BuildRules/Waterloo/Additional residential unit

Waterloo project guide

Do you need a permit for an additional residential unit in Waterloo?

Check Waterloo additional residential unit permit requirements for zoning, parking, drawings and the published 15-business-day review timeline.

1 min readReviewed Oct 1, 2026

The short answerConditional

Yes. Waterloo requires a building permit to add an additional residential unit to a home.

For basement or main-floor ARUs, the City also directs applicants to confirm zoning, parking and driveway requirements before filing.

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What changes the answer.

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

ARUBuilding permit requiredConditional

Waterloo states that a building permit is required to add an additional unit to a home.

Official sourceCity of WaterlooBuild an ARU on the main floor or basement · ARU building permit, zoning and drawing requirements

Verified2026-10-01Open proof

ZoningConfirm setbacks, parking and driveway dimensionsConditional

The ARU process directs applicants to confirm zoning and planning rules before applying.

Official sourceCity of WaterlooBuild an ARU on the main floor or basement · ARU building permit, zoning and drawing requirements

Verified2026-10-01Open proof

DrawingsExisting and proposed construction requiredInfo

The City’s ARU checklist requires site and floor plans showing property, parking and unit entrances.

Official sourceCity of WaterlooBuild an ARU on the main floor or basement · ARU building permit, zoning and drawing requirements

Verified2026-10-01Open proof

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Site plan
Existing and proposed floor plans
Parking and driveway dimensions
Unit entrance information
Project-specific structural/mechanical information

Open the focused permit checklist

Fees and timing

TimelineWaterloo lists a 15-business-day processing timeline for secondary dwelling units in houses once an application is complete.

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

Next steps

Confirm ARU type and property zoning
Plan parking and entrances
Prepare the complete drawing set
Submit the building permit application

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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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