Mississauga
Headquartered here. Basement finishing, basement apartments, and waterproofing across Port Credit, Streetsville, Lakeview, Erin Mills, Meadowvale, Cooksville, and Churchill Meadows.
Basement renovation in Mississauga →Basement Renovations Near Me — Toronto, Mississauga & the GTA
Looking for a basement renovation contractor near you? Osoba Renos & Design is headquartered in Mississauga and finishes basements daily across Toronto, Etobicoke, Oakville, and the wider GTA. Open-concept layouts, in-law suites, basement apartments, and full waterproofing — completed in three to four weeks with a five-year workmanship warranty and full permit handling.
Where we work
Pick the city closest to you for neighbourhood-specific pricing, permits, and projects.
Toronto
Finished basements, second-suite builds, and waterproofing across the City of Toronto. Full City of Toronto permit handling — drawings, application, plan exam, and inspections.
Basement renovation in Toronto & GTA →Etobicoke
Basement renovations across The Kingsway, Royal York Gardens, Humber Bay Shores, Mimico, Markland Wood, and Princess Anne Manor. About 15–25 minutes from our Mississauga shop.
Basement renovation in Etobicoke →Oakville, Milton & the wider GTA
We have completed basement renovations in Oakville, Milton, Burlington, Vaughan, Thornhill, and Brampton. Send your address for a free in-home estimate.
Get a free in-home estimate →How to choose a basement contractor near you
Five things to verify before you sign anything — applies whether you are in Mississauga, Toronto, Etobicoke, or Oakville.
- 1
Confirm licensing, WSIB, and insurance
Every legitimate basement contractor in Ontario should carry $2M liability insurance and WSIB clearance — and pull electrical (ESA) and plumbing permits where needed. Ask for certificates and verify them before any deposit.
- 2
Ask about permits and inspections
Finished basements require a municipal building permit. A real contractor pulls the permit, prepares drawings, responds to plan exam comments, and coordinates inspections. If a quote skips the permit, it skips the safety review.
- 3
Verify experience with waterproofing
Below-grade rooms in the GTA face moisture, hydrostatic pressure, and temperature swings. Ask how the contractor handles vapour barriers, perimeter drainage, and any past water-incursion history at your address.
- 4
Get an itemised quote
A real quote breaks out framing, drywall, insulation, electrical, plumbing, flooring, painting, and any bathroom/kitchen scope separately — not a single line. Itemised quotes prevent surprise change orders later.
- 5
Confirm timeline and warranty in writing
Basement renovations near you in the GTA typically take 3–4 weeks. Top GTA contractors offer a written workmanship warranty (Osoba: 5 years). Get the start date, expected finish date, and warranty in writing before signing.
For more context, read our deep-dive on how to choose a renovation contractor in Toronto: 7 key questions.
Basement renovation cost & permit by GTA city (2026)
Cost ranges and second-suite eligibility for the GTA cities we cover. Most jurisdictions follow the Ontario Building Code, with city-level variations on permit timing and second-suite rules.
| City | Cost range | Permit authority | Second-suite framework | Notes |
|---|---|---|---|---|
| Mississauga | $100–$150/sq. ft. | City of Mississauga | ARU framework — most lots eligible | Headquartered here. Plan exam typically 3–5 weeks. |
| Toronto | $100–$150/sq. ft. | City of Toronto | Multiplex bylaw — up to 4 units per lot | Plan exam 4–8 weeks. Multiplex zoning expanded 2023. |
| Etobicoke | $100–$150/sq. ft. | City of Toronto | Multiplex bylaw — up to 4 units per lot | Same authority as Toronto. |
| Oakville | $100–$150/sq. ft. | Town of Oakville | ARU framework — most residential lots | Higher average finish level. Plan exam 3–5 weeks. |
| Milton / Burlington | $100–$150/sq. ft. | Town of Milton / City of Burlington | ARU framework | Standard OBC-based requirements. |
| Vaughan / Brampton | $100–$150/sq. ft. | City of Vaughan / City of Brampton | ARU framework | Quoted case-by-case; depends on address. |
Code rules that apply across GTA basement renovations
Four code requirements that show up in every GTA basement renovation — ceiling height, egress, fire separation, and the second-unit framework.
Minimum ceiling height
City of Toronto requires 1.95 m (6'5") clear height across at least 50% of the finished area. Mississauga and Oakville follow similar Ontario Building Code minimums. Older basements often need underpinning or bench-footing if they fall below.
Egress windows
Required for any basement bedroom across all GTA municipalities — minimum 0.35 m² clear opening, sill no higher than 1.5 m above the floor. Cutting into existing foundation costs $2,500–$5,000 and adds 2–3 days.
Fire-rated separation (second suites)
Second-suite builds require a 45-minute or 1-hour fire-rated assembly between units, fire-rated doors, sealed penetrations. Inspected at rough-in and final by the municipal building department.
Second-unit framework
Ontario's Additional Residential Unit (ARU) framework allows second units in most detached, semi-detached, and townhouse lots across the GTA. Toronto added the multiplex bylaw in 2023, allowing up to four units per lot in residential zones.
What's included
Basement Renovation Services
Open-Concept Layout
Create a bright, inviting lower level with smart space planning, wall adjustments, and improved flow.
Permit & Code Compliance Support
Support with permit requirements, drawings, inspections, and licensed trade coordination where required.
Flooring Upgrade
Premium installation of luxury vinyl, engineered hardwood, or tile with proper subfloor preparation.
Framing & Drywall
Complete wall construction, drywall installation, taping, plastering, and finishing for a clean living space.
Insulation & Soundproofing
Thermal and acoustic upgrades for a warmer, quieter, and more comfortable basement.
Lighting & Electrical Upgrades
Pot lights, feature lighting, outlets, switches, and modern electrical improvements coordinated with licensed trades.
Basement Kitchens & Bars
Custom basement kitchens, wet bars, and entertainment areas with cabinetry, countertops, backsplashes, and lighting.
Basement Bathrooms
Beautiful basement bathrooms with waterproofing, premium tilework, modern fixtures, ventilation, and refined finishes.
Laundry Room Renovation
Functional laundry spaces with tile, cabinetry, storage, backsplashes, and clean utility upgrades.
Entertainment & Family Rooms
Comfortable basement living spaces designed for movies, games, hosting, and everyday relaxation.
Lifestyle Rooms
Custom spaces for a home gym, office, studio, playroom, guest room, or hobby room.
Storage Solutions
Built-in closets, shelving, mechanical room storage, and smart solutions to maximize basement space.
Interior Painting
Smooth, moisture-resistant painting for walls, ceilings, trims, and doors.
Floor Leveling
Professional leveling and subfloor preparation for a stable, seamless flooring installation.
Microcement
Modern microcement walls, floors, or feature surfaces with a sleek, waterproof, minimalist finish.
Questions answered
Basement Renovations Near Me — FAQ
How do I find a basement renovation contractor near me in the GTA?
Start with three local options: Google Business Profile (look at the map pack), local subreddits and neighbourhood Facebook groups, and the home renovation directories (HomeStars, Houzz, Renomark). Verify licensing, WSIB clearance, and insurance — then ask each for two recent local references with a finished basement you can call about.
What does a basement renovation near me actually cost in the GTA?
We quote finished basements at $100–$150/sq. ft. because size and scope vary greatly — bathroom additions, second suites, and structural work all affect where you land in that range. We measure on-site and provide a fixed quote tied to your square footage before work begins.
How long does a local basement renovation take?
Three to four weeks for most full basement renovations in the GTA, assuming the scope is set and the permit is in hand. Permit application and plan exam can add 4–8 weeks on the front end, so plan accordingly.
Do I need a building permit for a basement renovation?
Yes — basement finishing requires a municipal building permit, plus electrical (ESA) and plumbing permits when those trades are involved. Ceiling height, egress windows, and fire-separation rules all apply, and second units have additional requirements. We pull all permits as part of every project that requires them.
Can I add a basement apartment as a rental in the GTA?
Yes across all GTA municipalities under Ontario's Additional Residential Unit (ARU) framework — most detached, semi-detached, and townhouse properties are eligible, subject to egress, fire-separation, parking, and minimum-size rules. Toronto goes further with its 2023 multiplex bylaw, legalising up to four units per lot. Each city has its own registration process after the build — Mississauga registers second units with the City; Toronto does it through Municipal Licensing.
What is the difference between waterproofing and basement finishing?
Waterproofing addresses water entry: membrane on the foundation (interior or exterior), perimeter drainage, sump pump, vapour barrier. Finishing is the visible work: framing, drywall, flooring, lighting, paint. If your basement has any history of leaks or efflorescence, waterproof first — finishing over an active leak is throwing money at a problem that will resurface in 6–18 months. We inspect during the in-home visit and only quote finishing once we are confident the slab and walls are dry.
How long does the permit process take across GTA cities?
City of Toronto plan exam is currently 4–8 weeks for typical basement scope, longer for second-suite builds. City of Mississauga, Town of Oakville, and surrounding municipalities run 3–5 weeks for like scope. Add 1–2 weeks for engineer-stamped drawings if structural work (underpinning, beam removal) is involved. We submit on your behalf and respond to plan-exam comments.
Ready for a basement renovation near you?
Send us your address and we will confirm whether you are in our service area and book a free in-home estimate.