TLDR: Custom home builds in Scarborough typically land between $1.25 and $1.75 million for 2,500 to 4,000 square feet, and the wide postwar lots are the reason the math works at all. We are based in the Scarborough Bluffs, our own family home is one of our builds at 21 Scarborough Heights Boulevard, and we have two custom builds underway in the neighbourhood in 2026, at 84 Cliffcrest Drive and 24 Scarcliff Gardens. Here is what we tell homeowners deciding whether their lot deserves a new house.

Most families who call us about a custom home in Scarborough are not shopping for a builder yet. They are wrestling with a harder question: we love this street and this lot, so do we renovate, add on, rebuild, or give up and move?

Here's the truth no one selling you a new house will say: if you own a bungalow in Birch Cliff, Cliffside, Cliffcrest, Guildwood, or Port Union, you already own the hardest thing to buy in Toronto. The house can be changed. The lot cannot.

Scarborough lots are the best-kept secret in Toronto home building

Scarborough offers some of the best lot sizes in all of Toronto to build your dream home. The postwar bungalows in the Bluffs neighbourhoods sit on wide, deep, mature lots that the old city core cannot match. A lot like that keeps every option open: full interior renovation, second-storey addition, or complete custom rebuild. It is why we do more additions and custom builds in southern Scarborough than anywhere else we work.

Two features of these lots catch homeowners off guard when nobody raises them early.

Ravine protection

Sections of Scarborough near the Bluffs and the creek corridors are ravine protected, which brings the TRCA and the City's ravine bylaw into your approval path. That does not kill a project, but it shapes what you can build and how long approvals take. We review ravine proximity at the start of every Scarborough project, before design money is spent, so expectations are set on day one rather than at permit time.

Mature trees

Large mature lots come with large mature trees, and Toronto's tree protection rules are not a straightforward process. Whether a tree can be removed, injured, or even built near is a permit question with real timelines attached, and we walk our homeowners through it, because getting it wrong mid-project costs far more than planning for it up front.

The pattern in both cases is the same: none of this is a problem when it is surfaced in week one, and all of it is a problem when it is discovered after the drawings are finished. That is the core argument for hiring a builder who knows these streets.

The addition-or-rebuild math

What most homeowners get wrong is treating this as renovate-or-move. In Scarborough the real decision has three rungs, and each has a price band we can back with completed projects.

Home additions run $500,000 to $1,000,000 here depending on size and complexity. Our Midland project came in around $1,000,000 all in, and that included underpinning, a full interior renovation, an $80,000 kitchen, and a complete second level, substantially more than a straight top-up. A bungalow-to-second-storey addition that touches less of the existing house lands in the $500,000 to $700,000 range. Our Scarborough Bluffs home addition guide covers that path in detail.

Custom homes and new builds start above $1,000,000 and usually land between $1.25 and $1.75 million for 2,500 to 4,000 square feet, on land you already own.

Additions win most of the time in this part of Toronto. The honest caveat: squeezing your family's needs into an addition can create design constraints a custom home would never impose.

When the custom home wins: 84 Cliffcrest Drive

The family behind our 84 Cliffcrest build started exactly where most of our clients start, evaluating a home addition. Partway through that evaluation they realized the addition was not going to check every box for their forever home. They transitioned to a custom build, spent more than the addition would have cost, and got a house that fits the family with nothing compromised.

Most of our custom home clients were evaluating a move before they called us. They love their lot. What they want is a house that deserves it.

What a real custom home budget looks like

Between $1 and $2 million for 2,000 to 4,000 square feet, depending on scope and finish level. The number matters less than how you arrive at it. We show custom home clients a real budget from a real build, line by line, before they commit to anything, because a fixed-price project is only fixed if the budget included everything at the start. We broke down the full cost picture in what it actually costs to build a custom home in Toronto.

Three lines consistently surprise people seeing a full build budget for the first time:

HST. On a new build it is a six-figure line, and the rebate rules cover far less than most people assume.
Site and utility upgrades. New hydro service, water and sewer connections: the invisible work that happens before the visible work.
Finishing. Proper painting alone on a custom home runs $40,000 and up, and trim, doors, and hardware scale with it.

Budgets that leave these lines out do not make a project cheaper. They make the surprise bigger.

The BVM approach: budget before drawings, on streets we know

We give clients a real construction budget before they spend money on architectural drawings, not after. On a custom home, that sequencing protects you from the most expensive mistake in this industry: designing a house you cannot afford to build.

And we do it locally. We are based in the Scarborough Bluffs, and our completed projects cover Fishleigh Drive, Kildonan Drive, Midland, Minerva, 396 Rouge Highlands, 87 Scarborough Heights Boulevard, and 151 Phyllis Avenue in Cliffcrest, a full custom build you can still tour virtually. Our own family home at 21 Scarborough Heights Boulevard is one of our builds. When we say we know what a Cliffcrest lot will and will not allow, that is not marketing copy. It is our commute.

Four questions to ask any builder before you sign

How local are you? Hire a builder who is local to your area and knows the properties, soil, lots, and constraints. Ask for examples of similar projects completed in your area, with addresses.
How do you fit into design and pre-construction? A builder with a real pre-construction process protects your budget and reduces risk before a shovel moves. If pricing only shows up after the drawings are done, that is your warning.
Are they open book? Do they invite you to job sites? Show you their contract early? Talk about references without flinching? Test the transparency before you depend on it.
Do you actually like them? Design and construction together commit you to well over a year with this team. Make sure you like them.

Key Takeaways

Custom home builds in Scarborough typically cost $1.25 to $1.75 million for 2,500 to 4,000 square feet; home additions run $500,000 to $1,000,000.
The Bluffs neighbourhoods (Birch Cliff, Cliffside, Cliffcrest, Guildwood, Port Union) hold some of the best building lots in Toronto, which is what makes rebuilding beat moving.
Ravine protection and mature-tree rules shape many Scarborough projects; both are manageable when reviewed before design starts.
The budget lines that surprise people most: HST, site and utility upgrades, and finishing, where proper painting alone runs $40,000 and up.
An addition wins on price most of the time; a custom home wins when the addition cannot check every box, which is exactly what happened on our 84 Cliffcrest Drive build.
Get a real construction budget before paying for drawings, from a builder who can show you completed projects on nearby streets.

Frequently Asked Questions

How much does it cost to build a custom home in Scarborough?

Between $1.25 and $1.75 million for most 2,500 to 4,000 square foot builds, on land you already own. Smaller builds can come in under that, and complex lots push above it. Ask for a line-item budget, not a per-square-foot guess.

Can I rebuild on a ravine lot in the Scarborough Bluffs?

Usually yes, with conditions. Ravine-protected portions of a property bring TRCA and City ravine bylaw review into the approvals, which affects siting, grading, and timeline. Have the proximity reviewed before design begins; it changes what is worth drawing.

Should I build an addition or a custom home?

Run the math both ways. In Scarborough an addition typically costs $500,000 to $1,000,000 and a custom build $1.25 to $1.75 million. If the addition checks every box for how your family lives, it wins. If you are compromising the design to avoid a rebuild, price the rebuild before deciding. The gap is often smaller than expected once you account for what the addition cannot fix.

Thinking about building in Scarborough?

We will show you a real budget from a real Scarborough build before you spend anything on drawings. Book a 30-minute consultation and bring your hardest questions. That is what they are for.