London, ON suite & ADU rules

Permission first. Construction second.

Another dwelling on one property is both a planning question and a building-safety question. Do not collapse them into one permit check. London’s ARU guidance covers interior conversions, additions, garage conversions and detached units. A March 2026 bylaw amending ARU bedroom counts and unit size was appealed; the City states Interim Control By-law CP-1600-300 remains relevant while the appeal is unresolved. The city warns that not every lot qualifies; setbacks, lot dimensions, coverage, parking and current zoning have to be checked before the permit application.

Main home

Secondary / ADU

One property · more than one approval layer

Property address check

Check a London property by address.

Enter a street address. We will identify the municipality from the address; the zoning and approval status of this property still require a separate municipal check.

Property address

Uses Natural Resources Canada’s national Geolocator to match the address. The rule result comes from SuiteRulesCanada’s audited municipal source set.

Dedicated suite/ADU sourceReviewed 2026-09-20

Start with London’s current suite guidance

Open the official London suite source ↗

The broader Southwestern Ontario housing pattern does not replace the London approval file. Confirm this address and unit type with the local source.

Ontario: the provincial layer

The Ontario ARU framework can support as many as three units in the principal house, or two principal-house units plus one ancillary-building unit, on identified lands. Municipal zoning still controls site details.

Ontario additional residential unit framework ↗

Before applying in London

Confirm the zone, lot configuration, setbacks, parking and access for the exact address.

A building permit still has to address construction and safety requirements; a general citywide allowance is not a permit.

Can you build here?

What to verify before building in London.

This is the simple build-direction summary. The exact property still has to meet its zoning, site, servicing and permit requirements.

Internal additional unitConditional — verify

Detached garden / backyard unitConditional — verify

DuplexProperty-specific

TriplexProperty-specific

FourplexProperty-specific

Before you build: confirm the exact property, zoning and permit path with London.

Next planning steps

Confirm local zoning before you estimate project costs.

This guide explains the municipal process, not whether your specific property is approved. The next two steps are budgeting and contractor scoping; neither replaces municipal approval.

1 · BudgetEstimate renovation costs in LondonOpen the matching Home Cost Canada city page, then adjust the project and scope.Open cost planner →2 · ContractorFind a local contractorHomeSelect is a separate contractor-matching service. Use it after the zoning and permit path are understood.Start contractor match →

Planning sequence: rules → budget → written scope / contractor. Cost models and contractor matching do not determine whether the municipality will approve the work.

Municipal zoning: verified research register

Governing municipal bylaw: Zoning Bylaw Z.-1; 2026 parking amendments

Suite and ADU rules: Eligible lots may allow four residential units. No additional parking is required for ARUs under current City guidance; verify driveway/access and site-specific constraints. Interim Control Bylaw CP-1600-300 temporarily limits ARU bedrooms and size while the permanent amendment is under appeal.

Provincial versus local rules: Provincial ARU legislation does not establish property-specific permission. Requires manual municipal check for zoning overlays and any appealed amendment.

Current municipal source status — October 13, 2026

ELIGIBLE LOTS: UP TO THREE ARUs, WITH INTERIM RESTRICTIONS. London’s published guidance allows up to three additional residential units (four total dwellings) on qualifying properties, with no more than two ARUs in a detached building. No additional parking spaces are required for ARUs; additional driveways to serve an ARU are prohibited. These are general permissions, not a parcel approval.

Interim Control Bylaw CP-1600-300 remains relevant: The City says it adopted the permanent ARU amendment on March 3, 2026 but that it was appealed, so the interim limits continue during the appeal. The municipal rules describe a two-bedroom maximum per ARU, a combined three-bedroom maximum for additional units in/attached to the main building and another combined three-bedroom maximum for those in an accessory building, and an 80% gross-floor-area ceiling relative to the primary dwelling. Recheck the appeal disposition, zoning, setbacks, access, servicing, building permits and licensing before relying on any result.

Municipal source research, not comprehensive certification or a permit. Official source links remain at the bottom of this page.

Earlier municipal research notes (5)

Municipal evidence check · October 12, 2026

Confirmed for this claim: London’s March 3, 2026 ARU bedroom/size restriction amendment was appealed. The City says Interim Control By-law CP-1600-300 remains applicable while appeals are unresolved; therefore the proposed/adopted restrictions must not be presented as ordinary final zoning provisions without the interim-control context.

Still to verify: Verify current interim-control period, any Ontario Land Tribunal disposition and site-specific effect, alongside consolidated Z.-1 zoning and ARU permit conditions.

This is a targeted official-source review, not complete certification of every adopted amendment or approval for your property.

Priority evidence follow-up — October 12, 2026

Official-source finding: The City confirms interim-control Bylaw CP-1600-300 applies to ARUs while the March 3, 2026 permanent zoning amendment remains under appeal.

Not yet cleared: Do not apply the appealed permanent amendment as unconditionally operative. Verify any later Tribunal order and zoning/size/bedroom limits for the actual lot.

Evidence status: CONFIRMED INTERIM PENDING APPEAL. This is not a complete adopted-bylaw, zoning-map, appeal or property-specific approval determination.

Third-pass municipal evidence — October 12, 2026

Current finding: London states CP-1600-300 temporarily governs ARU bedroom and floor area limits while its March 2026 amendment is appealed. The City says up to three additional units on eligible properties, two in a detached building, and no additional parking required for ARUs.

Still requires verification: Check the current expiry/extension of interim control, any Tribunal decisions, mapped zoning and approval of the specific ARU layout.

Evidence level: INTERIM CONTROL CONFIRMED PARKING CORRECTED. Not a parcel-specific or complete legal approval.

Current legal-evidence reconciliation — October 13, 2026

Status: INTERIM CONTROL CONFIRMED — appeal unresolved. City guidance supports a maximum of three ARUs (four total units) on qualifying property, at most two ARUs in a detached building, and NO additional parking required for ARUs. Interim Control Bylaw CP-1600-300 imposes temporary bedroom/area restrictions; the March 3, 2026 amendment was appealed and the City says interim controls continue pending appeals.

What remains: Written/posted Ontario Land Tribunal final disposition not located in this review; confirm live zone, water/sewer, access, setbacks, 80% gross-floor-area limit, bedroom limits and permits per site.

Source: Official London ARU rules and appeal notice; full link listed under Official sources. No property-specific building, zoning or planning approval is implied.

Legal record update — October 13, 2026

Status: INTERIM CONTROL CONFIRMED — permanent amendment appealed. London’s current municipal notice says Council adopted permanent ARU limits March 3, 2026, followed by an appeal, and that Interim Control Bylaw CP-1600-300 continues to apply while appeals are unresolved. The City’s ARU guide also says no additional parking spaces are required for ARUs.

Still unverified: No official final tribunal disposition identified in checked sources. Verify the current interim-control validity, local zoning, size/bedroom requirements, servicing and permits for individual sites.

Official document: read the municipal evidence. This summary does not certify all later legal amendments or permit approval for any particular property.

How this guide was verified

Guide verification: Targeted municipal-source claim check recorded. This guide provides linked municipal research; a complete enacted-bylaw, zoning-map and amendment cross-check has not been documented for this municipality.

Property confidence: Not assessed. City-wide guidance does not confirm permission for a particular parcel. Check official zoning, overlays and permits. How verification works →

Official sources

City of London — additional residential units ↗

City of London — zoning information ↗

Ontario — Planning Act ↗

Municipal requirements and appeal status may change. Confirm the operative zoning by-law and any applicable tribunal decision before relying on a parcel count.

London — primary-source evidence checked October 12, 2026 ↗