.4.1)
6.4.2Floor drains in slabs of varying thickness, or set before the finished floor assembly is confirmed, shall be the adjustable-collar or extension-neck type so the grate finishes flush with the finished floor.
6.4.3Floor drains installed in waterproofed slabs — tiled shower bases, locker-room floors, planters, and parking decks — shall be provided with a clamping collar and membrane flashing ring to bond the waterproof membrane to the drain body.
6.4.4The clamping collar shall be cast iron or Type 304 stainless steel with a bolted clamping ring engaging the membrane on all sides.
○ Fixed flange (confirmed slab thickness)
● Adjustable collar / extension neck
○ Required (waterproofed slab)
● Not required (no membrane)
7 Cleanouts
NOTE Cleanouts give rodding access to the drainage piping for clearing blockages. Their type follows the access surface — in the pipe line, in the floor, in a wall, or at grade — and their spacing and clearance are fixed by the plumbing code, not by the designer's preference. (7.1)
7.2Cleanouts shall be provided at the spacing and locations required by the adopted plumbing code, including at each aggregate change of direction exceeding 135 degrees and at the intervals set by IPC §708 for the building drain and horizontal branches.
7.3Each cleanout shall provide a full-size opening not smaller than the pipe it serves, up to the maximum cleanout size required by code.
7.4Cleanouts shall be installed with the rodding clearance required by code — not less than 18 in. (457 mm) for piping 6 in. and smaller, and not less than 36 in. (914 mm) for piping 8 in. and larger.
NOTE Cleanout access frames and covers embedded in architectural finishes are part of the plumbing contractor's scope; their coordination with the finish contractor is the plumbing contractor's responsibility. (7.5)
7.6Cleanout access frames and covers shall be furnished by the plumbing contractor and coordinated with the finish contractor before finishes are applied.
7.7Cleanout access frames and covers shall not be left to the finish trade to furnish or locate.
7.7.1The cleanout type shall match the access surface and traffic condition.
In-line (within pipe diameter)
Floor access, round frame and cover
Floor access, square frame and cover
Wall access, round cover
Wall access, rectangular cover
Grade-level, traffic-rated (H-20)
7.7.2Floor cleanouts in vehicular areas shall have a traffic-rated (H-20) frame and cover.
● Non-traffic (pedestrian)
○ Traffic-rated (H-20)
7.7.3The cleanout plug material shall be compatible with the connected pipe.
NOTE Wall cleanout access covers in finished walls shall be the finish scheduled for the wall, and their locations shall be coordinated with the architectural finish drawings. (7.7.4)
7.7.5Wall cleanout covers in tiled or finished walls shall be furnished with a frame matching the finish material and shall be located as coordinated with the architectural drawings. wall cleanout locations in finished walls 8 Fixture Carriers
NOTE A fixture carrier is the structural support that transfers the load of a wall-hung water closet or urinal into the floor or wall framing and routes its waste outlet to the drainage piping. The carrier type follows the fixture: floor-mounted Type I carriers support wall-hung water closets; wall-attached Type II carriers support urinals. (8.1)
8.2Carriers for wall-hung water closets shall be floor-mounted Type I supports listed to ASME A112.6.1M.
8.3Carrier legs shall be adjustable and anchored to the structural floor.
8.4Concealed-tank carriers for wall-hung water closets shall comply with ASME A112.6.2 and shall provide the supply inlets required by the connected fixture.
8.5Carriers for urinals shall be wall-attached Type II supports listed to ASME A112.6.1M, with bearing plates and hanger rods anchored to the wall framing.
8.6Exposed steel carriers may be used in mechanical chases where the chase remains unfinished.
8.7Carriers in finished, occupied walls shall be the concealed type.
NOTE The carrier rough-in height shall match the connected fixture's actual rough-in dimension. A carrier set to a different rough-in height than the fixture it supports requires a special offset and is a common field error; the fixture rough-in shall be confirmed before the carrier is ordered. (8.7.1)
8.7.2The carrier outlet centerline height above finished floor shall match the connected fixture rough-in dimension, confirmed against the fixture manufacturer's data before ordering.
● Floor-mounted Type I (wall-hung water closet)
○ Concealed-tank carrier (wall-hung water closet)
○ Wall-attached Type II (urinal)
NOTE Carrier load rating follows the room: standard fixture support carries the code-minimum load, but an accessible water closet must use a heavy-duty carrier rated for the accessible-fixture load. Specifying a standard carrier in an accessible toilet room is a code compliance failure. (8.7.3)
8.7.4Standard fixture carriers shall be rated for not less than 500 lb (227 kg) of vertical load at the fixture.
8.7.5Carriers supporting water closets in accessible toilet rooms shall be heavy-duty, rated for not less than 1,000 lb (454 kg) of vertical load at the fixture.
● Standard 500 lb (227 kg)
○ Heavy-duty / bariatric 1,000 lb (454 kg)
9 Trap Primers and Trap-Seal Protection
NOTE A trap that is not regularly refilled will lose its seal to evaporation. Trap-seal protection replenishes or replaces that seal by one of two strategies: a water-supply trap primer that periodically adds water to the trap, or a trap-seal insert that mechanically blocks sewer gas without relying on a water seal. The choice turns on water availability and maintenance philosophy. (9.1)
9.2Floor drains and other traps in intermittently used locations shall be protected against trap-seal loss by a trap primer or a trap-seal protection device.
9.3 Trap-Seal Protection Method
NOTE Water-supply trap primers add a metered charge of cold water to the trap on a pressure-differential or timed cycle; trap-seal inserts (trap-guard type) are check devices installed in the trap that close against sewer gas and require no water supply. Inserts are favored on water-conservation and green projects because they eliminate a continuous water draw. (9.3.1)
9.3.2Where a water-supply trap primer is used, it shall be a listed pressure-differential or electronic-solenoid primer.
9.3.3Where a trap-seal insert is used, it shall be a listed mechanical trap-seal device suitable for the drain and effluent.
● Automatic pressure-differential water-supply primer
○ Electronic solenoid water-supply primer
○ Mechanical trap-seal insert (no water supply)
9.4 Trap Primer Supply
9.4.1Trap-primer supply shall connect to the domestic cold-water main only.
NOTE A hot-water connection to a trap primer causes thermal expansion problems and defeats the pressure-differential operation of the primer; the cold-water main is the only permissible source. (9.4.2)
9.4.3Water-supply trap primers shall be served from the domestic cold-water system through a connection not smaller than 1/2 in. (15 mm).
9.4.4Trap-primer supply shall not be connected to a hot-water main under any circumstance.
9.4.5Pressure-differential trap primers shall be installed within their operating supply-pressure range of 15 psi to 125 psi (103 kPa to 862 kPa).
9.4.6A single primer serving multiple drains shall distribute the primer charge through a listed distribution unit sized for the number of traps served.
10 Backwater Valves
NOTE A backwater valve is a one-way check device that prevents a surcharged public sewer from backing up into the building. It is required only for fixtures and drains that sit below the elevation of the next upstream manhole rim; installing one on fixtures above that elevation adds cost and creates nuisance blockages without benefit. (10.1)
10.2Backwater valves shall be provided where the connected fixtures or drains are below the elevation of the next upstream manhole rim, as required by the adopted plumbing code (IPC §715 / UPC §719).
10.3Backwater valves shall not be installed to serve fixtures that drain above the upstream manhole rim.
10.4Each backwater valve shall be listed to ASME A112.14.1 / CSA B181.1 and shall provide access for inspection and maintenance of the flapper and seat.
10.5A mainline backwater valve shall be sized to match the building drain it protects, typically 4 in. (100 mm).
10.5.1The backwater valve type shall match the installation.
Normally-open flap, inline
Normally-closed (below-grade fixtures)
Combination cleanout and backwater valve
Mainline backwater valve
10.5.2The backwater valve body and access cover material shall be as scheduled for the installation.
● Cast iron with bronze internals
○ Bronze
○ PVC (NSF/ANSI 14)
11 Hub Drains, Drum Traps, and Accessories
NOTE Hub drains receive indirect waste from equipment by an air gap; drum traps and miscellaneous accessories complete specialized drainage assemblies. These are specified here because they share the same product family and installation trades as floor drains. (11.1)
11.2Hub drains receiving indirect waste shall provide an air gap between the indirect waste pipe and the flood-level rim of the hub as required by code.
11.3Drum traps, where retained on existing systems or required for a specific fixture, shall be provided with a removable cleanout cover giving full access to the trap interior.
11.4Drain accessories — extension necks, clamping collars, sediment buckets, strainer baskets, and grates — shall be the product of the drain manufacturer and shall be interchangeable within the drain series.
11.4.1Strainer baskets and sediment buckets shall be removable for cleaning without disturbing the drain body or the connected piping.
12 Testing
NOTE Installed drainage specialties shall be tested with the drainage system before concealment, so that a leak at a drain, cleanout, or carrier connection is found and corrected before finishes are placed. (12.1)
12.2The drainage system, including the specialties furnished under this standard, shall be hydrostatically tested by filling to the flood-level rim of the highest connected outlet and holding for not less than 15 minutes with no leakage.
12.3Where a hydrostatic test is impractical, a pneumatic test at 5 psi (34.5 kPa) held for not less than 15 minutes with no loss of pressure may be substituted.
12.4Trap primers shall be tested by observing a primer cycle and confirming water delivery to each trap served.
12.5Backwater valves shall be tested by operating the flapper through its full travel and confirming the seat closes.
12.6Defective devices, joints, or connections disclosed by the test shall be repaired or replaced and the test repeated until no leakage occurs.
● Hydrostatic to flood-level rim, 15 min hold
○ Pneumatic 5 psi (34.5 kPa), 15 min hold
13 Installation
NOTE Drainage specialties shall be installed so the connected piping pitch, the finished-floor flush condition, and the code-required access are all achieved together; setting a drain or cleanout to satisfy one of these at the expense of another is not acceptable. (13.1)
13.2Floor drains shall be set so the grate finishes flush with the finished floor and the surrounding floor slopes to the drain.
13.3Cleanouts shall be installed flush with or accessible from the finished surface and shall maintain the rodding clearance required by code.
13.4Fixture carriers shall be anchored to the structure before the wall or floor is closed, and shall be set to the confirmed fixture rough-in height and made plumb and rigid.
13.5Clamping-collar drains at waterproofed slabs shall be installed with the membrane fully engaged and clamped before the topping or tile is placed.
13.6Trap primers and trap-seal devices shall be installed accessible for adjustment, cleaning, and replacement.
13.7Dissimilar-metal connections shall be isolated to prevent galvanic corrosion between the specialty and the connected piping.
14 Delivery, Storage, and Handling
14.1Drainage specialties shall be delivered in the manufacturer's packaging with grates, plugs, and covers protected and identified by mark.
14.2Open drain bodies, cleanout openings, and carrier outlets shall be capped or plugged during construction to keep debris and construction waste out of the drainage system.
14.3Stainless-steel and finished-bronze grates and covers shall be stored to protect their finish from scratching and from corrosive contact with carbon steel.
15 Warranty
15.1The manufacturer shall warrant each drainage specialty against defects in material and workmanship for not less than one year from Substantial Completion.
15.2The installing contractor shall warrant the installation, including leak-free joints and proper carrier anchorage, for not less than one year from Substantial Completion.
16 Spare Parts
16.1The Contractor shall furnish to the Owner the spare grates, strainer baskets, sediment buckets, and trap-seal devices required for routine maintenance.
☐ Spare floor drain grates (one per drain type)
☑ Spare strainer baskets and sediment buckets
☑ Spare trap-seal insert devices
☐ Cleanout plug assortment