Basement Renovations in Oshawa

Durham Region

Basement Planning in Oshawa

That range extends into newer growth areas like Taunton and Windfields, where subdivision-built homes are now old enough to need their first real update.

What Oshawa Says About Second Units

Every municipality writes its own rulebook for basement apartments, and Oshawa is no exception. It is not exciting reading, but it is far cheaper than finding out the hard way. Here is what the City of Oshawa published on its own page when Reno Rise reviewed it (September 2026).

• Under Oshawa’s Two Unit House Registration By-law, every two-unit house must be registered, and failing to register is an offence under the by-law.
• Units created before July 1994 register with an application and a declaration form once they meet property standards, Building Code and Fire Code requirements.
• Units created after July 1994 need a building permit before the second unit is created.

Read the source before you plan: City of Oshawa: additional or second unit information. Rules, fees and program deadlines change, so confirm with the municipality. Oshawa is outside the City of Toronto, so Toronto Building’s rules do not apply; the legal secondary suite guide explains the general considerations.

Whatever the age of the house, the plan starts the same way: measure the ceiling height, look for signs of moisture, and decide whether you want a finished basement or a self-contained suite. Get those answers early and the rest of the project gets calmer. See basement renovation planning, underpinning, waterproofing and egress windows for the most common issues.