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SUBJECT: Shower Control Valves
SECTION: 408.3 (2021 UPC)
Question:
1. Is there a distance or proximity that a shower valve must be from the entrance?
2. Please define “Point of Use.”
Comment: Can you please clarify the intention of section 408.3 “These valves shall be installed at the point of use” We have a large walk-in shower, roughly 10’x 4’. On one end there is an entrance and drying area, and the shower head is on the opposite end. We want to install the valve control by the entrance, as the wall toward the shower head is all glass and so we can turn it on without walking to the head that will be spraying toward us. The inspector is saying that we have to be able to reach the valve while in the shower spray, “the point of use.” We have installed hundreds of these over the years and never had a problem. Your insight and reasoning is appreciated.
Answer:
- No, however, ASSE 1016 standard requires manufacturer’s instructions for installation, adjustment, and maintenance of the device to be packaged with each device. Please consider the 2021 UPC Section 408.9 Location of Valves and Heads. Control valves and showerheads shall be located on the sidewall of shower compartments or otherwise arranged so that the showerhead does not discharge directly at the entrance to the compartment so that the bather can adjust the valves before stepping into the shower spray.
- Point-of-use: the final outlet of the water supply system just prior to discharge to atmosphere.
SUBJECT: Indirect Waste Pipe Size and Length
SECTION: 803.3 (2024 UPC)
Question:
Section 803.3 states that indirect waste lines are required to be trapped if over 5 feet in length. Does this apply to all indirect waste lines including refrigeration coils, air conditioning equipment, and water treatment discharge?
Answer:
No, an exception is made for refrigeration coils and ice machines. There is no limitation on the length of indirect waste piping from this type of equipment. Please review additional code references.
801.3.1 Size of Indirect Waste Pipes. Except for refrigeration coils and ice-making machines, the size of the indirect waste pipe shall be not smaller than the drain on the unit, but shall be not smaller than 1 inch (25 mm), and the maximum developed length shall not exceed 15 feet (4572 mm). Indirect waste pipe for ice-making machines shall be not less than the drain on the unit and in no case less than 3 ⁄4 of an inch (20 mm).
801.7 Drip or Drainage Outlets. Appliances, devices, or apparatus not regularly classified as plumbing fixtures, but which have a drip or drainage outlets, shall be permitted to be drained by indirect waste pipes discharging into an open receptor through either an air gap or air break (see Section 801.3.1).
SUBJECT: Environmental, Class 1, and Class 2 Air Ducts.
SECTION: 502.2.1 (2024 UMC)
Question:
Table 403.7 classifies parking garage exhaust as Class 2. It appears the termination of Class 2 exhaust including parking garages will need to comply with 502.2.1. Is this an accurate interpretation?
Answer:
Yes, Table 403.7 does classify a parking garage as Air Class 2. Parking garages will need to comply with UMC section 502.2.1 unless the exception in footnote 3 of Table 403.7 applies to the installation:” (3) Exhaust shall not be required where two or more sides compose walls that are at least 50 percent open to the outside.” Once a determination of class 2 is established, section 502.2.1 location of termination would apply.
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Last modified: July 14, 2026