A legal basement Markham will register needs three approvals, in this order: a building permit for the suite, final inspections from Building Standards, and a registration inspection by Markham Fire & Emergency Services. Skip the last one and the unit is built but not legal to rent as a second unit. As GTA building permit consultants, we plan the drawings around all three from the start, because the fire registration checks things a permit set can miss.
The same path applies whether you are building a new basement apartment or bringing an existing one up to code. Our legal basement permit service handles both. Before any design work, check your property against the site rules in Markham’s Secondary Suites Guide for Homeowners, summarized below.
| Eligibility check | Markham rule | How to confirm |
|---|---|---|
| House type | Detached, semi-detached or row townhouse | Property survey and title |
| Parking | One space for each unit, each at least 2.75 m by 5.8 m; no street parking for the suite | Driveway measurements on a site plan |
| Access path | At least 1.2 m wide from the street to the suite entrance | Site plan showing the route |
| Entrances | One entrance per main wall facing the street, unless the second is below grade | Front elevation of the house |
| Ceiling height | 1.95 m in general areas, 1.85 m under beams and ducts | Measurements taken in the basement |
Is a legal basement in Markham allowed on your lot?
For most owners of a house in an urban residential zone, yes. Ontario’s Planning Act, as amended by Bill 23, stops municipalities from prohibiting up to three units on an eligible urban residential lot, so a suite inside a detached, semi-detached or row house is generally allowed, subject to the site rules above. A third unit, such as a garden home or coach house, follows separate City guides and should be planned at the same time if you want both.
The site rules are where Markham projects usually stall. A narrow driveway that cannot fit two full spaces, or a side yard too tight for the access path, can stop a basement apartment before the Building Code comes into it. Measure the driveway and side yard first, then decide where the suite entrance goes. If the best option is a new door in the side wall, a side entrance permit can be designed into the same drawing set.
Building Code checks for a secondary suite in Markham
Once the lot works, the Ontario Building Code decides the layout. Four areas carry most of the design effort in a secondary suite Markham reviews.
Fire separation. The suite has to be separated from the main unit. In a house less than five years old, Markham’s guide calls for a continuous smoke-tight barrier of at least 15.9 mm Type X gypsum board on both sides of the walls and on the underside of the floor above. In an older house, the separation needs a 30-minute rating, or 15 minutes where interconnected smoke alarms are installed.
Smoke alarms. Alarms are needed on every storey, in each bedroom, outside sleeping areas and in service rooms, interconnected across both units by wiring or wirelessly, with a visual signal component.
Exits and bedroom windows. Occupants must reach an exit without travelling more than one storey and without passing through the other unit. A basement bedroom also needs a window openable from inside without tools, with at least 0.35 m² of unobstructed opening, no dimension under 380 mm and a sill no higher than 1,000 mm above the floor. Many existing basement windows fail on sill height alone, which means cutting the foundation for a larger opening and a window well.
Heating and ventilation. Markham’s guide calls for each dwelling unit to have its own heating system, with no air ducts connecting the two units. A shared furnace with ducts running into the basement is one of the most common reasons an existing suite needs mechanical redesign.
Drawings and documents for a basement apartment permit in Markham
A basement apartment permit Markham issues is a Housing (HP) permit, submitted only through the City’s ePLAN portal. Paper applications are no longer accepted. The application needs the Building Permit Application Form, the Applicable Law Checklist, an Energy Efficiency Design Summary and, where plumbing changes, the Plumbing Data Housing Form.
The drawings have to show the existing and proposed floor plans, fire separations and their assemblies, bedroom window sizes, smoke and carbon monoxide alarm locations, the heating and ventilation layout, and a site plan with parking and the access path. They must be prepared by a designer with a Building Code Identification Number (BCIN), a licensed architect or a professional engineer, although homeowners may design their own at their own risk. Structural changes such as a lowered floor usually need an engineer as well.
Basement apartment permit steps, fees and timeline in Markham
- Pay the $100 non-refundable pre-application fee in ePLAN, then upload the forms and drawings.
- Pay the permit fee. For applications made after December 31, 2025, the rate for a secondary suite is $22.08 per square metre of floor area, with a $151 minimum for residential work.
- Answer any examiner comments and receive the approved documents. You print the permit card, the placard and one set of approved plans for the site.
- Book inspections through the City’s Inspections Portal: framing, plumbing and mechanical rough-in, insulation and vapour barrier, fire separations and fire stopping, then occupancy.
- Contact Markham Fire & Emergency Services to book the registration inspection.
Markham aims to finish the first review of a complete house application within 10 business days, and 20 for an incomplete one. The City says a permit can take anywhere from 10 to 40 days, with incomplete drawings and zoning mistakes as the usual causes of delay.
Markham second suite registration with Fire Services
Markham second suite registration is required under the City’s Occupancy Registration of Two-Unit Residential By-law 2018-57, which requires every two-unit house to be registered. After occupancy, the Fire Prevention Division inspects both units. Have proof of home insurance covering two units, the Electrical Safety Authority inspection, confirmation of working smoke and carbon monoxide alarms, the dryer and kitchen exhaust duct check and the attached garage door check ready for the visit. The City lists a $260 fee for the initial fire inspection and $246 for the registration itself.
If you own a house with an older suite that was never registered, start with Fire Services rather than a permit application. They will confirm whether a Two-Unit House Declaration Form applies or whether the suite needs a building permit and full inspections before it can be registered.
The Markham suites that move quickly are the ones checked against parking, access, fire separation and heating before the drawings start, and registered as soon as the occupancy inspection passes. Confirm current zoning and fees with the City on the day you apply, since both change. If you are weighing a new basement apartment or legalizing an existing one, send us the property address, basement photos and any existing drawings for a second-unit feasibility review.