Additional residential units

Learn about additional residential units (ARUs) and how to add them.

On this page

  1. What are additional residential units?
  2. Zoning regulations
  3. Required permits and licences
  4. How to add an additional residential unit
  5. Contact us

What are additional residential units?

Additional residential units (ARUs) are separate, self-contained dwelling units (with their own kitchen and bathroom facilities) located within a single detached, semi-detached or townhouse building, or in a backyard Coach House.


Zoning regulations

The City of Waterloo currently allows the creation of up to three units on a residential lot subject to compliance with Section 3.A.1B and 3.C.2 of Zoning By-law 2018-050. 

We are in the process of updating our zoning regulations, making it easier for community members to build additional residential units. Changes to the bylaw will allow the creation of up to four units and four storeys on residential lots.

Learn more about the upcoming bylaw amendment and share your feedback on Engage Waterloo.


Required permits and licenses

A building permit is required to begin construction of an additional residential unit. Visit the building permits page to apply for a home renovation or additions permit.

If you are planning on renting out an additional unit, you must apply for a rental license. Visit the rental licenses page to learn about the requirements and how to apply.


How to add an additional residential unit

The city is in the process of creating an online ARU toolkit to help homeowners understand the process, steps, and requirements for the construction of an additional residential unit.

Incentives to help offset the financial barriers that homeowners face in building market and affordable additional rental units are being investigated by city staff.

Learn more about the ARU toolkit’s development and share your feedback on Engage Waterloo. 


Contact us

If you have any questions, contact us by email at ARU@waterloo.ca.