Scarborough Side Yards Leave Room to Cut a Proper Stairwell

Second units and basement work in Scarborough

Most of it went up between roughly 1950 and the mid-1970s as detached bungalows, side-splits and back-splits on wide lots — Bendale, Wexford-Maryvale, Dorset Park, Agincourt, Cliffcrest, Woburn. Those houses have something the semis and rowhouses west of Victoria Park usually don't: a real side yard. There is physical room to cut a proper stairwell beside the house, set the landing, the door swing and the stairwell drain where they belong, and get on with the job.

The splits are the other Scarborough advantage, and most contractors quote them like they're bungalows. On a side-split or back-split the lower level sits only partly below grade. You are often taking out three or four feet of soil instead of seven, and on a lot that falls off toward the rear — common through Cliffcrest, Guildwood, West Hill and anything running down toward the Bluffs or Highland Creek — you can frequently get a true walkout at grade and skip the stairwell entirely. A walkout rents better than a stairwell every time. It is worth having someone look at the grade before you assume you need a dig.

The honest catch in Scarborough is head height. These basements were poured for a furnace, a workshop and storage, not for tenants, and a lot of them come in tight. The Ontario Building Code gives secondary suites a lower ceiling than a standard finished basement — 1.95 m (6'5") through the habitable rooms, and 1.85 m (6'1") under beams and ducts. That difference is what makes or breaks a Scarborough suite, and it is why the duct and beam layout has to be planned before anyone frames a wall. Where the floor is genuinely too low, an underpin or a bench footing is the answer, and we will tell you which one your house actually needs rather than pricing the expensive one by default.

On the rules side, Toronto now allows up to four dwelling units as-of-right in a detached, semi-detached or townhouse property in every residential zone across the city, conversions included — and Ward 23 (Scarborough North) is the one suburban ward where Council has gone to six. A garden suite in the back yard is a separate permission on top of that. Between the lot sizes out here and those permissions, a Scarborough bungalow has more room to grow than almost any other house in the city.

HMH Construction is a licensed residential general contractor out of Mississauga with 25+ years in the trade, WSIB coverage and full insurance. We handle the drawings and the Toronto Building permit in-house — Scarborough addresses are reviewed out of the Scarborough district office at 150 Borough Drive — so you are not chasing a designer, an expediter and a builder separately. A standard separate entrance is typically a three-day build once the permit is in hand. Call 905-749-4608 for a look at your house.

Scarborough requirements

Units you're allowed — City of Toronto rules apply, not a suburban by-law

- Four units as-of-right, citywide. By-law 474-2023 (the Multiplex By-law) permits up to four dwelling units in detached houses, semi-detached houses and townhouses in all residential zones across Toronto, including conversion of an existing house. Detached-house built form standards apply; maximum height 10 m (or more where already permitted), maximum building depth 19 m on certain lots, and multiplexes are exempt from maximum FSI. - Six units in Ward 23 only. On June 25–26, 2025 Council adopted Official Plan and Zoning By-law amendments allowing residential buildings with up to six units in the Toronto & East York District and Ward 23, Scarborough North — the only suburban ward included. Ward 23 runs roughly from Highway 401 north to Steeles, and from Midland Avenue east to Neilson Road, covering Agincourt North, Milliken, Malvern and Morningside Heights. A citywide sixplex study is still underway. Confirm by address before designing to six. - Garden suites are additional. Garden suites are permitted citywide in R, RD, RS, RT and RM zones under By-law 569-2013 (Ch. 150.7/150.8). One garden suite containing one unit per property, regardless of lot size. Two storeys are possible, and a basement is allowed. Garden and laneway suites are separate accessory dwelling units and do not count toward the four-unit multiplex maximum. - Firefighter/emergency access to a garden suite is determined by an Ontario Building Code compliance review and cannot be varied by a minor variance. This is the single most common reason a Scarborough garden suite dies on paper — the access route to the rear yard is either there or it isn't. It gets checked first. - No parking required. Since February 2022 duplexes, triplexes and fourplexes are not required to provide parking on the property. - No development charges up to four units. Multiplexes are generally exempt from development charges and cash-in-lieu of parkland where there are no more than four units on the lot. - Multiple front entrances are allowed. The by-law permits multiplexes to have more than one front entrance, and the old restrictions on secondary-suite front entrances were removed. That matters in Scarborough where a front-facing walk-down often sits better on a wide bungalow lot than a side dig.

Permits and the legalization path

- A secondary suite is defined under By-law 569-2013 as self-contained accommodation with both food preparation and sanitary facilities, smaller in area than the primary unit. A building permit is required before any construction or legalization work begins — including legalizing a suite that already exists. - Scarborough addresses are handled by Toronto Building's Scarborough district office at the Scarborough Civic Centre, 150 Borough Drive, 3rd floor. In-person zoning appointments must be booked in the district the property is in. Toronto Building's line is 416-397-5330. - A separate licence applies to rooming houses, not to ordinary second suites. Since March 31, 2024 all multi-tenant (rooming) house operators need a City licence, and multi-tenant houses are now permitted citywide. In Scarborough — as in Etobicoke and North York — a maximum of six rooms is allowed in all zones. Former Scarborough did not permit them at all. Council approved further changes to the Multi-Tenant Houses By-law in December 2025, effective February 15, 2026. If you are renting by the room rather than by the unit, this is the regime you are in.

Ceiling height in the post-war stock

- Ontario Building Code secondary suite minimum: 1.95 m (6'5") in habitable rooms, 1.85 m (6'1") under beams, ducts and similar obstructions — lower than the 2.0 m a standard finished basement is held to. The 2024 Code extended this allowance rather than restricting it to houses over five years old. - Practical consequence in Scarborough: duct rerouting and beam boxing are design decisions, not field decisions. Get the mechanical layout drawn before framing, and only underpin where the numbers actually require it.

Ravines, the Bluffs, and TRCA land

Southern and eastern Scarborough carry more of this than the rest of the city. Lots backing onto the Scarborough Bluffs, Highland Creek, the Rouge and the Morningside ravine system can fall under the City's Ravine and Natural Feature Protection By-law (Toronto Municipal Code Ch. 658), which requires a permit to:

- harm or remove any tree, regardless of size; - change natural topography by excavation or by adding soil or other material on slopes; - place or dump fill; or - construct new — or replace old — structures and retaining walls.

Properties may also be regulated by the Toronto and Region Conservation Authority, which reviews building location, setbacks, grading, stormwater, slope stability, erosion, access and vegetation. A TRCA permit is separate from and in addition to a City ravine permit. Both add real time. Check the City's Ravine and Natural Feature Protection map against your address before you commit to a dig date.

Water in the basement

Scarborough is covered by the City's Basement Flooding Protection Subsidy Program — up to $6,650 per property, at 80% of cost: backwater valve up to $1,600 each (two devices), sump pump up to $2,250 plus $300 for a battery backup, plumbing assessment up to $500, and foundation drain severance and capping up to $400. Eligibility requires you to be the registered owner of a single-family, duplex, triplex or fourplex home, that eavestrough downspouts are disconnected from the sewer, zoning compliance, and no outstanding City debts. A building permit is required to install a backwater valve. If we are already opening the floor for a separate entrance or a suite, that is the cheapest hour you will ever spend on flood protection — the drain, the valve and the sump belong in the same scope.

One Scarborough quirk worth knowing

Not every Scarborough property is governed by the citywide Zoning By-law 569-2013. Parts of the former City of Scarborough remain under former municipal zoning by-laws, in whole or in part, depending on site-specific amendments, exceptions and appeals — By-law 9508 in the Dorset Park community, for example. It changes what setbacks and coverage you are working against. We confirm the governing by-law by address at the start of every job rather than assuming 569-2013.