9.1 Number of Water Closets or Urinals
Every occupancy is required to have at least one water closet, the number of water closets depend what the building is used for. The National Building Code states the number of water closets for assembly occupancies shall conform to the table below. Assembly occupancy means the use of the building by a gathering of people for, political, social, or for the consumption of food or drink.
Occupancies are given a maximum number of people allowed inside by the inspection division and the fire marshal.
One water closet can serve both sexes in commercial occupancy if the occupant load is not more than 10 people or the total area is less than 100 m2.
| Number of Persons of Each Sex |
Minimum Number of Water Closets | |
| Male | Female | |
| 1 – 50 | 1 | 2 |
| 51 – 75 | 2 | 3 |
| 76 – 100 | 2 | 4 |
| 101 – 125 | 3 | 5 |
| 126 – 150 | 3 | 6 |
| 151 – 175 | 4 | 7 |
| 176 – 200 | 4 | 8 |
| 201 – 250 | 5 | 9 |
| 251 – 300 | 5 | 10 |
| 301 – 350 | 6 | 11 |
| 351 – 400 | 6 | 12 |
- Assembly occupancy (theatre, union hall) with 140 people (70 male and 70 female) would require 2 water closets for males and 3 water closets for females.
- Assembly occupancy with 256 people (128 male and 128 female) would require 3 water closets for males and 6 water closets for females.
The maximum occupancy number is divided in half for male and females unless the occupancy is only for males or females. (female gym)
Primary schools and day cares require 1 water closet for every 30 males and 1 water closet for every 25 females.
Places for worship and undertaking premises require 1 water closet for each sex for every 150 people.
Residential homes require 1 water closet for each sex for every 10 people. At least 1 water closet must be installed in every dwelling unit.
Business and personal services occupancy shall conform to the Table below (law office or hair salon).
| Number of Persons of Each Sex |
Minimum Number of Water Closets for Each Sex |
| 1 – 25 | 1 |
| 26 – 50 | 2 |
| Over 50 | 3 plus 1 for every 50 persons of each sex |
Mercantile occupancy (retail stores) shall have 1 water closet for each 300 males and 1 for each 150 females.
One lavatory must be provided for a room containing 1 or 2 water closets or urinals and at least 1 additional lavatory must be supplied for additional 2 water closets or urinals.
Industrial occupancy shall conform to the Table below. (oil refinery or ship yard)
| Number of Persons of Each Sex |
Minimum Number of Water Closets for Each Sex |
| 1 – 10 | 1 |
| 11 – 25 | 2 |
| 26 – 50 | 3 |
| 51 -75 | 4 |
| 76 – 100 | 5 |
| Over 100 | 6 plus 1 for every additional Increment of 30 persons of each sex in excess of 100 |
Urinals are permitted to substitute for two thirds the number of male water closets required.
If 6 male water closets were required, two thirds could be urinals. You could install 2 water closets and up to 4 urinals.
The building code also requires that a floor drain be installed in a washroom containing a urinal with a automatic flushing device. (flush tank urinal)
- The minimum spacing between urinals is 24” centre to centre.
- The minimum spacing between water closets is 30” centre to centre.