March 13, 2025
From the 2024 UPC Illustrated Training Manual, Chapter 4, PLUMBING FIXTURES AND FIXTURE FITTINGS
408.7 Shower Compartments. Shower compartments shall have a finished interior in accordance with the following:
(1) Not less than 1024 square inches (0.6606 m2).
(2) Be capable of encompassing a 30 inch (762 mm) circle.
The minimum required area and dimensions shall be measured at a height equal to the top of the threshold and a point tangent to its centerline. The area and dimensions shall be maintained to a point of not less than 70 inches (1778 mm) above the shower drain outlet with no protrusions other than the fixture valve or valves, showerheads, soap dishes, shelves, and safety grab bars, or rails. Fold-down seats in accessible shower stalls shall be permitted to protrude into the 30 inch (762 mm) circle.
Exceptions:
(1) Showers that are designed to be in accordance with ICC A117.1.
(2) The minimum required area and dimension shall not apply for a shower receptor having overall dimensions of not less than 30 inches (762 mm) in width and 60 inches (1524 mm) in length.
SHOWER RECEPTOR AREA
The shower, whether a one-piece stall or one built up on the site, is a plumbing fixture. It will be the responsibility of the plumber to ensure the shower is tested and is watertight. Install the manufactured shower per the manufacturer’s
instructions as well as all the requirements set forth in Chapter 4.
Figure 408.7 illustrates how to size the area of the shower. The dimensions must be maintained to a height of 70 inches in the shower.
Exception (1) to the requirements is for showers that meet ICC/ANSI A117.1, Standard on Accessible and Usable Buildings and Facilities which include accessible shower compartments such as roll-in or curbless types.
Exception (2) is for the retrofit of a bathtub to a shower. This will allow the tub to be replaced with a shower in the same dimensions.
From the 2024 UMC Illustrated Training Manual, Chapter 6, DUCT SYSTEMS
603.11 Underground Installation. Ducts installed underground shall be approved for the installation and shall have a slope of not less than 1/8 inch per foot (10.4 mm/m) back to the main riser. Ducts, plenums, and fittings shall be permitted to be constructed of concrete, clay, or ceramics where installed in the ground or in a concrete slab, provided the joints are sealed and duct is secured in accordance with SMACNA HVAC Duct Construction Standards – Metal and Flexible. Metal ducts where installed in or under a concrete slab shall be encased in not less than 2 inches (51 mm) of concrete, secured in accordance with SMACNA HVAC Duct Construction Standards – Metal and Flexible.
DETAIL OF EMBEDDED DUCT
Ducts are required to “be made substantially airtight” in Section 603.9; however, this requirement is primarily intended to prevent moisture from the ground or moisture and concrete from entering the duct system if embedded in concrete. Figure 603.11 illustrates a typical detail for embedded ducts. Underground ducts must be sloped to drain to an accessible point in the event that water enters the duct through the openings. The slope requirement is consistent with SMACNA HVAC Duct Construction Standards.
(This is not to be considered the official position of IAPMO, nor is it an official interpretation of the Codes.)
IAPMO
IAPMO develops and publishes the Uniform Plumbing Code®,the most widely recognized code of practice used by the plumbing industry worldwide; Uniform Mechanical Code®; Uniform Swimming Pool, Spa and Hot Tub Code®; and Uniform Solar Energy, Hydronics and Geothermal Code™ — the only plumbing, mechanical, solar energy and swimming pool codes designated by ANSI as American National Standards — and the Water Efficiency Standard (WE-Stand)™. IAPMO works with government, contractors, labor force, and manufacturers to produce product standards, technical manuals, personnel certification/educational programs and additional resources in order to meet the ever-evolving demands of the industry in protecting public health and safety.
Last modified: March 13, 2025