Basement & Secondary Unit
Permit Drawings in Ontario
Permit-ready drawing packages for legal basement apartments and secondary suites. We prepare coordinated architectural + structural drawings and coordinate required supporting documents when needed.
Basement Secondary Unit Permits: Clear, Review-Ready Drawing Packages
A legal basement apartment, secondary suite, or second dwelling unit usually needs more than a simple floor plan. Permit review focuses on life-safety items and clear documentation — and delays often happen when details are missing, unclear, or inconsistent.
We prepare the submission documents for your basement permit package, including architectural drawings, structural engineering, and coordinated supporting documents when required for the scope. This can include mechanical/HVAC, plumbing layouts, electrical coordination, fire separation notes, egress information, and other details the municipality may ask to review.
If your project requires structural work, such as new openings, enlarged windows, a separate entrance, underpinning scope, or beam/post changes, we include engineered details so the drawings match the real structure behind the walls.
What Clients Say
Thank you again
my project: attached garage to a bungalow, double car, with a roof back sloped, using a valley system for water drainage.
Thank You Mohammad. We are extremely pleased with the end result.
Punctual, Responsive, Quick, Efficient and Excellent Customer care.
What We Provide
Permit-Ready Drawings
Basement floor plans, sections, construction notes, and details prepared for municipal building permit submission.
Secondary Unit Layout Review
Clear review of the proposed suite layout, including bedrooms, exits, windows, stairs, ceiling heights, and service areas.
Structural Engineering Support
Structural details for new openings, beams, posts, lowered slabs, underpinning review, or other changes when required.
What We Provide for Basement & Secondary Unit Permits
Basement permit applications often involve several small details that can slow down approval if they are not shown clearly. We prepare a coordinated drawing package that explains the proposed work, identifies code-related items, and gives your contractor a clearer path before construction starts.
- Basement permit drawings for finished basements, basement apartments, and legal secondary units
- Existing basement layout review, including room use, stairs, exits, windows, and ceiling height conditions
- Floor plans, construction notes, wall assemblies, fire separation notes, and permit-ready details
- Structural drawings for beams, posts, wall openings, foundation changes, or slab lowering where required
- Coordination notes for mechanical, HVAC, plumbing, and electrical documents when they apply
- Revisions and clarification responses if the municipality requests changes during permit review
If your basement project includes removing walls, enlarging windows, creating a separate entrance, adding bedrooms, or changing the structure, it is better to confirm the permit scope early so the drawings match what the City expects.
Common Items Reviewed for Basement & Secondary Unit Permits
A legal basement apartment is not just about adding a kitchen and bedroom. The space has to be safe, accessible, and properly separated from the rest of the home. We help document these items clearly so your permit submission is easier to understand.
Layout, Egress, and Fire Separation
Secondary unit drawings often need to show bedroom windows, exits, stairs, fire-rated separation, smoke/CO alarm locations, and the relationship between the basement unit and the main dwelling.
- Bedrooms, exits, windows, and stair layout
- Fire separation and safety notes
Structural and Service Coordination
Some basements need more than layout drawings. Enlarged window openings, lowered floors, new beams, separate entrances, plumbing changes, and HVAC changes may need coordinated engineering details.
- Beams, lintels, posts, and openings
- HVAC, plumbing, and electrical coordination
Why Choose GranDesign Engineering
Licensed P.Eng
All drawings stamped and certified by Professional Engineers of Ontario.
Professional Experience (30+ Years)
Over 30 years of experience in all categories of construction projects, from residential to commercial.
Fast Turnaround
Optimized processes for the quickest municipal approval times across the GTA.
Competitive Pricing
Professional engineering services at market-leading rates.
Clear Communication
Regular updates on your permit status with dedicated project managers.
Ontario Expertise
Deep knowledge of municipal review expectations and Ontario Building Code requirements.
Who We Work With
We provide precision structural engineering tailored to the unique needs of property owners and construction professionals.
Homeowners
We help homeowners turn unfinished basements, family spaces, and rental suite ideas into clear, permit-ready drawing packages.
Property Owners
We support owners improving rental properties, investment homes, and long-term family homes with organized basement permit documents.
Contractors & Builders
We prepare accurate plans and engineering notes that reduce back-and-forth, support inspections, and help basement projects stay buildable on site.
Our Services
If you’re planning a basement renovation, basement apartment, or legal secondary unit, we can provide permit-ready drawings, structural design, and coordinated engineering support. You can also explore our other permit drawing and structural engineering services below.
Main Services
Each link opens a dedicated service page with scope details and FAQs.
Basement and second unit projects often connect to larger scopes, including side entrances, structural wall changes, HVAC updates, plumbing work, and electrical coordination. We keep the drawings aligned so the permit package stays consistent.
Additional Coordinated Services
We coordinate supporting documents when they apply to your permit scope.
If your basement or secondary unit permit requires additional documents, we can coordinate them so the package stays consistent from design to permit review.
FAQs
Do I need a permit to finish my basement?
In many cases, yes. If you are creating new rooms, adding bedrooms, changing plumbing, creating a secondary unit, changing structure, or doing work that affects fire safety or exits, the municipality will usually require a building permit. We prepare permit-ready drawings for the proposed basement scope.
What drawings are usually needed for a basement apartment permit?
A typical package may include existing and proposed floor plans, construction notes, fire separation details, window and exit information, stair details, and structural drawings if beams, openings, foundation work, or other structural changes are involved.
Can you help legalize an existing basement apartment?
Yes. We can review the existing layout, identify what needs to be shown for the permit submission, and prepare drawings for the City. If the municipality asks for revisions or clarification related to our drawings, we can update the package.
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