Legislative Report

Kook Dean
V.P. Legislative
June 2019


From the 2018 UPC Guide to Important Code Changes

What Changed.

402.4 Wall-Hung Fixtures. Wall-hung fixtures shall be rigidly supported by metal supporting members so that no strain is transmitted to the connections. Floor-affixed supports for off-the-floor plumbing fixtures for public use shall comply with ASME A112.6.1M. Framing-affixed supports for off-the-floor water closets with concealed tanks shall comply with ASME A112.6.2. Flush tanks and similar appurtenances shall be secured by approved non-corrosive screws or bolts.

Why It Changed.

This change creates a specific reference for standards currently in the code. By moving the requirements after the first sentence, it clarifies that the reference is to specific groups or products that are regulated by the two standards.

Additionally, the reference to the standard identifies the exact product that is being regulated. Hence, any floor affixed support for off the floor plumbing fixtures for public use would have to meet the standard. This does not require this type of attachment, as many sinks and lavatories are also attached by wall hangers. However, when a floor-affixed support is used, it must comply with the standard. The standard identifies the sizing and strength requirements for the supports. The same would be true for framing-affixed supports.

What It Means to Me.

Wall-hung water closet installation requirements are contained in Section 402.6 stating that they are to be connected to an approved carrier. This section refers to other fixtures that are wall mounted, such as lavatories, sinks or urinals. All must be supported by the proper mounting device, whether it is by mounting plates, brackets, or arms and not the drainage connection for framing-affixed supports with concealed tanks.

Engineers and designers will be required to ensure in their plans and specifications that all public use plumbing fixtures that incorporate floor-affixed supports for off-the-floor plumbing fixtures, that the supports comply with the new language.

Plans examiners and inspectors shall verify the plans and specifications that the supports for public use off-the-floor plumbing fixtures meet the minimum required listings. Field inspectors should verify the supports installed on the job are the appropriate listed supports.

Plumbers, installers or technicians need the knowledge and experience to recognize the appropriate listed supports for public use off-the-floor plumbing fixtures are being installed where required.

From the 2018 UPC Illustrated Training Manual, Chapter 5, Water Heaters

510.2.21 Vent Connector Sizing.

Vent connectors shall not be increased more than two sizes greater than the listed appliance categorized vent diameter, flue collar diameter, or draft hood outlet diameter. Vent connectors for draft hood equipped appliances shall not be smaller than the draft hood outlet diameter. Where a vent connector size(s) determined from the tables for fan-assisted appliance(s) is smaller than the flue collar diameter, the use of the smaller size(s) shall be permitted provided that the installation complies with all the following conditions:

(1) Vent connectors for fan-assisted appliance flue collars 12 inches (300 mm) in diameter or smaller are not reduced by more than one table size [e.g., 12 inches to 10 inches (300 mm to 250 mm) is a one size reduction] and those larger than 12 inches (300 mm) in diameter are not reduced more than two table sizes [e.g., 24 inches to 20 inches (600 mm to 500 mm) is a two size reduction].

(2) The fan-assisted appliance(s) is common vented with a draft hood-equipped appliance(s).

(3) The vent connector has a smooth interior wall. [NFPA 54:13.2.24]

A sudden, large expansion of the vent connector diameter creates a pressure drop that may limit the draft and encourage condensation. Therefore, this section places a limit on upsizing, limiting the vent connector diameter to two sizes larger than one of the following, whichever is applicable:

  • Appliance-categorized vent connector diameter;
  • Flue collar diameter; or
  • Draft hood outlet diameter.

Note that an appliance includes either a draft hood or flue collar for connection to the vent or vent connector. The term “appliance-categorized vent diameter/area” is defined as follows:

The minimum vent area/diameter permissible for Category I appliances to maintain a nonpositive vent static pressure when tested in accordance with nationally recognized standards.

Therefore, where connecting an appliance to a vent connector, use the applicable tables in Section 510.0 to find the minimum size vent connector. Note that only smooth wall vent connectors may be downsized. It would also be advisable to check with the manufacturer to make sure it allows a downsizing.