Multiplex Toronto Builders builds fourplexes across Toronto, East York, Scarborough, Etobicoke, North York and the GTA, on standard, corner and narrow infill lots. Under EHON, four units are as-of-right on residential lots citywide, and we turn that permission into four rentable units that pass inspection. Every fourplex is delivered under HCRA registration with Tarion enrolment per project, WSIB coverage and a $5M CGL policy. Scope is set in CAD against the Ontario Building Code, and we coordinate with the Toronto Committee of Adjustment, Toronto Building, Toronto Water, Toronto Hydro and your insurer from the first site visit.
Fourplex projects go wrong in the same few ways. A sixplex is pitched where only a fourplex is as-of-right, severance gets mixed up with multiplex approval, EHON setback math is never run on a 25-foot lot, or a parking variance is promised without a Committee of Adjustment application behind it. We keep fourplexes inside OBC Part 9 wherever the design allows, and plan for Part 3 when it does not. Insulated glazing meets the energy code, 316 stainless fasteners go in within 500 metres of the lake, and zoning is verified through GeoWarehouse before you sign.
Most fourplexes cost $500K-$1.4M CAD and take 9-12 months from permit to occupancy with a crew of 4-6. We build in Toronto, East York, Scarborough, Etobicoke, North York, York, Vaughan, Markham, Richmond Hill, Mississauga, Brampton and Pickering, and every project carries a written workmanship warranty.
Fourplex construction sits under our wider multiplex construction service. If your lot is narrow, read can you build a fourplex on a 25-foot lot before you commit to a design.
Types of Fourplex Construction
Fourplex on a Standard Lot
On a typical Toronto lot of 30 to 40 feet, a fourplex usually fits in a three-storey form without a variance. We model the building envelope first: front and rear yard setbacks, side yards, the height limit (generally 10m to 12m depending on zone), floor space index where it applies, lot coverage and the soft landscaping percentage. Then we fit units inside it. Most standard-lot fourplexes end up with two-bedroom units around 800 to 1,000 sqft each, separate entrances and in-unit laundry. That unit size rents well across the city and keeps construction cost inside the $500K-$1.4M band.
Corner Lot Double-Frontage Fourplex
A corner lot gives you a second street frontage, which is a real design advantage. Two units can have their own front doors on the flanking street, so nobody walks down a long side path at night. The trade-off is a flankage setback on the side street and a sight triangle at the corner where you cannot build. We design corner fourplexes so each facade looks like a front, which helps both rentability and Committee of Adjustment goodwill if a variance is ever needed.
Narrow Lot Fourplex With Variance
On 25-foot lots, side-yard setbacks eat into the buildable width fast. Many narrow lots fit two or three units comfortably without a variance, and four only with a side-yard reduction. We run the numbers both ways. If a fourth unit adds enough rent to justify 4-6 extra months at the Committee of Adjustment, we file the variance, prepare the neighbour notice and represent you at the hearing. Our Leslieville fourplex on a 25x120 lot took exactly that route and still hit 11 months from feasibility to occupancy.
Rear-Garage Conversion
Some lots have a detached rear garage on a public lane. Under Toronto’s laneway and garden suite permissions, that structure can sometimes become a separate dwelling, or be replaced with one. Paired with a triplex in the main house, it can deliver four units with less work on the main building. We check lane access, fire access paths, servicing routes and rear-yard depth before recommending it.
Energy Code and Toronto Green Standard Tier 1
New fourplexes must meet the Ontario energy code, and Toronto adds the Toronto Green Standard. We build to Tier 1 as standard: continuous exterior insulation, R-24 walls, R-60 roof, high-performance casement windows, an air barrier verified by a blower door test, and ductless heat pumps or multi-zone HVAC with an HRV per unit. Tier 1 adds roughly 2-4% to hard costs. Tier 2 adds 6-10% and can support financing programs that reward efficiency.
Common Fourplex Problems in Toronto
EHON Setback Math Fails on a 25-Foot Danforth Village Lot
Symptom: EHON says four units, but every concept for your 25-foot Danforth Village lot either breaks a setback or produces units too small to rent. Immediate action: Ask for a setback and coverage model before paying for concept design. Scope: On many 25-foot lots, the side-yard and rear-yard rules leave room for two or three good units without a variance. Qualified contractor response: We model a triplex with no variance against a fourplex with a side-yard variance and show the rent, cost and timeline of each. Sometimes the triplex wins on total return because it starts 4-6 months sooner and has larger units. When the fourplex wins, we file and argue the variance ourselves.
Parking Variance Required on a Downtown Fourplex
Symptom: Your fourplex design has no parking, and the examiner’s comments say parking is required. Immediate action: Confirm whether the transit-proximity parking reduction applies to your lot. Scope: Many lots near the TTC need little or no parking, but not all. Without the reduction, you need a parking variance, which adds 4-6 months and neighbour notice. Qualified contractor response: We check the parking standard at feasibility, not after the permit application. If a variance is unavoidable, we file it early so it runs alongside design, and we include bike storage and transit distances in the application to support it.
Sixplex Pitched Where Only Fourplex Is As-of-Right
Symptom: A builder has told you your North York or Etobicoke lot can take six units. Immediate action: Ask for the zone confirmation in writing. Scope: Six units are permitted only in the Toronto and East York District and Scarborough Ward 23 North. Everywhere else, four is the as-of-right maximum. Qualified contractor response: We confirm your parcel’s district through GeoWarehouse and By-law 569-2013. If six is not allowed, we design the best fourplex the lot can carry, and check whether a garden suite adds a fifth unit legally. One Etobicoke client came to us with sixplex drawings that could never get a permit. We redesigned it as a fourplex, filed the CoA application and reached occupancy in 11 months.
HCRA Registration Lapse Mid-Project
Symptom: Mid-build, you discover your builder’s HCRA registration has lapsed or Tarion enrolment was never completed. Immediate action: Look up the builder in the HCRA Ontario Builder Directory and ask for the Tarion enrolment confirmation. Scope: Every new home in Ontario must be built by an HCRA-registered builder and enrolled with Tarion per project. Without that, deposit protection and warranty coverage are at risk. Qualified contractor response: We name the licensed entity in your contract, share registration details before any deposit, and complete Tarion enrolment before mobilization. WSIB clearance and the $5M CGL certificate sit in your project file from day one.
