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§ 18-29-912.3 — Size

Municipal Code of Chicago (2026 S-74, current through Council Journal of June 17, 2026) · Municipal Code of Chicago § 18-29-912.3

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18-29-912.3 Size.

The minimum size of a combination drain and vent pipe shall be in accordance with Table 18-29-912.3. Table 18-29-912.3 Size of Combination Drain and Vent Pipe (for Floor Drains Only) Diameter Pipe (inches) | Maximum Number of Drainage Fixture Units Connecting to a horizontal branch or stack | Connecting to a building drain or building subdrain Diameter Pipe (inches) | Maximum Number of Drainage Fixture Units Connecting to a horizontal branch or stack | Connecting to a building drain or building subdrain 2 | 3 | 4 2 1/2 | 6 | 26 3 | 12 | 31 4 | 20 | 50 5 | 160 | 250 6 | 360 | 575 For SI: 1 inch = 25.4 mm.