77 Ill. Adm. Code 890.420
Pipe Cleanouts
Section 890.420Â Pipe
Cleanouts
a)Â Â Â Â Â Â Â Â Location of Cleanouts Within a Building Drain
1)Â Â Â Â Â Â Â Â Cleanouts shall be not more than 50 feet apart, including the
developed length of the cleanout pipe, in horizontal drainage lines of 4 inches
or less size. Cleanouts shall be not more than 100 feet apart, including the
developed length of the cleanout pipe, in horizontal drainage lines of over 4 inches
to 10 inches in size. Cleanouts shall not be more than 150 feet apart,
including the developed length of the cleanout pipe, in horizontal drainage
lines exceeding 10 inches in size. For underground drainage lines exceeding 10
inches in size, manholes instead of cleanouts shall be provided and shall be
located at intervals of not more than 150 feet.
2)Â Â Â Â Â Â Â Â When it is necessary to conceal a cleanout plug, a readily
accessible covering plate or access door shall be provided.
3)Â Â Â Â Â Â Â Â A test tee at the base of the stack may be used as a cleanout.
4)Â Â Â Â Â Â Â Â A full size cleanout shall be located within 5 feet of the
building foundation, inside or outside, in direct line with the building drain
and sewer.
5)Â Â Â Â Â Â Â Â All cleanouts in vertical stacks shall be located no higher
than 48 inches above the floor.
b)        Change of Direction. A cleanout or manhole shall be installed
at each change of direction of the horizontal building drainage system greater
than 60 degrees; the total of the fittings between cleanouts or manholes shall
not exceed 120 degrees. A manhole within a building shall be provided with an
iron cover which shall be securely bolted in place and made gas and water-tight
with a soft metallic gasket.
c)        Underground Drainage. When installed on an underground drain,
cleanouts shall be extended to or above the finished grade level; or may be
extended to outside of the building. (See Appendix D: Illustration F.)
d)        Concealed Piping. Cleanouts on concealed piping shall be
extended through and terminate flush with the finished wall or floor; or pits
or chases may be left in the wall or floor, provided they are of sufficient size
to permit removal of the cleanout plug and cleaning of the system. (See
Appendix D:Â Illustration G.)
e)        Base of Stacks. A cleanout shall be provided at, or no more
than 4 feet above, the base of each vertical waste or soil stack.
f)        Buildings with Slab Floors. For buildings with a slab floor
or with less than a 36 inch crawl space under the floor, or where a stack
cleanout is not otherwise readily accessible, one of the following shall be
provided in lieu of a cleanout at the base of the stack:
1)Â Â Â Â Â Â Â Â The building drain shall be extended to the outside of the
building and terminated in an accessible cleanout.
2)Â Â Â Â Â Â Â Â An accessible 2 way cleanout shall be installed in the
building drain downstream from the stack provided that no other drainage pipe
connects to such pipe inside the walls of the building unless it has its own
cleanout at the base of the stack or extended outside the building.
g)        Direction of Flow. Every cleanout shall be installed so that
the cleanout opens in a direction opposite to the flow of the drainage line or
at right angles thereto, except as permitted in subsection (f) of this Section.
h)        Cleanout Plugs. A cleanout shall not have a plumbing fixture
installed in it or be used as a floor drain.
i)Â Â Â Â Â Â Â Â Â Cleanouts shall be of the same size as the pipe they serve up
to a maximum of 6 inches, and at least 6 inches for larger pipe.
j)         Cleanout Clearance. All cleanouts shall have a clearance of
18 inches for the purpose of rodding. (See Appendix D: Illustration H.)