10.1 Cleanouts & Manholes (SPS 382.35)

Purpose

Every foot of drain piping must be reachable for rodding. SPS 382.35 sets the maximum distances between access points and how those access points are built.

Where cleanouts are required (SPS 382.35 (3))

Horizontal drains inside or under a building

Building sewers and private interceptor main sewers

Specific locations

• Building drain to building sewer junction: a cleanout within 5 feet of where they connect, inside or outside the building. A stack cleanout can serve if the stack is within 5 feet of the junction.
• Stacks and conductors: where a cleanout is provided in a drain stack or a storm conductor, it must be no more than 60 inches above the lowest floor the stack penetrates.
• Branches serving batteries of fixtures: cleanouts so every part of the branch can be cleaned. Removable fixture traps count. No cleanout is needed for a branch with one floor-outlet fixture and the fixtures draining into its wet vent.
• Greasy wastes: cleanouts no more than 40 feet apart and at every change in direction over 45 degrees.
• Double sanitary tees in vertical drains under 3 inches: a cleanout immediately above or below, unless a stack cleanout is provided.
• Traps: stoppages must be removable from traps and horizontal fixture drains. A non-removable trap without a removable dip needs a cleanout or removable inlet.
• Garage catch basins and interceptors: an accessible cleanout outside the basin, within 15 inches of the trap weir.
• Sampling manholes may be required by municipal ordinance.

Installation (SPS 382.35 (4) and (5))

1. Every cleanout opens in the direction of flow or at a right angle to it.
2. Cleanout plugs may not be covered with cement, plaster or other permanent finish.
3. Underground cleanouts extend vertically to or above finished grade. Where the riser is more than 18 inches above the drain, it connects through a fitting meeting Table 382.30-4 radii.
4. Outside cleanouts get a frost sleeve:
   • Building-sewer material.
   • The bottom ends 6 to 12 inches above the pipe or at least 6 inches below the predicted frost depth.
   • A removable watertight top strong enough for traffic.
   • In vehicle areas, the sleeve top ends in a concrete pad at least 4 inches thick extending 9 inches on all sides and sloping away.
5. In concealed spaces, cleanouts extend to the wall or floor surface or have access panels large enough to remove the plug and rod the pipe.
6. Cleanout openings may not be used to connect fixtures or floor drains unless another cleanout of equal access and capacity is provided.

Cleanout sizes (Table 382.35)

When a nonpublic 6-inch sanitary sewer is repaired or replaced, an existing 4-inch cleanout extension inside the building may be reused.

Manholes (SPS 382.35 (8))

Manholes are at least 42 inches in diameter with an access opening of at least 23 inches, built of approved materials per NR 110.13. The code note summarizes NR 110.13:

• Shaped flow channels.
• Watertight covers where flooding is possible.
• Flexible watertight pipe connections.
• An outside drop where the incoming invert is 2 feet or more above the spring line of the outlet.

Worked example

A 4-inch PVC building sewer runs 260 feet from the building to the street. Option 1: cleanouts at the 5-foot junction cleanout, then at no more than 100-foot intervals, which means cleanouts at about 100 and 200 feet and the final 60 feet ending at the main. Option 2: a manhole partway along. A cleanout may be up to 200 feet downstream of a manhole, and a manhole up to 300 feet downstream of a cleanout.

Each outdoor cleanout needs a frost sleeve. Where the driveway crosses, the sleeve top sits in a 4-inch pad extending 9 inches around it. Each cleanout riser connects to the sewer through a long-radius fitting because it rises more than 18 inches.