The Town of Stouffville has partnered with Duncan Patterson Architecture to develop pre-approved or “ready to use” ancillary ARU designs and conceptual multiplex designs to help increase housing supply and types in Stouffville.

These designs are part of the recently approved Affordable Housing Community Plan (CIP), which is a key initiative from the Town’s Housing Accelerator Fund agreement with Canada Mortgage and Housing Corporation (CMHC). These designs are part of the Town’s commitment to support increasing housing supply, encourage gentle infill, and simplify the approval processes for constructing ARUs and multiplexes in the Town.

• Additional Residential Unit (ARU) is a self-contained dwelling unit with a private kitchen, bathroom facilities and sleeping areas within or as an ancillary building or structure to a single detached, semi-detached or townhouse dwelling.
• Multiplexes are homes with multiple dwelling units, such as triplexes and fourplexes.

The Town has prepared four (4) pre-approved ARU ancillary design plans being offered to homeowners in the following options: two (2) studio unit, and two (2) one-bedroom unit options in contemporary and traditional styles. Each pre-approved design has been reviewed for consistency with the Town’s Official Plan, Zoning By-law, and Urban Design Guidelines. These design plans will be offered as part of a three-year program to homeowners in the Town.

Design Features

• Stamped and compliant with the Building Code.
• Complete ARU design plan packages available with each design option.
• Designed for use on most residential lots in the Town.

Key Benefits

• Safe and Secure with all with pre-approved ARU ancillary designs meeting the Building Code.
• Faster approvals and timelines with all pre-approved ARU design plans meeting Building Code requirements, this can streamline the building permit approval process.
• Reduced design costs as all pre-approved ARU designs plans are free of charge.

Homeowners must still comply with the Town’s Official Plan, Zoning By-law, and obtain a building permit prior to any construction (see FAQs for more information).

Homeowners can choose from up to four (4) pre-approved ARU designs:

The Betz – One Bedroom – Concept Rendering

The Betz – (One Bedroom) – Floor Plan

“The Flint” - Pre-approved ARU Design (Studio) – Concept Rendering

“The Flint” - Pre-approved ARU Design (Studio) – Floor Plan

“The Forsyth” - Pre-approved ARU Design (One Bedroom) – Concept Rendering

“The Forsyth” - Pre-approved ARU Design (One Bedroom) – Floor Plan

“The George” - Pre-approved ARU Design (One Bedroom) – Concept Rendering

“The George” - Pre-approved ARU Design (One Bedroom) – Floor Plan

Complete drawing packages are available upon request through Development Services (see How to Get Started).

Homeowners interest in the pre-approved design may also be eligible for select affordable rental incentives being offered by the Town:

• Multiplex/ARU Affordable Rental Grant
• Accessible Design Top-Up Rebate Please visit Affordable Rental Incentives for information.

Please visit Affordable Rental Incentives for information.

The Town has prepared three (3) conceptual multiplex designs, with two (2) traditional architectural styles and one (1) contemporary architectural style.

These designs demonstrate how multiplex housing can be integrated into existing neighbourhoods and maintain the neighbourhood character while encouraging gentle infill and density.

Multiplex Concept Designs Neighbourhood #1

Multiplex Concept Designs Neighbourhood #2

Multiplex Concept Designs Neighbourhood #3

• ARU Project Webpage
• Council Report – DS-021-26 Multiplex and Pre-approved Additional Residential Units Design Report
• Committee of Adjustment and Minor Variances
• Official Plan, 2025
• Comprehensive Zoning Bylaw
• Building Permits
• Affordable Housing Rental Incentives