Basement Renovation St. Catharines

Give your home a more complete feel with a basement planned for real life. With experienced basement renovation contractors in St. Catharines, Harmony Basements creates spaces for relaxing, hosting, working, or growing families.

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Expect The Absolute Best
“Superior Design • Flawless Execution“

Diego Botia, (B.Arch) Architect

Harmony Basements is a leading St. Catharines basement renovation and finishing contractors with 20+ years of experience. When you remodel your basement with our team, we guarantee that you’ll have a more functional space for you and your family to use. Our specialty is high quality, efficient, and customer-first basement remodels. We use cutting-edge technology to give our clients the best renovation experience possible. Ensuring you have the design, build, and finish you’ve always wanted for your basement. When you partner with us, you’re guaranteed to work with the best.

Full Basement Renovations in St. Catharines

Our St. Catharines basement renovation services provide you with everything you need in one place. We have an in-house design team, architects, technicians, project managers, and construction workers. There’s no aspect of the project that we can’t handle. Our designers use VR technology to give you a virtual tour of your basement before finalizing the design.

Our project managers keep the renovation on schedule and within budget, all while making sure you stay informed at each stage. We also have one of the best installation teams who never deliver anything less than exceptional workmanship.

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Modern Family Room Design in Custom Basement Renovation Woodbridge

Finished Basement Within 4-6 Weeks

On a tight schedule? We can have your basement live-in ready within 4 to 6 weeks. This includes all phases: planning, financing, construction, and decorating. You will receive a free consultation where we give you an estimate. We also provide a flexible financing plan, where you can set up a payment plan for your finished basement.

You’ll also be able to see the finished product before we hit the ground running. Trust us when we tell you that it looks like the final result. This is all thanks to our Virtual Reality Design software.

Improve Home Value with a Basement Renovation St. Catherines

A St. Catharines basement remodel stands to improve your home’s value by approximately 70% of the renovation costs. This means that a remodel that costs $100,000 could increase your home’s value by $70,000 or more.

The addition of a basement kitchen, bathrooms, or a full basement apartment can add 80% or more onto the overall value of your property. A finished basement of any kind is also a very attractive feature to prospective home buyers.

Basements Built with Confidence

Harmony Basements has a team of dedicated and passionate employees behind the name who want nothing more than to see a smile on your face when you see your new basement. Your vision is our vision too. You also have control over the entire process and are able to monitor and review each stage.

We take pride in taking a sustainable stand in the construction industry. All our products are clean and eco-friendly. They are also weather resistant. So, not only will your basement be healthier, but it will also be protected from the weather and elements.

Basement Remodeling Ideas

A finished basement gives you plenty of new usable space. You can get creative and create the hobby, entertainment, or living space you’ve always dreamed of having. As top St. Catharines basement renovation contractors, we can deliver any of the following basement remodel ideas:

A basement gym needs proper ventilation and lighting. Some of the features you an add to a basement gym are soundproofed walls, built-in speakers, padded flooring, and a sauna. We can also install a wet bar for convenient access to drinks and snacks.

A basement apartment can be a great source of a secondary income. The space can be rented out part time or full time depending on your preferences. You could also use the apartment for visiting family and friends, or for live-in relatives.

Entertain guests with a full basement kitchen, dinning, and lounge area. Basements also make the perfect family entertainment rooms. We can design and build a game room, theatre, and wet bar for fun family game nights.

An in-home theatre can be big or small and stylized anyway you wish. Add a flat screen or projector, a snack bar or a full bar, and so much more. Set the tone with dimmable lighting, wall-mounted speakers in every corner, and big comfy chairs with cup holders and eating trays.

Why Choose Harmony Basement as Basement Contractors

Basement renovations are significant projects. They need to be handled by qualified and skilled contractors who understand the waterproofing, ventilation, and structural needs of a basement.

That’s why you should call Harmony Basements. Begin planning your St. Catharines basement remodel with us by calling or emailing our team today.

Our Work

VIEW OUR FULL BASEMENT PORTFOLIO HERE

Real Reviews

That speak louder than words

My wife and I set out to find a contractor to completely gut and transform our basement into a fully functional suite for our daughter, her boyfriend, his 4-year-old son, and their soon-to-arrive baby.Our requirements were strict: we needed a family room, a kitchen, a 3-piece bathroom, and three bedrooms. Given the limited square footage and the unusual foundation layout of our basement, we knew this would be a major challenge. We needed someone highly creative, experienced, and willing to think outside the box.Most of the contractors we met came in, took basic measurements with tape or a laser, briefly listened to our needs, and quickly quoted us. Almost all of them said that fitting a 3-piece bath and a family room was possible, but having three bedrooms as well was “virtually impossible.” That was until we met Diego from Harmony Basements.From the moment Diego walked in, it felt different. He carefully listened to everything we wanted, then proceeded to take detailed measurements of every part of the basement. That very same night, he sat down and designed a scaled layout complete with a virtual 3D walkthrough that showed us exactly what we had envisioned and more. Diego is an absolute wizard at maximizing every square inch of space. He spent over three hours with us that evening.Then came the question all homeowners dread: “When can you start, and how long will it take?” Without hesitation, Diego confidently said he could start within the week and finish in four to six weeks. He explained that he had dedicated teams for every trade and that a project manager would be assigned to oversee the entire build.When Diego left, my wife and I just looked at each other in disbelief. It felt too good to be true.But Diego kept his word. Within days, we received a clear, detailed, and structured work schedule. Honestly, after receiving such a “Rolls-Royce” level of service in our first meeting, we braced ourselves for a shocking price. To our surprise and relief, the cost was well within our budget.One thing worth noting: Harmony Basements was the only company that included key finishes: bathroom vanity, toilet, plumbing fixtures, kitchen cabinets, sink, and faucet... all in the base quote. Other contractors excluded these or listed them as upgrades.After signing, we were invited to their showroom to select paint colors, kitchen cabinet styles, bathroom tiles, plumbing fixtures, trim details, and more. It felt like designing a brand-new home.Throughout the project, we made a few changes to the layout. Diego and our assigned project manager, Roy, handled all of them without hesitation. In fact, Diego made some excellent suggestions that we happily adopted, such as relocating the entire furnace and ducts to improve the layout. Communication was consistent, and the entire team was professional, respectful, and clearly passionate about their work.Diego, Roy, and the talented crew completed everything exactly on schedule, no delays and no excuses.The finished result is nothing short of spectacular. We’re still amazed at how they managed to turn our challenging basement into a beautiful, spacious, and practical suite with a cozy family room, a large bathroom, and three bedrooms with proper closets. The attention to detail and craftsmanship truly stand out.The process was smooth and stress-free. The team worked diligently, five to six days a week, allowing our daughter and her family to move in earlier than expected.It’s also worth mentioning that Diego doesn’t just do basements. He handles full home renovations of all kinds.. and after this experience, we wouldn’t trust anyone else.If you're looking for a one-stop shop with a professional, trustworthy contractor who delivers exceptional results at a fair price, look no further. Choose Diego and Harmony Basements.. you’ll be glad you did!

James Johnson

14:02 07 Oct 25

My wife and I set out to find a contractor to completely gut and transform our basement into a fully functional suite for our daughter, her boyfriend, his 4-year-old son, and their soon-to-arrive baby.Our requirements were strict—we needed a family room, a kitchen, a 3-piece bathroom, and three bedrooms. Given the limited square footage and our basement's unusual foundation layout, we knew this would be a major challenge. We needed someone highly creative, experienced, and willing to think outside the box.Most of the contractors we met came in, took basic measurements with tape or a laser, briefly listened to our needs, and quickly quoted us. Almost all of them said that fitting a 3-piece bath and a family room was possible, but having three bedrooms as well? "Virtually impossible"—until we met Diego from **Harmony Basements**.From the moment Diego walked in, it was different. He carefully listened to everything we wanted, then proceeded to take detailed measurements of every part of the basement. That very same night, he sat down and designed a scaled layout complete with a virtual 3D walkthrough that showed us exactly what we had envisioned—and more. Diego is an absolute wizard at maximizing every square inch of space. He spent over three hours with us that evening!Then came the question all homeowners dread: *"When can you start, and how long will it take?"* Without hesitation, Diego confidently said he could start within the week and finish in 4–6 weeks. He explained that he had dedicated teams for every trade and that a project manager would be assigned to oversee the entire build.When Diego left, my wife and I just looked at each other in disbelief—this felt too good to be true.But Diego kept his word. Within days, we received a clear, detailed, and structured work schedule. Honestly, after receiving such a “Rolls-Royce” level of service in our first meeting, we braced ourselves for a shocking price. To our surprise and relief, the cost was well within our budget.One thing worth noting: **Harmony Basements was the only company** that included key finishes—bathroom vanity, toilet, plumbing fixtures, kitchen cabinets, sink, and faucet—all in the base quote. Other contractors excluded these or listed them as upgrades.After signing, we were invited to their showroom to select paint colors, kitchen cabinet styles, bathroom tiles, plumbing fixtures, trim details, and more. It felt like designing a brand-new home!Throughout the project, we made a few changes to the layout. Diego and our assigned project manager Roy handled all of them without hesitation. In fact, Diego made some excellent suggestions that we happily adopted, like relocating the entire furnace and ducts to improve the layout. Communication was consistent, and the entire team was professional, respectful, and clearly passionate about their work.Diego, Roy, and the talented crew completed everything exactly on schedule—no delays, no excuses.The finished result is nothing short of spectacular. We’re still amazed at how they managed to turn our challenging basement into a beautiful, spacious, and practical suite with a cozy family room, a large bathroom, and three bedrooms with proper closets. The attention to detail and craftsmanship really stand out.The process was smooth and stress-free. The team worked diligently—5 to 6 days a week—allowing our daughter and her family to move in earlier than expected.It’s also worth mentioning: **Diego doesn’t just do basements**. He handles full home renovations of all kinds—and after this experience, we wouldn’t trust anyone else.If you're looking for a one-stop shop with a professional, trustworthy contractor who delivers exceptional results at a fair price, **look no further**—**choose Diego and Harmony Basements**. You’ll be glad you did!Check out the attached pictures starting from the initial basement through demolition to completion!

James Johnson

21:41 02 Sep 25

This is the second basement project completed with Harmony Basements and we are thrilled with the results. Diego and his team were professional, courteous, friendly and consulted us through the project. Workmanship and details were excellent. Diego helped us navigate through some material supply shortages, common these days, to deliver a top notch design that was on time and budget! Looking forward to enjoying our basement for many years to come. Thanks again!

Dan M

18:18 01 Sep 25

Three words to summarize Harmony Basements: fantastic and highly recommended.We had been considering finishing our basement for some time and spoke with a few contractors, with Harmony being one of them. From the very first meeting with Diego, we felt confident. He came to our unfinished basement, listened to our ideas, and surprised us by quickly preparing a detailed architectural 3D rendering walkthrough of what the finished space could look like, along with a clear price and timeline.Once we moved forward, everything fell into place seamlessly. The process was very organized and the communication was always clear. Diego’s project manager, Roy, took over once construction started, and the team worked efficiently and professionally. Diego had promised the work would be done in six weeks, and they actually finished two days ahead of schedule.I didn’t have any referral or recommendation for Harmony, but I trusted my gut after meeting Diego, and I’m very glad I did. This team truly delivered beyond expectations.If you are looking for a contractor who respects timelines, produces excellent results, and runs projects with professionalism, I highly recommend Harmony Basements.

Rajni Radja

00:48 25 Aug 25

From the moment I sat down with Diego , I knew that he was passionate about what he does and that my basement Reno was in good hands.He has surrounded himself with an impeccable team and the work they do is something that will truly amaze you .Where other companies were requiring that i take care of the permits, Diego put my fears at ease and handled it all , so that I wouldn’t have to.From moving ducts around so that I may have a cleaner ceiling look to extending my accent wall so that the tv does not cover it all, Diego really makes sure that you will be completely satisfied with the finished product.We couldn’t be happier with how our basement came out.A huge Thank You to Diego and the entire Harmony Basements Family for making this project so easy on us and for having us grin from ear to ear with the finished product.

Demetrios B

10:30 07 Aug 25

In 2024, they renovated our 2,000 sq. ft. space into a beautiful suite with a bedroom, walk-in closet, full bath, studio/gym, large storage, living-dining area, laundry, and direct garage access—all within six weeks, as promised.From the start, architect-owner Diego impressed us. He spent hours designing our layout, offered smart advice on function and budget, and delivered a 3D design that fit our lifestyle. His attention to detail—from switch placements to structural integrity—shows his professionalism and experience.A special thank you Roy, the site manager! He far exceeded our expectations; pleasant, knowledgeable, respectful, experienced, and structurally sound. He was very patient with our questions about minor details such as heights of towel rods and mirror! Roy went out of his way to personally make the project successful! Our confidence in Harmony was 100% enhanced by Roy's almost daily presence and his long hours to meet the timeline.Thanks as well to:- Arturo for precise framing and perfect bulkheads and drywalling- Jimmy for high-quality painting—even on weekends- Sasha for her reliable daily coordination- Stephany, our designer, for her current and patient design choicesThe entire crew was respectful, timely, tidy, and efficient. They cleaned up daily, and even hired professional cleaners for the final day—something other companies don’t provide.Diego runs Harmony with honesty, transparency, and no surprises or extras. He even followed up personally on a kitchen cabinet issue within 24 hours. We never once had to chase them after payment, and he stayed just as helpful after the project ended.I’m 110% satisfied with the results of this project. From the design build to the handing over, we were totally happy we picked Harmony for the excellent quality of their work. We will definitely rehire them in the future for any renovation needs.

Katherine Gan

20:59 29 Jun 25

Harmony Basements understands what it means to exceed expectations. We asked them to come and quote us for completely finishing our basement that included a wet bar, 3 piece bath, and podcast studio. Other contractors that we asked for quotes provided one after a 30 minute inspection of the house.Diego spent approximately 3 hours working on the quote at our home, which resulted in a 3D walkthrough and 3 different layout options of what the finished product would look like. His attention to detail, and work put into the quote, as well as his willingness to be flexible on price gave us the confidence to go with him and his team.Add to that, that we had a very tight timeline of exactly 6 weeks, his team of specialized contractors put in the extra hours and weekends to ensure that the project was completed with time to SPARE which served to help us immensely in getting our studio ready for broadcast.There were issues with getting the permit and later some electrical issues, which Diego and his team addressed promptly without having to chase them which was very refreshing to see.In the end, we are 100% satisfied with the result of the build. From design, to the friendliness of his people, to the quality and speed of the work, you would be missing out if you did NOT use Harmony Basements for your needs.They are truly in a class all on their own.

Ryan Davies

13:44 05 Jun 25

We loved working with Diego, Roy and everyone from Harmony Basements. From our initial meeting with Diego it was clear who we were going to choose for our basement renovation. Several times I thought we may have encountered something that would stretch our initial timeline, but if longer days were required then that’s what happened to keep it on time. Always available, clear communication and planning, good people. You won’t be disappointed choosing Harmony for your project.

Taylor Brown

12:30 05 Jun 25

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Limited-Time Exclusive Offer

While Others Cut Corners, We Raise Standards

Free Building Permit for personal use basements

Quality Over Gimmicks

We don’t play the “lowest quote” game, we deliver superior value from day one.

Transparent, Itemized Pricing

No guesswork or hidden fees—see exactly what each line costs and why it’s there.

Free Building Permit

To protect your investment, we handle all architectural drawings, submission, & inspections – at no extra cost.

3D Architectural Design + Virtual Reality Tour

Test-drive your basement design with a realistic 3D walk-through. Powered by technology brought straight to your home.

Book your design consultation now and the building permit service is on us ($2,825.00+ value)

Premium Upgrades – Now Standard

Upgrade:	What you get:
Subfloor System	Low-profile, mould-resistant, fully waterproof. Built-in airflow & insulation.
GRANDEUR® Luxury Vinyl Plank	Choose 33 flood-proof colours – Integrated underlay blocks mould & mildew.
100 % Matching Vinyl Stair Capping	Seamless look from floor to steps—no fragile hardwood stain guessing games.
Waterproof, Mould-Free Envelope	Engineered system that protects your investment from the ground up.

High-Quality Finishes aren’t Extras – They’re Our Baseline.

Request your consultation today
and lock in the current Bonus before it’s gone

Basement Renovation St. Catharines

Expect The Absolute Best
“Superior Design • Flawless Execution“

Full Basement Renovations in St. Catharines

Finished Basement Within 4-6 Weeks

Improve Home Value with a Basement Renovation St. Catherines

Basements Built with Confidence

Basement Remodeling Ideas

Why Choose Harmony Basement as Basement Contractors

Our Work

DIEGO BOTIA

Book Your Private Showroom Visit with a True Basement & Construction Expert

See why families across Ontario continue to choose Harmony Basements year after year, since 2014

Real Reviews

That speak louder than words

A Great Basement Renovation Begins With A Great Design

Are You Ready To Be WOWED?