Do I need a Heritage Vaughan review for an addition in Kleinburg?

Yes. Any addition or significant exterior change in Kleinburg requires Heritage Vaughan review. The character requirements are strict — material palette, roof pitch, massing, fenestration. We work with architects who understand the requirements and we coordinate the heritage submission alongside the building permit.

How do you handle a second-storey addition over an existing one-storey home?

We engage a structural engineer to assess the existing foundation and framing for the added load, design any required reinforcement, and detail the lateral-load resistance for the new upper floor. The construction phase typically requires a roof-off period of 4 to 8 weeks where the existing structure is exposed; most clients move out for that window and we weather-protect the assembly.

How long does a Vaughan permit take for an addition?

Standard residential addition permits at City of Vaughan Building Standards run 6 to 12 weeks. Heritage Vaughan involvement on Kleinburg or designated Woodbridge properties adds 4 to 8 weeks. We submit during construction documentation rather than after, which compresses the overall calendar.

Home Additions · Vaughan

Vaughan Home Additions — Second-Storey & Rear Extensions

Significant additions across Vaughan — Thornhill second-storey adds, Maple rear extensions, and Kleinburg estate-scale expansions.

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01Home Additions in Vaughan

The local angle.

Vaughan additions tend to be substantial. The 1980s-90s estate-scale homes in Thornhill and Maple have generous lots that support both rear and side additions; the Woodbridge stock often supports second-storey additions over an existing one-storey footprint. Kleinburg additions have a heavier design constraint — the character requirements that Heritage Vaughan enforces on Kleinburg properties shape the material palette, the roof pitch, and the massing.

Vaughan Building Standards runs a thorough permit review for additions, including structural review, mechanical review, and where applicable Heritage Vaughan review. Standard residential addition permits run 6 to 12 weeks. Heritage involvement on Kleinburg or designated Woodbridge projects adds another 4 to 8 weeks.

Vaughan pricing in 2026 reflects scope and ambition. A rear single-storey addition runs $475 to $650 per square foot for mid-range finishes; a second-storey addition runs $550 to $750 per square foot; estate-scale Kleinburg additions with custom millwork and stone exteriors clear the upper end of those ranges. Total project budgets typically land $400,000–$1,000,000 depending on size.

02What’s Included

Local scope highlights.

City of Vaughan Building Standards permit handling for additions including structural and mechanical sub-permits

Heritage Vaughan coordination for Kleinburg and designated Woodbridge properties

Architect coordination including engagement with Vaughan-experienced firms when the project does not have one

Structural engineering for second-storey additions over existing one-storey footprints — common in Woodbridge and Maple

Tree protection planning where mature trees on the property are subject to municipal protection requirements

Stone, brick, and material continuity matching for additions where the existing exterior must read as one composition

A Vaughan home addition usually starts with a structural decision: out, or up. The Thornhill and Maple lots support meaningful rear and side additions without crowding the property line, so out is often the lower-friction option. Where the lot is constrained by setbacks or the brief calls for matching the existing roof line, up is the answer — and the second-storey addition becomes a structural project on top of an architectural one.

Heritage Vaughan involvement is the recurring Kleinburg-specific discipline. The character requirements there are strict and well-defined — the material palette, the roof pitch, the massing. We work with architects who understand the requirements rather than discovering them at heritage review, and we coordinate the heritage submission alongside the building permit so the two reviews run in parallel.

Material continuity is the recurring detail problem on Vaughan additions. The existing house is brick or stone, the addition has to read as part of the original composition rather than as something stuck on. We source matching brick where the original is still in production, find close matches where it is not, and detail the transitions — courses, corners, soffits — so the eye does not catch them. The same discipline applies to roof slate, stone surrounds, and trim profiles.

The construction phase runs 4 to 7 months on site for most rear additions and 6 to 9 months for second-storey adds. The mechanical integration — extending HVAC, plumbing, and electrical through the existing house — is the routine work that determines whether the existing house stays comfortable through the build.

03Cost Guidance

What it actually costs.

Cost guide · Updated April 2026

What a home addition costs in Toronto in 2026

A rear single-storey addition in Toronto runs $450 to $650 per square foot. A second-storey addition runs $550 to $750. Committee of Adjustment can add five months. Here is when not to add at all.

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05Local Questions

Asked in Vaughan.

Home Additions in Vaughan?

Tell us about the project. We respond inside one business day with availability and next steps.

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Vaughan Home Additions — Second-Storey & Rear ExtensionsVaughan Home Additions — Second-Storey & Rear Extensions