Kopman Build designs and builds second-storey additions in Don Mills — converting bungalows to two-storey homes, adding master suites, and doubling liveable area without moving. Full permit management included.
Don Mills's 1950s and 1960s planned community homes are the primary candidates for second-storey addition. When a family has outgrown a single-storey home but loves their neighbourhood, building up is almost always more cost-effective than buying up.
A second-storey addition is the most structurally complex residential project type. It involves assessing the existing foundation and floor structure for load capacity, removing the existing roof, constructing the new floor and roof system, and integrating new mechanical systems — all while the family often continues living in the lower floor.
Kopman Build manages the full structural assessment, engineering coordination, architectural design, permit process, and construction. In Don Mills, this includes navigating the City's zoning requirements for height, setbacks, and lot coverage — and identifying any heritage-adjacent complications early in the process.
Complete conversion of a single-storey Don Mills home to a two-storey — new floor plan, stairs, and exterior.
Adding a partial second storey over part of the home — typically over the main living area or garage.
Adding a new primary bedroom, ensuite, and walk-in closet as a second-storey addition.
Adding two or three bedrooms and a bathroom above the existing main floor.
Foundation and floor structure assessment before design begins — essential for accurate budgeting.
Second-storey addition combined with main-floor renovation for a complete home transformation.
We visit your Don Mills property, review your goals, and document the project — scope, budget range, and timeline.
A detailed line-item estimate with allowances and contingencies. You know the number before committing.
We manage all permit applications, engineering consultants, and City approvals — nothing falls through the cracks.
Full-time site supervision, weekly progress updates, and open-book cost tracking throughout.
Structured handover with all documentation, trade warranties, and a 12-month attendance window post-completion.
A full second-storey addition in Don Mills typically costs $350,000–$700,000+ depending on the footprint, finish level, and structural complexity. Partial additions (pop-tops) run $200,000–$400,000. These estimates include all hard construction costs. Soft costs (permits, engineering, architecture) add another $40,000–$80,000 typically. We provide a detailed pre-construction estimate before commitment.
A full second-storey addition in Don Mills typically takes 6–10 months from permit approval to completion. Permit acquisition adds 6–12 weeks. The most disruptive phase — roof removal, structural work, and framing — takes 4–6 weeks. We typically allow families to remain in the lower floor during construction in most cases.
Yes — a second-storey addition requires a building permit, structural engineering drawings, and zoning review for height and setbacks. In some Don Mills properties, particularly those in or near heritage districts, additional heritage review may be required. The City of Toronto permit process for second-storey additions typically takes 6–12 weeks from complete submission. We manage the entire process.
Most Don Mills bungalows can support a second storey addition, but a structural assessment is required to confirm. We evaluate the existing foundation, exterior walls, and floor joist system before finalizing the design. In some cases, beam and post reinforcement is required. We conduct this assessment as part of our pre-construction process at no obligation.
Kopman Build builds second-storey additions across Don Mills and the GTA. One team, full structural management, permit included.
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