Renovation & Construction in Thornhill
Thornhill is one of the GTA's most established and affluent communities, split down Yonge Street between the City of Vaughan on the west and the City of Markham on the east. Its mix of heritage homes in Old Thornhill, executive properties in Bayview Glen, German Mills and Royal Orchard, and pockets of estate lots makes it well suited to custom homes, high-end full renovations and large additions. Nexon Build works across both sides of Yonge, matching the calibre of construction to the neighbourhood and building every project to the Ontario Building Code.
Custom homes, high-end full renovations and large additions for Thornhill homeowners on both the Vaughan and Markham sides of Yonge Street. As a licensed renovation and construction company, Nexon Build manages feasibility, permits, scheduling, and quality control in Thornhill — every project tracked in Buildertrend so you always know where things stand.
Our services in Thornhill
Thornhill neighbourhoods we serve
We build and renovate throughout Thornhill, in York Region, including:
Building & permits in Thornhill
Thornhill is known for established executive homes, heritage properties, and estate lots. We manage the full permit process with the City of Vaughan or the City of Markham, depending on which side of Yonge Street the property sits on, including any Committee of Adjustment or minor-variance review your project requires — so your Thornhill build stays compliant and on schedule from day one.
Renovation costs in Thornhill
Renovation costs in Thornhill track the wider GTA market: kitchens from about $30K, bathrooms from about $15K, full home renovations $150K–$800K+, and ground-up custom homes at $350–$650 per square foot. Your number depends on scope, finish level, and the condition of the existing home.
See the full Toronto renovation cost guide, or get a free estimate for your Thornhill project in under 60 seconds.
The Building and Renovation Picture in Thornhill
Thornhill is not a single housing stock but several, and the right project depends on where in the community a home sits. Old Thornhill, around the Yonge and Centre Street heritage district, holds century homes and mid-century houses on mature, tree-lined lots where the character of the streetscape matters and heritage considerations can come into play. Bayview Glen and the estate pockets off Bayview carry larger executive homes and generous lots that support ground-up custom builds and substantial additions. German Mills and Royal Orchard are solid post-war and 1970s-80s suburban neighbourhoods where the housing is sound but dated, and where full gut renovations and second-storey additions let owners keep the location while modernising the home entirely. Knowing which of these you are working in shapes everything from the design approach to the permit path.
For most of our Thornhill clients the work falls into three buckets. The first is the custom home, where an older or undersized house on a good lot is replaced with a new build sized to the family and the neighbourhood. The second is the high-end full renovation, where the structure is worth keeping but the interior, mechanical systems and finishes are taken back to studs and rebuilt to current standards. The third is the large addition or extension, most often a rear extension or a full second storey that adds the space a growing family needs without leaving an established street. Each of these suits Thornhill's lots and price points, and each demands a builder who can carry a fixed-price scope on a significant investment rather than treating it as a light cosmetic job.
Permits, Zoning and the Committee of Adjustment in Thornhill
The single most important thing to understand about building in Thornhill is that it straddles Yonge Street across two municipalities. Properties on the west side of Yonge are in the City of Vaughan, and properties on the east side are in the City of Markham, with both cities sitting inside York Region. That means the permit authority, the zoning by-law, the fee schedule and the Committee of Adjustment that governs your project all depend on which side of Yonge your home is on. A custom home on the Vaughan side goes through Vaughan's building department and Vaughan's Committee of Adjustment; the same project a few blocks east goes through Markham's building department and Markham's Committee of Adjustment. We confirm the correct municipality at the outset so the application goes to the right city the first time.
Structural, plumbing and HVAC work all require building permits from the applicable city, and we pull every one the scope demands rather than working around them. Electrical work is handled differently in Ontario: it is permitted and inspected by the provincial Electrical Safety Authority (ESA) rather than the municipal building department, so we file that notification with ESA and coordinate its inspections alongside the City's. Where a design needs relief from the zoning by-law — for example a side-yard setback, lot coverage or height that a large addition or custom home would exceed — that goes to a minor variance application before the Committee of Adjustment for Vaughan or Markham, depending on the side of Yonge. Building without the right permits is where homeowners get caught later, at resale, at insurance-claim time, or when a future buyer's inspector flags unpermitted work. We manage the full application, coordinate the drawings the City needs, and schedule the inspections at each milestone so the project clears the Ontario Building Code with the municipal and ESA record to prove it.
What Building and Renovating Costs in Thornhill in 2026
Thornhill's projects tend to sit at the higher end of the GTA range because the homes and expectations are larger, but the underlying 2026 numbers are the same ones we use across the region. Custom home construction runs $350 to $650 per square foot, so a 3,000 square foot home works out to roughly $1.05M to $1.95M to build before land, design and soft costs. Full home renovations start around $150K for a mid-level refresh, move to $250K–$450K for a full gut with standard finishes, and reach $450K–$800K and up for premium work; a full gut generally lands at $200 to $450 per square foot. Additions and extensions cost $400 to $700 per square foot of new space, and a full second-storey addition typically comes in around $300K to $550K all-in — a common figure in German Mills and Royal Orchard where owners are adding a storey rather than moving.
On the room-by-room side, kitchen renovations range from about $30K for a refresh to roughly $75K mid-range and $150K and up for full custom, which is where a lot of Thornhill kitchens land. Bathrooms run $15K–$25K for a standard renovation and $35K–$60K and up for a primary ensuite. Basement finishing runs $50K–$80K for a legal apartment where the ceiling height works, and where it does not, underpinning to gain that height adds roughly $70 to $150 per square foot, or about $35K to $85K. We price every Thornhill project as a fixed-price scope so you know the number before the work starts, and we track the build in Buildertrend so the schedule, selections and any approved changes are documented as the job progresses rather than settled by argument at the end.
How Nexon Build Works in Thornhill and Why Choose Us
Nexon Build is a licensed, insured custom home builder and renovation contractor, and in Thornhill we work the way the community's homes deserve: a clear fixed-price scope, drawings that satisfy whichever city has jurisdiction, and construction built to the Ontario Building Code with City inspections at every milestone. Our design-build approach means we can take a Thornhill project from concept and drawings through permits and construction under one roof, which matters when a custom home or large addition has to clear a Committee of Adjustment before a shovel goes in the ground. We coordinate the trades, pull the permits the scope demands on the correct side of Yonge, arrange the ESA electrical permit, and keep the job tracked in Buildertrend so you can see selections, schedule and approved changes as the build moves.
Our completed work spans exactly the kinds of projects Thornhill calls for — custom homes and full renovations like Kemano, Davenport, Timberline, Canoe, Lambeth, Tatlin and Wren, along with focused rooms such as the Yonge bathroom and the Georgetown and Sultana kitchens. That range is the point: a Thornhill homeowner planning a luxury renovation, a custom build or a home addition is hiring a contractor who has carried significant fixed-price scopes to completion, not a crew learning on their house. If you are weighing a home renovation in Thornhill, a custom home on an estate lot, or a large addition on an established street, we will walk the property, confirm the right municipality, and give you a scope and price you can plan around. Call Nexon Build at (647) 829-0272 to start the conversation.
Common questions — Thornhill
Does Nexon Build serve Thornhill?+
Yes — Thornhill is one of our active service areas, including Old Thornhill, Bayview Glen, German Mills, Royal Orchard. We handle custom homes, home additions, full renovations, and kitchen, bathroom, and basement work across York Region.
Do you handle building permits in Thornhill?+
Yes. We manage the full permit process with the City of Vaughan or the City of Markham, depending on which side of Yonge Street the property sits on, including any Committee of Adjustment or minor-variance review your Thornhill project requires.
How much does a renovation cost in Thornhill?+
Renovation costs in Thornhill track the wider GTA market: kitchens from about $30K, bathrooms from about $15K, full home renovations $150K–$800K+, and ground-up custom homes at $350–$650 per square foot. Your number depends on scope, finish level, and the condition of the existing home.
What kinds of homes do you renovate in Thornhill?+
Thornhill is known for established executive homes, heritage properties, and estate lots. We renovate, extend, and rebuild across all of it — modernizing systems and layouts while respecting each home's character.
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