How Many Restrooms Does a Commercial Space Need in Ohio?

A commercial space in Ohio needs the number of toilets, sinks and other fixtures set by Table 403.1 of the Ohio Plumbing Code, and that number comes from the building's occupant load, not from how many people you hire or how big the lease looks. For an office with an occupant load of 60, the table works out to four toilets and two sinks, or three toilets and two sinks if you build all-gender multi-user rooms. A restaurant, a retail shop and a warehouse each use different ratios. The building official makes the final call.

We're ACC Solutions, a Cleveland property management and rehab coordination company. We coordinate commercial plumbing with partner plumbing companies, and fixture counts come up in almost every tenant build-out. This post explains how the count is calculated so you can arrive at the walkthrough with the right questions. It is general information, not a code review of your building.

Step 1: Find the Occupant Load the Building Official Will Use

Section 403.1 says fixtures are provided "based on the actual use of the building or space" and that "the number of occupants shall be determined by the International Building Code." Ohio adds that when the actual load will be significantly different from the code figure, the building official may set an alternate basis, and that basis goes into the certificate of occupancy (Ohio Admin. Code 4101:3-4-01). In practice: ask the city building department or your architect which occupant load they are using before anyone prices fixtures.

Step 2: Pick the Right Row of Table 403.1

Table 403.1 (as reproduced for the Ohio Plumbing Code) uses these ratios for the most common commercial uses:

• Business (offices, banks, professional services, light industrial): water closets 1 per 25 for the first 50 people and 1 per 50 after that; lavatories 1 per 40 for the first 80 and 1 per 80 after that; drinking fountain 1 per 100; one service sink.
• Restaurants, banquet halls and food courts: water closets 1 per 75 for each sex; lavatories 1 per 200; drinking fountain 1 per 500; one service sink.
• Bars and taverns: water closets 1 per 40 for each sex; lavatories 1 per 75.
• Retail (mercantile): water closets 1 per 500; lavatories 1 per 750; drinking fountain 1 per 1,000; one service sink.
• Storage and warehouses: water closets 1 per 100; lavatories 1 per 100; drinking fountain 1 per 1,000; one service sink.

The footnotes matter. The table counts one fixture as the minimum for the number of people shown or any fraction of it, so a count of 51 people still needs the second fixture. For restaurants, the occupant load of seasonal outdoor seating and entertainment areas is included, so a patio can raise the count. For business and mercantile uses with an occupant load of 15 or fewer, a service sink is not required.

Step 3: Do the Math (a Labeled Example)

Illustration only: the numbers are made up. Say the building official sets an occupant load of 60 for a business space.

1. Separate men's and women's rooms. Section 403.1.1 divides the load in half, so 30 per sex. Water closets: 30 ÷ 25 = 1.2, rounded up to 2 for each sex, so 4 total. Lavatories: 30 ÷ 40 = 0.75, rounded up to 1 each, so 2 total.
2. All-gender multi-user room. Section 403.1.1, exception 2, calculates on 100 percent of the total load. Water closets: the first 50 at 1 per 25 is 2, plus 10 at 1 per 50 is 0.2, total 2.2, rounded up to 3. Lavatories: 60 ÷ 40 = 1.5, rounded up to 2. Urinals, if any, must sit in stalls.
3. Single-user rooms. Fixtures in single-user toilet rooms count toward the total, and those rooms are identified for use by anyone (403.1.2).
4. Add the rest of the row. One drinking fountain (1 per 100 people), though where fountains are required the code calls for at least two, one wheelchair-accessible and one for standing users, or one dual-spout unit (410.3.1). Plus one service sink.

That is the whole method. The same steps with the restaurant row (1 per 75 water closets for each sex) give a very different answer, which is why the row you're in matters more than the square footage.

Exceptions That Can Shrink the Count

• Small occupancies (403.2): separate facilities by sex are not required in a structure or tenant space with a total occupant load, employees and customers combined, of 15 or fewer; in mercantile uses with a maximum load of 100 or fewer; or in business uses with a maximum load of 25 or fewer.
• Quick-transaction spaces (403.3): public toilets are not required in takeout, pickup and drop-off spaces with a public access area of 300 square feet or less (employees still need facilities).
• Tiny buildings: Ohio's exception waives facilities in buildings under 100 square feet if fixtures are available within 500 feet.

Layout Rules That Trip Up Build-Outs

• The route can't pass through the back of house. The path to public toilets can't go through kitchens, storage rooms or closets (403.3.1), and toilet rooms can't open directly into a food preparation room (403.3.2).
• Distance and floors. Required facilities must be within 500 feet of travel and no more than one story above or below the space (403.3.3).
• Lavatory in the same room. The required lavatory sits in the same room as the toilet (405.3.2).
• Tempered water at public sinks. Public lavatories must deliver tempered water through an approved temperature-limiting device (419.5).
• No drinking fountains in restrooms (410.5), and none are required in a restaurant that provides free drinking water in a container (410.4).
• Doors. A multi-occupant toilet room's egress door can't lock from inside (403.3.6).
• Accessibility is a separate layer. Plumbing code points to the building code's accessibility chapter and ICC A117.1; the Americans with Disabilities Act applies on top. Have your architect confirm.

Where Counts Go Wrong in Real Projects

• Using headcount instead of occupant load. Ten employees can sit in a space with a far larger code load.
• Forgetting the patio. Outdoor seating is counted for restaurants.
• Forgetting the service sink. Most commercial rows list one, and it is easy to omit from a first plan.
• Reusing the old tenant's layout after a use change. A bakery that becomes a restaurant moves to a different row. Ask the building department whether the change of use triggers a new count.
• Treating a table as a permit. Fixture counts are reviewed with the plans; always confirm with the local building department or Ohio Department of Commerce review.

What ACC Does With This

If you're planning a build-out, call (216) 480-8899 or request a plumbing project review. Bring your floor plan, the intended use and the occupant load your architect or the building department gave you. ACC partners with several plumbing companies and coordinates the work, and we quote commercial plumbing after a walkthrough. We don't design the layout or set the count; the building official and your architect do. We help you price and schedule the plumbing once the count is known.

Related reading: rough-in and build-out plumbing in Cleveland, how to prepare for a commercial plumbing walkthrough, commercial water service from Cleveland Water and grease interceptor requirements.