The short answer: Commercial occupancies generally must provide drinking fountains based on occupant load, per the plumbing fixture tables (IBC Table 2902.1 / IPC Table 403.1), and where fountains are required they must be accessible — typically a bi-level ("hi-lo") arrangement so both wheelchair users and standing users are served (A117.1 / IBC Chapter 11). A common configuration is a bi-level fountain with an integral bottle filler. Some occupancies and small spaces are exempt or allowed alternatives (for example, certain occupancies may substitute bottled water or be exempt below a threshold), and bottle fillers may count toward or supplement the requirement depending on the edition. The exact counts, exemptions, and whether a bottle filler substitutes for a fountain come from the adopted edition.
When fountains are required
The fixture tables require drinking fountains for most occupancies, scaled by occupant load. As with other fixtures, you read the required number from the table for your occupancy and round up.
The accessible bi-level requirement
Where a drinking fountain is required, accessibility rules generally require it to serve both a person using a wheelchair and a standing person — satisfied by a bi-level (hi-lo) unit or two fountains at the two heights. A single standard-height fountain typically does not satisfy the requirement alone.
Bottle fillers
Bottle-filling stations are common and often combined with the bi-level fountain. Whether a bottle filler counts toward the required fountain count (versus being a supplement) depends on the adopted code edition — confirm rather than assume.
Exemptions and alternatives
Some occupancies, and spaces below certain thresholds, are exempt or may use alternatives (e.g., bottled water in defined cases). Don't assume a fountain is required everywhere — but don't assume it's exempt either; check the table and exceptions.
Common review comments
Required drinking fountain omitted.
Single-height fountain where the accessible bi-level arrangement is required.
Bottle filler assumed to satisfy the fountain requirement when the edition doesn't allow the substitution.