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OBC DIVISION B · PART 9 · SECTION 9.31 — PLUMBING FACILITIES

Which fixtures need hot and cold running water in an Ontario home?

Every dwelling must have a potable water supply, with cold water piped to every fixture and hot water to kitchen sinks, lavatories, bathtubs, showers and laundry areas. A service water heater is therefore effectively mandatory in every dwelling unit.

Code reference
Dwelling units must be supplied with potable water, and the distribution system must deliver cold water to all fixtures and hot water to fixtures used for washing, including kitchen sinks, lavatories, bathtubs, showers and laundry facilities. Equipment for heating service water must be installed to serve these fixtures, with installation details governed by Part 7.
OBC Division B, Subsection 9.31.3.

Paraphrased for clarity — open this provision in the BUILDAiD Library for the exact wording.

What this means in practice

The practical consequences show up in renovations and rural projects. A dwelling on a well still needs a pressurized potable supply and a water heater; a cottage conversion to year-round dwelling must be piped for hot water at the required fixtures. Under Part 7, scald protection matters too: storage water heaters are typically set around 60 C to control Legionella, while shower valves must be pressure-balanced or thermostatic to limit delivered temperature. Undersized or missing hot water to a basement suite is a frequent legalization deficiency.

Plain language

Your home must have safe drinking water, cold water at every fixture, and hot water at every sink, tub, shower and laundry hookup. A working water heater is not optional; it is a code requirement.

Related questions

What plumbing fixtures must every dwelling unit have in Ontario?Is a floor drain required in the basement of a house in Ontario?

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This page is provided for general information. Building code requirements depend on your specific project, occupancy and municipality, and code editions change. Always verify requirements against the current Ontario Building Code and confirm with your local building department.