Shared houses and small multiplexes need a written rule for hydro, water, and gas. Ontario does not let you improvise that after move-in.
Submetering
Each unit gets its own meter. Tenants pay what they use. Electricity submetering needs an OEB licence. Natural gas submetering is not allowed in Ontario. New buildings take this more easily than a 1920s duplex.
Ratio utility billing (RUBS)
No extra meters. The bill is split by a formula — square footage, heads, bathrooms. Cheap to start. Easy to argue about if nobody saw the formula in the lease.
Flat monthly fee
One number every month. Simple budgets, weak incentive to turn the heat down, and risk for the owner if a winter spike lands above the fee.
Put it in the Standard Lease
Name the utilities, who pays which, the method, due dates, and what happens if a bill is late. Sample math in the file prevents March surprises. If you want that drafted with the rest of the lease, ask about leasing.