PLUMBING

Section 2902 Minimum Plumbing Facilities

Key Points

Section 2902 Minimum Plumbing Facilities

2902.1   Minimum number of fixtures.   Section 2902.1 establishes the minimum number of plumbing fixtures that must be provided for various occupancies based on Table 2902.1. The table is based on the distinct occupancy classifications identified in Chapter 3 and the corresponding occupant loads calculated for the building. Those fixtures required in most occupancies include water closets, lavatories, drinking fountains, and service sinks. In addition, bathtubs or showers, automatic clothes-washer connections, and kitchen sinks are mandated in some residential occupancies. Bathtubs and/or showers are also required in specified institutional occupancies. It is assumed that at least one fixture of each type as required by Table 2902.1 will be provided in a building designed for human occupancy.

When determining the proper occupant load to be utilized in calculating plumbing fixture count, there is no specific methodology referenced. However, because the only provisions in the IBC® addressing occupant load calculation are found in Chapter 10, it is typically assumed that the approach established in Section 1004 for the means of egress should also be used for plumbing fixture count. The basis for most occupant load determinations, other than areas with fixed seating, is the density factor established in Table 1004.1.2. An occupant load is determined by dividing the floor area under consideration by the appropriate density factor. It should be noted that the building official also has the authority as established in the exception to Section 1004.1.2 to base the occupant load on the actual number of occupants anticipated, rather than the calculated number. Although the use of this exception is typically inappropriate for egress and fire safety purposes, it is commonly applied for plumbing fixture count. The occupant load utilized for egress and fire protection requirements is purposely conservative by most counts because of the life safety concerns. The occupant load to be used in calculating the minimum plumbing fixture count should be based on more of a convenience concern, recognizing the need to satisfy any sanitation issues. Therefore, the occupant load used in the plumbing fixture count could differ from that used as the basis for the design of the means of egress system. The building official should rely on all available information that will assist in the appropriate determination of occupant load for fixture count purposes.

2902.1.1   Fixture calculations.   Once the appropriate occupant load is determined, the minimum required number of fixtures is calculated by using Table 2902.1. The provisions of Section 2902.1.1 address the method in which the fixtures are to be distributed between the sexes.

For the determination of required plumbing fixtures, the total occupant load to be served by the plumbing facilities must first be calculated. Unless modified by special conditions, the total occupant load is then halved, assuming 50 percent of the occupants to be male, 50 percent to be female. The resulting occupant loads are then used when applying the table, with fixtures calculated individually for each of the sexes. Where the required number of fixtures contains a fraction, an additional fixture is required. See Application Examples 2902-1 and 2902-2. Note that the provisions of Section 419.2 of the IPC allow urinals as a substitution for water closets on a 1-to-1 basis, provided that, in assembly and educational occupancies, urinals account for no more than 67 percent of the required fixtures. For example, if nine water closets are required in a men’s toilet room in a large nightclub, it is acceptable to provide six urinals and only three water closets. Where the occupancy classification is other than Group A or Group E, only one-half of the required number of water closets may be substituted with urinals.

Application Example 2902-1

Application Example 2902-2

The determination of the minimum plumbing fixture count becomes a bit more complex where the building contains a number of different occupancies. If toilet room facilities are provided independently for each of the occupancies in the building, the basic method of calculating the number of fixtures should be satisfactory. However, if common toilet facilities are designed to serve the occupants from multiple occupancy groups, a different approach is more appropriately warranted. In such a determination, the number of required fixtures for each sex would be calculated for each occupancy, then without rounding, added together to arrive at the minimum fixtures that must be provided. An example of this methodology is shown in Application Example 2902-3. A similar approach could be utilized when substituting urinals for water closets.

Application Example 2902-3

2902.2   Separate facilities.   In most buildings where plumbing fixtures are required, separate facilities must be available for each sex. Simply, at a minimum, one women’s toilet room and one men’s toilet room must be provided. There are conditions, however, where only a single toilet room is mandated. Separate-sex facilities need not be provided within dwelling units and sleeping units. In addition, common facilities are permitted where the number of people (both customers and employees) does not exceed 15. In mercantile occupancies with an occupant load of 100 or less, such as a small retail sales tenant, a single toilet room is also permitted.

2902.2.1   Family or assisted-use toilet facilities serving as separate facilities.   Where each separate-sex toilet room is required to only have a single water closet, the required separate restrooms are permitted to be designated as “family or assisted-use” toilet facilities versus requiring the facilities to be designated for each sex. Allowing the toilet facilities to be used by either sex provides greater flexibility and increases overall availability.

Where facilities are designated for a specific sex and the toilet room for one of the sexes is occupied or being cleaned, then a person needing that facility is typically forced to either wait, or sneak in and use the toilet room that is designated for the other sex. This provision requires that two separate facilities be provided, but by eliminating the separate-sex designations, both of the restrooms are available to anyone and the overall availability in small establishments is increased.

The selection of the term “family or assisted-use” toilet facilities is important because it influences how the toilet rooms are constructed. Sections 1109.2.1.2 through 1109.2.1.7 provide several details that affect the construction of these toilet rooms. While all of the requirements of these sections are applicable, the main provisions to review are Sections 1109.2.1.2, 1109.2.1.6, and 1109.2.1.7.

2902.3   Employee and public toilet facilities.   Only specific occupancies and uses are required to have public toilet facilities for use by customers, patrons, and visitors of the building. Restaurants, nightclubs, places of assembly, business uses, mercantile occupancies, and similar buildings and tenant spaces intended for public use must be provided with customer toilet facilities located within one story above or below the area under consideration, and with a path of travel not to exceed 500 feet (152,400 mm). Those uses where public use is not expected, such as warehouses, factories, and similar buildings, only require employee toilet facilities.

Two types of public-use buildings are exempted from public toilet facilities, open and enclosed parking garages having no parking attendants, and small quick-transaction tenant spaces. Pizza carryouts, dry cleaners, ATM facilities, shoe repair shops, newspaper stands, and many other similar spaces are unique in that patrons spend a short period of time completing a transaction and then depart. It should be noted that it is the public-access area and not the entire business that is regulated by the 300-square-foot area limitation. This allowance is illustrated in Figure 2902-1.

Figure 2902-1