Building Construction Services in Ontario: Custom Homes, Additions & Renovations
A good building project depends on more than good drawings. It also needs a skilled crew, a realistic schedule and someone who keeps everything organized from the first day on site. For this reason, Proventa Construction provides complete building construction services across Ontario. Our work covers custom homes, additions, basement suites, renovations and light commercial interiors. Whether you are starting from an empty lot or an older house that needs a major update, we manage the project from planning to final inspection.
In addition, we are a design-build company, so the same team that prepares your architectural plans and permits also does the construction. As a result, there are fewer handoffs, fewer misunderstandings and clearer pricing. Many homeowners find this far easier than coordinating a designer, a permit consultant and a contractor on their own. With us, however, you deal with one team that is accountable for the whole job.
Custom Home Construction
First, we build the home you designed, from excavation and foundations to framing, mechanical systems and finishes. Because we follow the approved drawings closely, the finished house matches the plan. We also flag practical issues early, so that small problems never grow into costly changes.
Additions & Structural Work
Adding space to an existing home takes careful planning. Therefore, we assess the current structure, tie the new work into it properly and arrange engineered solutions where needed. Whether it is a rear addition or a second storey, we aim to make the result look like it was always part of the house.
Basement Suites & Legal Conversions
A finished basement can add living space or rental income. However, a legal second unit has to meet Ontario Building Code requirements for egress, fire separation, ceiling height and ventilation. For that reason, we build to the permit drawings and coordinate the inspections needed to sign off the unit.
Renovations & Interior Remodels
From kitchens and bathrooms to whole-home updates, we handle the demolition, structural changes, trades and finishing. Meanwhile, we keep you informed about progress, decisions and costs, so there are no surprises along the way.
Our Core Building Construction Services
Overall, we offer a full range of construction services for homeowners, landlords and small business owners.
New Home & Infill Construction
Complete builds for single-family homes on vacant lots, teardown sites and infill properties. Moreover, each project is planned around your budget and schedule.
Home Additions & Second Storeys
Rear, side and vertical additions built to match your existing home. In addition, we coordinate structural reinforcement and utility connections.
Basement Finishing & Underpinning Coordination
Basement finishing, waterproofing coordination and ceiling height solutions. Furthermore, we work with specialists when underpinning is required.
Kitchen & Bathroom Renovations
Full remodels, including layout changes, plumbing, electrical, cabinetry and tile. As a result, you get a finished space that works well and lasts.
Structural Wall Removal & Open Concept Conversions
Safe removal of load-bearing walls with properly sized beams and posts. Where the Building Code requires it, we also arrange engineer-stamped details.
Garages, Decks & Porches
Attached and detached garages, raised decks and covered porches. Although they look simple, these projects often need permits and solid foundations.
Garden Suites & Accessory Dwellings
Detached units for family or rental use, built where zoning and servicing allow. Before we start, we check these requirements carefully.
Commercial Interior Fit-Outs
Office, retail and service spaces built to code and to your brand. Likewise, we handle change-of-use requirements when they apply.
How Our Construction Process Works
Because clear communication prevents most project problems, we follow a simple step-by-step process.
1. Consultation & Site Review
First, we discuss your goals, visit the property and review any existing drawings. Then we outline what is realistic for your budget and timeline.
2. Design & Permits
Next, our team prepares the architectural drawings and building permit application. Because we handle this ourselves, the plans are practical to build.
3. Detailed Pricing & Scheduling
Once the drawings are ready, we provide a clear scope of work, pricing and schedule. As a result, you know what to expect before work begins.
4. Construction & Site Management
Then our crew and trades start work. Throughout the build, we manage inspections, deliveries and updates, and we deal with any issues that come up.
5. Final Inspection & Handover
Finally, we complete a walkthrough with you and close out the required inspections. Afterwards, we remain available for any follow-up questions.
Why Choose Proventa for Your Building Project?
Building Construction Services Near You
We build for homeowners across Ontario, and we understand the requirements of each city.
Construction conditions vary a great deal from one community to the next. For example, northern projects must deal with rock and heavy snow loads. Similarly, lakeside and river properties often involve conservation authority approvals. To see how we help locally, visit our pages for Mississauga, Toronto, Hamilton, London, Windsor, Oshawa, Sudbury and Sault Ste. Marie, among other communities.
Frequently Asked Questions: Building Construction
Below, you will find straight answers to common questions about hiring a builder and planning a construction project.
What is design-build construction?
In a design-build project, one company handles both the design and the construction. As a result, you have a single point of contact and a single contract for the whole job. In contrast, the traditional approach involves hiring a designer first and then a separate contractor, which can lead to miscommunication and budget gaps.
How much does it cost to build or renovate a home in Ontario?
Costs depend on size, finishes, site conditions and the scope of the work, so there is no single figure that applies to every project. However, we can give a realistic estimate once we understand your plans and have reviewed the property. In addition, the more complete your drawings are, the more accurate the pricing will be.
Do I need a building permit before construction starts?
In most cases, yes. New buildings, additions, structural changes, secondary suites and many decks all need a permit. On the other hand, small accessory buildings under 10 square metres (about 107 sq. ft.) are usually exempt from a building permit, although they still have to meet zoning rules. Since we also prepare the drawings, we can handle the application for you.
How long does a construction project take?
The timeline depends on the project. A basement renovation may take a few weeks to a couple of months, while a custom home usually takes many months. Besides the build itself, you should allow time for design and permit approval, and for ordering long-lead materials. We provide a schedule before work begins and update you if anything changes.
Can you build a legal basement apartment in my house?
Often, yes. First, we check that your property and house can accommodate a second unit under zoning and Building Code rules. Then we prepare the drawings, obtain the permit and build the unit to code. Finally, we coordinate the inspections so the suite is properly approved.
Can I stay in my home during a renovation?
Sometimes. Small or phased projects, such as a basement or a single bathroom, often allow you to stay. However, a whole-home renovation or a project that affects kitchens, heating or water may make living at home difficult. We talk through this with you during planning so you can prepare.
What happens if the plans change during construction?
Changes do happen, especially on renovations where hidden conditions appear once walls are opened. Therefore, we explain the change, its cost and its effect on the schedule before any work proceeds. That way, you stay in control of the budget at every stage.
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Verified Customer Reviews
Proventa Construction transformed our unfinished basement in Oakville into a comfortable, modern living space. The… recessed lighting brightens the rooms, and the flooring, drywall and painting give everything a clean, finished look. We especially appreciate how well the layout works for our family. Very happy with our basement renovation.
We had a great experience with Proventa Construction for our basement finishing project. They helped us make better use… of the space with a welcoming recreation area, practical storage and modern lighting. The neat trim, smooth walls and attention to the smaller details made a big difference. Our basement finally feels like part of our home.
Proventa Construction Inc. transformed our outdated 1990s kitchen into a stunning open-concept dream space. They… removed a load-bearing wall, installed custom cabinetry, and fitted gorgeous quartz countertops. The project leadership was top-notch—they kept everything clean, organised, and strictly on schedule. The attention to detail on the tile backsplash and lighting upgrades made a huge difference. Highly recommended for any major kitchen remodel!
Really happy with how our basement turned out. Proventa Construction did a fantastic job transforming it into a… beautiful, fully finished legal basement with a modern island kitchen, stylish cabinets, and elegant countertops. The whole space looks amazing and feels like a separate home. Highly recommend Proventa Construction for legal basement renovations and home remodeling in the GTA!
We hired Proventa Construction to build a below-grade entrance for our basement apartment. The work included… excavation, concrete steps, retaining walls, and drainage. The team explained the process clearly and kept us updated throughout.
We recently hired Proventa Construction to renovate our kitchen, bathroom, and basement all at once. Honestly, taking… on three major spaces had us incredibly stressed, but the team made the entire process so much easier. They were straightforward with pricing, transparent about the timeline, and actually showed up when they said they would. The craftsmanship is excellent—the kitchen is beautiful and functional, the bathroom feels like a proper upgrade, and the basement went from a dusty storage zone to a bright space we actually use every day. There were a couple of minor material delays along the way, but they communicated immediately and sorted it out without dragging their feet. If you want a dependable crew in the Toronto area that does quality work and respects your home, I highly recommend them.
We recently hired Proventa Construction for a complete overhaul of both our kitchen and bathroom, and honestly, they… knocked it out of the park. From our very first meeting, the team felt more like good neighbors who genuinely cared about our house rather than just another contractor. They really listened to our vision (and our budget!) and turned what could have been a super stressful process into a really exciting project. The craftsmanship is top-tier. Our kitchen is now the ultimate gathering spot—functional, beautiful, and the custom finishes are just stunning. And the bathroom? It honestly feels like a boutique hotel spa now. What really stood out to us was their communication. They kept us in the loop every step of the way, showed up on time, and left the place spotless at the end of every work day. In true Canadian fashion, they were polite, professional, and just a real pleasure to have around. If you are looking to renovate and want a team you can actually trust to do an incredible job, look no further than Proventa. We couldn't be happier with how everything turned out. Thank you guys so much!
Proventa Construction did an excellent job finishing townhouse basement in Mississauga. The team provided honest… guidance, practical suggestions, and quality workmanship. Communication was clear throughout, and the finished basement feels comfortable and inviting. Highly recommend Proventa Construction for basement renovations in Mississauga.
We recently worked with Proventa Construction to renovate our basement, and they were incredible. They turned a dark,… unfinished space into a beautiful, bright, and comfortable extension of our home. From start to finish, the team was transparent, respectful, and genuinely cared about the quality of their work. If you're looking for trustworthy people who do amazing work, we highly recommend Proventa!
Honestly, we couldn't be happier with the job Proventa Construction did on our kitchen and basement! From day one, the… guys were super professional, completely reliable, and just all-around great people to have around the house. They turned our kitchen into an absolute dream and made the basement so cozy for the family. Their attention to detail is incredible, the pricing was totally fair with zero surprises, and they made the whole project completely stress-free. If you're looking to upgrade your place, we highly recommend them—they truly went above and beyond!
Our City-Wise Architectural & Permit Services
Proventa Construction provides comprehensive, end-to-end architectural drafting, structural design, and municipal permit clearance services across Ontario. We tailor each project to local zoning bylaws and Ontario Building Code standards to ensure seamless approvals and flawless project execution.
Explore our specialized local design and permitting solutions in your city:

