iPermit offers building permit services Markham homeowners, builders and investors use for the whole path to an issued building permit: zoning checks, permit drawings, technical coordination and the upload to the City’s ePLAN portal. Markham is not a simple city to permit in. Its zoning has been rewritten, council’s decision on extra units was reversed in March 2026, four neighbourhoods have heritage controls, and the City’s own review times double when an application goes in incomplete.
Most residential lots in Markham with a detached, semi-detached or townhouse can generally have up to three units under Ontario’s additional residential unit rules. This can include the main home plus two additional units. Local zoning rules still apply and can affect what is allowed on a specific property. If a proposed fourth unit is not permitted by the zoning it may require a zoning change or other planning approval before a building permit can be issued.
Adding a third or fourth unit to an existing house is still a serious building project. The City’s conversion guide sets out requirements that owners often don’t expect:
A licensed architect has to design stacked-unit buildings over 600 m², and every three- or four-unit building must also be registered with Markham Fire and Emergency Services after construction. We work out which code path fits the age of your house before the layout is drawn, because that one decision changes the cost of the whole conversion. Our residential building permits cover basement units, additions, garden suites and new homes.
Until 2024, Markham ran on 46 separate zoning by-laws written between 1954 and 2004, each covering a different part of the city. Council replaced most of them with Comprehensive Zoning By-law 2024-19, enacted on January 31, 2024. Most of them, not all: lands rezoned by amendments passed after June 12, 2014, and certain lands identified under the 2014 Official Plan sit outside the new by-law and keep their own rules.
That is why the first job of a building permit consultant Markham owners hire is to confirm which document actually governs the lot, then check setbacks, height, coverage and unit rules against it. The City offers a Property Details Search, and for new single detached houses it also runs a Zoning AI PreCheck that returns a pass or fail with feedback rule by rule. It’s a useful first filter, but it doesn’t replace a full zoning review of the drawings. If the design can’t comply, the next step is a minor variance at the Committee of Adjustment, and that hearing has to happen before the permit.
Three local approvals catch Markham projects more often than anything in the Building Code.
Heritage districts. Thornhill, Markham Village, Buttonville and Unionville are heritage conservation districts. Any exterior alteration, new construction or demolition there needs a Minor or Major Heritage Permit. Staff can approve work that follows the district guidelines, but every demolition request goes to Council.
Trees. A permit is required to injure or remove a tree with a trunk of 20 cm (about 8 in.) or more, measured 1.37 m above ground. The City reviews tree applications within 45 days of payment, and new houses, demolitions and grading work may also need a Tree Assessment and Preservation Plan from a qualified arborist. On a tight infill lot, a mature tree in the side yard can shape the whole design.
Lot grading. New homes, additions and accessory buildings need lot grading approval. Properties near the Rouge River and Don River valleys may also fall under the Toronto and Region Conservation Authority, which issues its own permits.
Every property starts from a different place, but in Markham the order matters: the lot’s zoning and local approvals come first, so the drawings are only prepared once.
Confirm the address, current use, any open permits or past work on record, and whether the property sits in one of Markham’s four heritage districts.
Identify the zoning by-law that governs the lot, then flag anything that has to come before the permit: a heritage permit, a tree permit, lot grading or TRCA review.
Prepare existing and proposed plans, coordinate structural, HVAC or plumbing input where needed, and complete the energy efficiency forms and unit declaration the City asks for.
Upload a complete package to the ePLAN portal, then answer examiner comments and resubmit within the agreed scope until the permit is issued.
Each type of project in Markham runs into its own set of rules. These pages go deeper into the one you’re planning.
Interior alterations, wall removals and kitchen or bathroom changes, with plumbing and mechanical work permitted as part of the same application.
Basement units designed around the fire separation, sound and egress rules that apply to your house’s age, plus registration with Markham Fire.
Rear, side and second-storey additions checked against the zoning by-law that governs your lot, with lot grading approval and tree protection planned in.
Decks, balconies and covered porches, including heritage review when the property sits in Unionville, Markham Village, Thornhill or Buttonville.
Detached and attached garages, with the lot grading approval Markham requires for accessory buildings and the setback checks that decide where one can go.
Confirming whether By-law 2024-19 or one of the older by-laws covers your lot, before a single drawing is started.
Markham charges most residential permits by floor area. These are the 2026 rates from the City’s fee schedule:
Project | 2026 City fee |
New single detached house | $22.08 per m² |
Infill residential house | $24.75 per m² |
Multiple-unit residential, under 4 storeys | $27.42 per m² |
Secondary suite (alteration) | $22.08 per m² |
Unfinished basement | $7.53 per m² |
Deck, balcony or covered porch | $151 each |
Minimum residential permit fee | $151 |
Two details are worth noticing. A house replacing an older one on an established street is billed at the infill rate, about 12% more per square metre than the same house in a new subdivision. And every application starts with a $100 non-refundable pre-application fee. Our fee for drawings and coordination is separate and quoted after we look at the property, since a secondary suite and a custom infill home are very different jobs.
Markham publishes two review clocks for every permit type: one for a complete application and a longer one for an incomplete one. The complete clock starts once the pre-screen is approved. The incomplete clock starts only after the estimated fees are paid in full.
Permit type | Complete (business days) | Incomplete (business days) |
Houses and small projects | 10 | 20 |
Accessory apartment | 15 | 20 |
Small buildings | 15 | 30 |
Large buildings | 20 | 40 |
Complex buildings | 30 | 40 |
Demolition | 10 | 20 |
Our building permit application services Markham clients rely on are built to land in the first column. For a house, a complete package means the application form, designer schedules, the applicable law checklist, a site plan, architectural, structural and mechanical drawings, energy efficiency documentation and a declaration letter stating the total number of dwelling units. Drawings must come from a BCIN-registered designer or a licensed professional.
After the first review, the file goes back and forth until the examiner has nothing left to raise. A permit expediter Markham builders trust keeps those rounds few and short: every comment answered, every affected sheet revised, one clean resubmission. We handle that work within the agreed scope. The City still decides, and no one can promise its timeline.
Tell us about your project, and the iPermit team will review your requirements and help identify the right engineering, permit, or approval services for your next step.
Before you hire any building permit company Markham homeowners are comparing, ask three things: who takes legal responsibility for the drawings, who checks zoning, heritage and tree rules before design, and who answers the examiner. iPermit is based in Vaughan, next door in York Region, and the organization behind it has served the Ontario permit market since 2006. Our Markham work includes an exterior alteration with a new deck and pergola, and we handle commercial permits as well as residential ones. We coordinate the design and permit work in the agreed scope, while the City reviews, issues the permit and inspects.
Most Markham permit questions we get aren’t about the Building Code. They’re about the rules around it: how many units a lot can hold after the mayor’s veto, when a separate permit is needed, and what happens to a file that stalls. Here are the answers to the ones that come up most, based on the City’s current rules.
Not as of right. Since the March 2026 veto, a fourth unit needs a zoning by-law amendment or a variance approved for your specific property. We can assess whether your lot is a realistic candidate before you spend money on drawings.
Not if the plumbing is part of a larger project, such as a basement unit or addition. A standalone plumbing permit is only needed when plumbing is the main work.
The pool enclosure does. Markham issues a separate pool enclosure permit for the fence and gates around a pool.
Any building permit Markham has on file that stays inactive for six months or more may be treated as abandoned. If your project has stalled, it’s worth responding to outstanding comments before that point.
Both the Building Standards department and heritage staff. The heritage permit covers the exterior design, and the building permit covers the construction. We plan the two together so the drawings don’t have to be redone for one after the other.
