Adding a second storey is one of the most transformative renovations you can make to an Ontario home. It creates major square footage, boosts property value, and allows families to stay in their neighbourhood while expanding their living space.

But homeowners often underestimate how complex second-storey additions truly are.

Common Misconceptions About Second Storey Additions

Many homeowners begin with assumptions such as:

  • “I already have drawings, so I’m ready for a permit.”

  • “The structure can likely support a second level without major changes.”

  • “It’s mostly cosmetic—just raising the roof.”

  • “Any contractor or designer can prepare the drawings.”

However, adding a second storey triggers some of the most significant structural, zoning, and Ontario Building Code (OBC) requirements of any residential project. These projects frequently involve:

  • Structural load path redesign

  • Reinforcement of foundation or existing walls

  • Cathedral ceilings or dormers

  • Height restrictions and zoning obstacles

  • Complex roof restructuring

  • Fire separation requirements

  • Detailed engineered drawings

  • Design changes to ensure future additions are possible

This is why a second storey addition requires specialized permit drawings, produced by a design firm deeply familiar with structural engineering, OBC Part 9, zoning bylaws, and multi-phase planning.

Example: Second Storey Addition in Kitchener Designed by MW Drafting & Design

second storey addition Kitchener

Rendering of proposed second storey addition in Kitchener, Ontario by MW Drafting & Design.

When a homeowner in Kitchener envisioned adding a second storey, they approached MW Drafting & Design to turn their concept into a fully engineered, code-compliant, and build-ready solution.

The project involved major structural modifications, including:

  • Raising the roof

  • Designing cathedral ceilings

  • Adding dormers

  • Managing multiple structural point loads

  • Ensuring future expansions could be integrated into the current design

Here’s how MW Drafting & Design transformed a conceptual idea into a smooth, compliant, and construction-ready addition.

Biggest Challenges in Adding a Second Storey to an Existing Home

1. Complex Structural Engineering Requirements

Adding an upper level changes how loads transfer through the house. This often requires:

  • Engineered steel beams

  • New point load paths

  • Reinforced floors or walls

  • Roof removal and rebuilding

  • Engineering stamps for structural components

In this example, the design required precise tracking of every structural point load, ensuring both immediate and long-term stability.

2. Adjusting a Preliminary Homeowner Design to Meet Code

The homeowner had initial plans, but many elements needed changes to meet:

  • Zoning regulations

  • Height limitations

  • Ontario Building Code structural requirements

  • Kitchener bylaws

MW Drafting recreated the home in a full 3D Revit model, visually walking the homeowner through issues and presenting an improved, compliant design.

3. Planning for Future Additions

The homeowner wanted future phases, so MW Drafting built these into the engineering and roof design.

This avoided the need for costly structural changes later.

How MW Drafting & Design Creates BCIN Permit-Ready Drawings for Second Storey Additions

MW Drafting uses a proven system for second-storey additions throughout Ontario:

Comprehensive Site & Zoning Review

Every addition starts with a zoning check to confirm:

  • Maximum building height

  • Setback requirements

  • Lot coverage

  • Floor space ratio

  • Access and fire safety requirements

Ontario Building Code Compliance

All structural and architectural drawings follow the OBC. This ensures the drawings meet the standards required for:

  • Structural capacity

  • Fire safety

  • Means of egress

  • Guarding and fall protection

  • Energy efficiency

  • Roof and floor loading

Engineered Structural Design

MW Drafting & Design uses in-house engineering software to produce:

  • Engineered beams

  • Load-bearing wall specifications

  • Point load calculations

  • Roof truss modifications

  • Foundation reinforcement recommendations

All structural elements are stamped when required.

Full 3D Revit Modelling for Accuracy

This allows the team to:

  • Identify structural conflicts early

  • Visualize the new second level

  • Explain code issues clearly

  • Improve constructibility

Permit-Ready Drawing Package

A second-storey addition permit set includes:

  • Existing & proposed floor plans

  • Roof plans

  • Elevations

  • Building sections

  • Structural layouts

  • Framing plans

  • HVAC and mechanical details (as needed)

  • OBC matrix

  • Site plan

  • Engineering documentation

These documents ensure your contractor has exactly what they need for pricing and seamless construction.

Benefits of Proper BCIN Permit Drawings for Second Storey Additions

1. Faster Permit Approval

Clear, compliant drawings reduce revision cycles with the city.

2. Accurate Construction Pricing

Contractors can quote confidently with engineered, detailed drawings.

3. Avoiding On-Site Delays or Surprises

The more complete the drawings, the smoother the build.

4. Long-Term Structural Security

Engineering ensures your home can safely support the new load.

5. Better Design Control

3D modeling allows homeowners to visualize the addition before construction begins.

In the above example, MW Drafting’s drawings provided everything the contractor needed for a seamless build, saving time and reducing errors.

Why MW Drafting & Design Is the Best Choice for Second Storey Addition Drawings in Ontario

MW Drafting provides:

  • BCIN-certified, Ontario-compliant architectural drawings

  • In-house engineering for complete structural design

  • 3D Revit modelling for accuracy and clear visualization

  • Experience completing second-storey additions across Ontario

  • A collaborative approach with contractors and homeowners

  • Expert permit submission support

Planning a Second Storey Addition in Ontario? Start With a Free Discovery Call

MW Drafting & Design helps homeowners, investors, and contractors bring second-storey additions to life with clarity, structural engineering, Ontario Building Code expertise and permit-ready precision. Click here to book a free discovery call to get started right away!

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