Drains & Cleanouts
Drains and cleanouts are the collection and access points of a building drainage system. Drains collect water from floors, equipment, and roofs and channel it into the piping, while cleanouts provide a sealed opening for inspecting and clearing the line. Together, they are core components of a drainage system. This category covers plumbing drainage products for commercial, light commercial, and residential work, including floor, roof, and indirect waste receptors, cleanout bodies, and replacement covers and plugs.
Typical body materials include cast iron, PVC, and ABS, with outlet sizes and connection types matched to the pipe they serve. Use the product groups below to compare drain and cleanout supplies by function, install location, and governing standard before you order for a new build, a tenant improvement, or a repair.
Drains & Cleanouts
Drains & Cleanouts Products
Each group below covers one part of the system, from access fittings to water receptors.
Cleanouts
Cleanouts are fittings installed in drain lines that provide a removable plug or cover for rodding, camera inspection, and line clearing. Cleanouts for plumbing systems install at changes in direction and at the base of stacks. Common types include floor, wall, and in-line test tee cleanouts built to ASME A112.36.2M.
Cleanout Accessories
Cleanout accessories replace or complete an existing access point. Typical items include floor and wall access covers, threaded plugs in brass or cast bronze, and housings that hold the plug at finished floor level. Use them to replace a cracked or missing cover without opening the line.
Floor Drains
Floor drains collect surface water from mechanical rooms, restrooms, and wash-down areas and channel it through a trap into the drain line. Bodies are built for on-grade or above-grade installation, with adjustable strainers that are set flush with the finished floor. Many models include a trap primer connection that protects the trap seal.
Floor Sinks
Floor sinks are recessed receptors designed for indirect waste from ice machines, prep sinks, dishwashers, and condensate lines. The discharge pipe terminates above the rim with an air gap, which prevents backflow. Bodies are typically enamel-coated cast iron or stainless steel and follow ASME A112.6.7.
Roof Drains
Roof drains collect rainwater at low points of flat and low-slope roofs and route it to conductors. Each assembly pairs a body and dome strainer with a flashing clamp that seals to the membrane. Overflow models with a water dam provide secondary drainage. Most follow ASME A112.6.4.
How Drains and Cleanouts Work and Where to Use Them
How Drainage Components Work Together
Water enters the system at a receptor, passes through a trap that holds a water seal against sewer gas, and flows by gravity into branch lines, stacks, and the building drain. Cleanouts sit along this path so a line can be opened and cleared without cutting pipe. Where a floor drain sees little use, a trap primer adds small amounts of water to maintain the seal. Vents protect each trap from siphoning.
Commercial and Light Commercial Applications
Commercial drainage products are specified room by room. Commercial kitchens pair floor sinks for equipment waste with floor drains for wash-down. Restrooms and locker rooms use finished-floor drains and floor cleanouts with nickel bronze or stainless steel tops. Mechanical rooms need drains sized for equipment discharge, while parking areas require heavy-duty grates rated for vehicle loads.
Roof and Storm Drainage
On commercial buildings, roof drains connect to vertical conductors that carry storm water down to the storm line. Set each drain at a roof low point, seal the flashing collar to the membrane, and add test tees or wall cleanouts in the conductors for inspection access.
Key Specifications & Planning Steps
Outlet size: Match the outlet to the connecting pipe. Cleanouts are commonly specified at the same size as the drain line up to 4 in.
Connection type: Choose no hub, hub, threaded, push-on, or solvent weld to suit cast iron, PVC, or ABS piping.
Body and top material: Cast iron bodies suit most commercial work, and plastic bodies suit light commercial and residential lines. Tops come in nickel bronze, stainless steel, or cast iron.
Standards: Floor drain bodies follow ASME A112.6.3, floor sink bodies ASME A112.6.7, roof drain bodies ASME A112.6.4, and cleanouts ASME A112.36.2M.
Testing: Drains, floor sinks, and floor cleanouts installed above grade must be leak tested for watertightness.
Cleanout placement: Common practice places cleanouts at each change in direction greater than 45 degrees, at intervals of no more than 100 feet, and at the base of each stack. Confirm requirements with the local code.
Choosing the Right Drains & Cleanouts
Start with location and load. A finished restroom floor needs an adjustable strainer that sets flush with tile, while a parking deck needs a heavy-duty grate and a body built for vehicle traffic. For equipment waste, choose a floor sink sized to the number of indirect connections, and add a sediment bucket where solids are expected. Place cleanouts where a technician can reach them, and use access covers in finished walls and floors. Match all drains and cleanouts to the pipe material already on site to avoid extra adapters and transition fittings.
Frequently Asked Questions
Where can I buy floor drains, floor sinks, and cleanouts for a commercial plumbing job in one place?
This category groups floor drains, floor sinks, roof drains, cleanouts, and cleanout accessories on one page, so the main receptors and access fittings for a commercial job can be sourced together. Compare each group by outlet size, body material, and connection type to match the project piping.
What drain and cleanout supplies do I need to rough in a restaurant kitchen?
A typical commercial kitchen rough-in uses floor sinks for indirect waste from ice machines, dishwashers, and prep sinks, floor drains for wash-down areas, and cleanouts on branch lines and at the base of stacks. Trap primer connections are often specified for drains that see little use. Confirm the layout against the approved plans and local code.
What is the difference between a floor drain and a floor sink?
A floor drain collects water that spills or is washed across the floor through a strainer or grate. A floor sink is a deeper recessed receptor that accepts indirect waste piped from equipment, with the discharge ending above the rim to form an air gap. Floor drains follow ASME A112.6.3, and floor sinks follow ASME A112.6.7.
Cast iron vs PVC cleanouts: which should I use for a commercial building?
Match the cleanout to the pipe it serves. Cast iron cleanouts suit cast iron drain lines and installations where noncombustible piping is required. PVC and ABS cleanouts suit plastic drain, waste, and vent lines in light commercial and residential work. Check the project specification and local code before ordering.
Should I pick a nickel bronze or stainless steel top for a floor cleanout in a high-traffic area?
Both materials resist corrosion. Nickel bronze tops are widely used in finished commercial floors and hold up to foot traffic and cleaning chemicals. Stainless steel suits food service and wash-down areas. Where carts or vehicles cross the cleanout, choose a top and housing rated for that load.
Where are cleanouts required in a commercial drainage system?
Common practice places cleanouts for plumbing lines at each change in direction greater than 45 degrees, at intervals of no more than 100 feet on horizontal runs, and at the base of each vertical soil and waste stack. Exact requirements depend on the plumbing code adopted locally, so confirm them with the authority having jurisdiction.
How do I stop a floor drain trap from drying out and letting sewer gas into a building?
Keep water in the trap. A trap primer connected to the drain body or trap adds small amounts of water on a schedule or when a nearby fixture is used. Trap seal devices that install inside the drain are another option where code allows them. Drains in regular use stay sealed through normal flow.
What size roof drain do I need for a flat commercial roof?
Roof drain size depends on the roof area served, the local design rainfall rate, and the conductor pipe size. Plumbing codes provide sizing tables based on these values, and the drain outlet is matched to the conductor. Most projects also need an overflow drain or scupper for secondary drainage.
A cleanout cover is cracked in a finished floor. What do I need to replace it?
Measure the cover or opening diameter, note the thread type or screw pattern, and check whether the plug, the housing, or both are damaged. Cleanout accessories such as replacement covers, plugs, and housings restore the access point without cutting into the drain line.
Which floor drains need to be leak tested when they are installed above grade?
Manufacturer guidance states that floor drains, floor sinks, and floor cleanouts installed above grade must be leak tested for watertightness, and that roof drains must be tested according to local codes and standards. Testing confirms the seal between the drain body, the floor membrane, and the connecting pipe.
What are the main components of a drainage system in a commercial building?
The main components of a drainage system are receptors such as floor drains, floor sinks, and roof drains, traps that hold a water seal, branch and stack piping, vents that protect the traps, cleanouts for access, and the building drain that carries waste to the sewer. Storm water from the roof runs through separate conductors.
What ASME standards apply to floor drains, floor sinks, roof drains, and cleanouts?
Floor drains follow ASME A112.6.3, sanitary floor sinks ASME A112.6.7, roof, deck, and balcony drains ASME A112.6.4, and cleanouts ASME A112.36.2M. Product listings may also reference IAPMO or UPC compliance.
What kind of drain goes under an ice machine or a three-compartment sink?
A floor sink is the standard receptor for this equipment. The waste line terminates above the floor sink rim with an air gap, so wastewater cannot back up into the equipment. Some jurisdictions accept an air break for certain fixtures, so check the local plumbing and health codes.
What should I check before ordering plumbing drains and cleanouts for a new building?
Before ordering plumbing drains and cleanouts, confirm outlet size, connection type, body material, top or grate material and load rating, the governing ASME standard, and whether trap primer connections are needed. Also check the cleanout locations on the plans against local code requirements.
Do roof drains need an overflow drain, and how is it different from the primary drain?
Most codes require secondary roof drainage, which is often provided by overflow drains or scuppers. An overflow drain sits beside the primary drain and uses a raised water dam, so it only takes water when the primary drain is blocked or overwhelmed. Secondary roof drains typically discharge through separate piping to a visible point.