Ontario Design Studio prepares BCIN-certified permit drawings for interior renovations that require a building permit. Not every interior renovation needs a permit - but many common projects do, especially those involving structural changes, plumbing relocation, electrical upgrades, or changes to the layout or use of a space. We help you determine exactly what your project needs and prepare an OBC-compliant package for a smooth approval.
When Does an Interior Renovation Need a Permit?
You generally need a building permit when the work affects structure, safety systems, or how the space is used, including:
- Moving or removing walls - especially load-bearing walls
- Relocating plumbing fixtures in a kitchen or bathroom
- Adding or removing rooms, or changing the floor layout
- Changing the use of a space (for example, garage to living area)
- Upgrading electrical service or panels
- Installing new windows or enlarging window openings in exterior walls
- Converting unfinished space (attic or basement) to habitable space
When You Usually Don't Need a Permit
Purely cosmetic work typically does not require a permit: painting, flooring, trim, cabinet replacement, and swapping fixtures in the same location. When in doubt, ask us first - building without a required permit can trigger a stop-work order and complicate your insurance and resale. Read our complete guide: Do I Need a Permit for My Renovation in Ontario?
Planning an interior renovation?
Ontario Design Studio delivers BCIN-certified, OBC-compliant drawings across Ontario and the GTA. Call 416-558-9607 or request your free quote - most packages are ready in 5–10 business days.
Interior Renovations We Handle
- Kitchen remodels that move walls or relocate plumbing and appliances
- Bathroom additions & relocations with new plumbing runs and ventilation
- Open-concept main floors created by removing a load-bearing wall
- Basement finishing and conversion to habitable or legal apartment space
- Garage conversions to heated living space (change of use)
- Attic and bonus-room conversions with structural and egress upgrades
Our Drawing Package
Every interior renovation package includes existing and proposed floor plans, demolition notes, structural details where required, cross-sections, and the OBC compliance documentation your municipality expects. For projects that remove structure, we coordinate P.Eng structural engineering - beam sizing, load calculations, and temporary shoring - under one package.
Change of Use & Occupancy
Converting a space to a new use - a garage into a family room, or unfinished storage into a bedroom - is one of the most common triggers for a permit. Change-of-use work must bring the space up to code for insulation, heating, ceiling height, egress, and smoke/CO alarms. We identify exactly what your conversion requires so there are no surprises at inspection.
Interior Renovation Permit Costs
Drawing fees for an interior renovation typically range from $800 to $2,500, depending on scope and whether structural engineering is required. This is separate from the municipal permit fee. See our 2026 building permit cost guide for a full breakdown.
Cities We Serve
We prepare interior renovation drawings across the GTA and Ontario, including Toronto, Mississauga, Brampton, Markham, and Vaughan. View all service areas →
Related Resources
- Load-Bearing Wall Removal Permits
- Structural Engineering Drawings
- Building Permit Drawing Cost Guide
- How the Ontario Permit Process Works
- How to Legalize Unpermitted Work in Ontario
Frequently Asked Questions
When does an interior renovation need a building permit in Ontario?
You need a permit when moving or removing walls (especially load-bearing), relocating plumbing fixtures, adding or removing rooms, changing the use of a space, upgrading electrical service, or installing or enlarging windows in exterior walls. Cosmetic changes like painting, flooring, and cabinet replacement typically don't need a permit.
Do I need a permit to renovate a kitchen or bathroom?
If you replace fixtures and finishes in the same locations, usually not. But once you move plumbing, remove or move a wall, add a bathroom, or change the layout, a building permit with drawings is required. We can confirm based on your specific plans.
Do I need a permit to finish my basement?
Finishing a basement into habitable space generally requires a building permit, and creating a legal basement apartment always does. The drawings must address ceiling height, egress, insulation, and smoke/CO alarms.
How much do interior renovation permit drawings cost?
Drawing fees typically range from $800 to $2,500 depending on scope and whether structural engineering is required, separate from the municipal permit fee. Contact us for a free quote on your project.