Basement Renovation Thornhill

Make your basement feel like a true part of the home. Harmony Basements is a basement renovation company in Thornhill with 20+ years of experience creating spaces for relaxing, working, hosting, or welcoming guests.

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Expect The Absolute Best
“Superior Design • Flawless Execution“

Diego Botia, (B.Arch) Architect

Harmony Basements is a top Thornhill basement renovation contractor with over two decades’ worth of experience. Our Thornhill basement remodels give our clients the basements they’ve always dreamed of having. We provide everything you need, from the planning and design stages to the construction and post-construction phases. With our use of advanced technology and our customer-centric approach, you’re guaranteed a smooth renovation journey with results that surpass all your expectations.

Finished Basement in Thornhill Within 4-6 Weeks

Custom Family Room in Amazing Basement Renovation Project Thornhill

If you’re looking for a reliable company to finish or renovate your basement in the Thornhill area, we can help you achieve your goals. Harmony Basements offers over 15 years of experience working in basements, and we are ready to convert your basement into a beautiful space to enjoy with family and friends.

Within 4-6 weeks of work, you’ll see your basement fully completed.

Free Basement Finishing Estimates in Thornhill

Our company would like to invite you to our office so that we can discuss your project details. What is more, our estimation contractors will visit your home to do measurements so that we can give you ideas to what can be done inside your basement and they will price the job. Our specialty basement services include home offices, gym, theaters, bathrooms, kitchens, saunas, playroom, man cave, wet bars and much more.

Basement Dining Room with Build in Wall Unit and Baseboard Trim - Basement Finishing Thornhill

Basement Renovation Thornhill

Our Thornhill basement renovations are handled by the best designers, architects, technicians, and contractors in the industry. Using innovative technology, we immerse our clients in the remodelling process to give you the best possible experience. Our designers use AutoCAD and VR to give our clients a full tour of their finished basement before construction even begins.

You’re able to see and get a feel for the design up close, ensuring the layout and aesthetic are perfect. When Harmony Basements is in charge of your basement renovation, you can rest assured knowing everything from acquiring permits to safely and efficiently installing HVAC, electrical, and plumbing systems is taken care of.

REQUEST YOUR FREE DESIGN CONSULTATION IN THORNHILL

Improve Home Value with a Thornhill Basement Renovation

The average return on investment (ROI) for a Thornhill basement renovation is 70%. This means, if you were to spend $100,000 on your remodel, you can add $70,000 or more to the resale value of your home. The ROI can reach up to 80% if you are converting your basement into an apartment, adding a full kitchen, or installing a walkout. The following factors affect the ROI:

Livable square footage
Rental potential
Type of materials and finishes
Quality of the design and workmanship

Thornhill Basement Remodelling Ideas

There are a variety of exciting design ideas for a Thornhill basement remodel. No matter what you’re looking for, Harmony Basements can make it happen. Here is a list of remodelling ideas you may be interested in:

A basement gym can be customized to your need and wants. We can install a put in a bathroom with a sauna, soundproof the walls and install wall mounted speakers, include padded flooring and more.

Basement apartments require proper ventilation, adequate privacy, and a balance of natural and artificial lighting. Our team will work with you to create the ideal space for short-term or long-term renters, and/or visiting friends and family.

Basement entertainment rooms can be anything you desire, from bars and theatre rooms to music rooms and dance studios. We can install a full kitchen, a wet bar, a walkout to a patio, and more. You’ll have everything you need to entertain guests, host family game nights, or indulge in your hobbies.

Elevate your basement design with an in-home theatre. Equipped with a snack bar, surround sound, dimmer lights, sound proofed walls, a projector screen and built-in recliners. You won’t ever have to worry about ticket prices or sitting in a crowded theatre again.

Why Choose Harmony Basements as Thornhill Basement Contractors

At Harmony Basements, we make sure you never have to make compromises to your vision. We use all high-quality materials and finishes and put 100% of our effort and dedication into each project we take on.

You can rest with peace of mind knowing all or work is professional-grade and backed by a lifetime warranty. Call or email our team to schedule a free, no-obligation consultation and start planning your basement renovation today.

Custom Basement Bathroom with Sauna - Basement Renovation Thornhill

Custom Wall Unit in Amazing Basement Design by Harmony Basements Thornhill

Harmony Basements – Start your Renovation Today

Harmony Basements handles all portions of your renovation and remodeling project, from design to installation, which eliminates you having to spend time and money on outsourcing trades. We have customers that have gone away on vacation and come back home to a brand new basement a few weeks later. Our reputation is built on quality craftsmanship and trust. Word of mouth has been the core to our business success.

We will create the basement that is tailored to your requirements and fits your budget. Harmony Basement is 10/10 star rated on HomeStars and Houzz, and please preview our portfolio section to see more about the styles of work we offer to our valued customers.

Feel free to give us a call or send us an email with any of your questions and inquiries. Whether you want an extra living space for entertainment or work, Harmony Basements offers full basements solutions for homeowners in Thornhill Ontario and the Greater Toronto Area.

Call Us

Our customer service representatives are ready to assist you. Call us now 1-905-669-9039. Basements are all we do!

Open Space Amazing Basement Design Thornhill

Basement Finishing Project Custom Home Gym Thornhill

View our latest basement renovations

Environmentally-Friendly Basement Renovation Experts in Toronto and the GTA

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 Thornhill

Expect The Absolute Best
“Superior Design • Flawless Execution“

Finished Basement in Thornhill Within 4-6 Weeks

Free Basement Finishing Estimates in Thornhill

Basement Renovation Thornhill

Improve Home Value with a Thornhill Basement Renovation

Thornhill Basement Remodelling Ideas

Why Choose Harmony Basements as Thornhill Basement Contractors

Harmony Basements – Start your Renovation Today

Environmentally-Friendly Basement Renovation Experts in Toronto and the GTA

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?