BuildRules/Whitby/Additional dwelling unit

Whitby project guide

What do you need for an additional dwelling unit in Whitby?

Check Whitby ADU requirements for building permits, zoning, inspections, registration and the current Housing Accelerator Fund incentive deadlines.

1 min readReviewed Oct 1, 2026

The short answerConditional

Whitby requires the applicable building permits and registration for ADUs, with property eligibility governed by zoning and Town requirements.

Whitby accepts principal-residence and detached ADU permit applications and requires registration with Enforcement Services. A temporary incentive program is available for qualifying permits under 2026 deadlines.

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What changes the answer.

Start with these conditions. The official reference is attached to each one.

Building permitRequiredConditional

Whitby provides a dedicated building permit process for Additional Dwelling Units.

Official sourceTown of WhitbyAdditional Dwelling Units · ADU eligibility, permits, inspections and registration

Verified2026-10-01Open proof

ZoningConfirm property eligibilityConditional

The Town directs owners to review zoning and submit a Planning Inquiry to verify whether an ADU is permitted on the property.

Official sourceTown of WhitbyAdditional Dwelling Units · ADU eligibility, permits, inspections and registration

Verified2026-10-01Open proof

RegistrationRequiredConditional

Whitby states that all property owners with an ADU are required to register the unit with the Town.

Official sourceTown of WhitbyAdditional Dwelling Units · ADU eligibility, permits, inspections and registration

Verified2026-10-01Open proof

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ADU building permit application
Required drawings and design guide information
Zoning/property information
Electrical Certificate of Acceptance before registration where applicable

Open the focused permit checklist

Fees and timing

TimelineConfirm the current municipal review timeline after the application is accepted as complete.

FeesConfirm the current Whitby permit fee for the exact project class before filing.

Next steps

Confirm ADU type and zoning eligibility
Prepare the permit package
Complete required inspections
Register the completed ADU with the Town

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BuildRules principle

Do not confuse “no permit” with “no rules.”

Zoning, overlays, safety rules and other constraints can still apply.

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