5 Best Basement Renovations in Toronto (2026)

Royal Work Basement Waterproofing Toronto is a Queens Quay-based waterproofing and drainage contractor, handling exterior and interior waterproofing, foundation repair, underpinning, basement lowering, and sump pump installation across the city. The company's own site lists starting prices from $70 and details City of Toronto rebate programs clients may qualify for. Reviewers describe crews handling century-old foundations as carefully as new builds, and the team is often the first call homeowners make after a basement flood. If your renovation starts with a wet or unfinished space, this is the kind of contractor that gets it dry and structurally sound first.

CD Flood & Sewer Water Damage Cleanup is a Bloor Street restoration company specializing in cleanup after basement floods, sewer backups, and burst pipes. Google lists it as a water damage restoration service and bathroom remodeler. Reviewers consistently name technician Mark as the person who handles jobs directly, from drying out flooded basements to sanitizing and restoring the space afterward. This isn't a full basement-finishing contractor; it's the company you call first when water has already done the damage.

Assured Basements is a North York-based construction company that specializes specifically in basement renovation, remodelling, restoration, and finishing, including legal second-dwelling suites with full permits and inspections. The company runs an in-house design studio, led by designer Alejandra according to one detailed review, and offers financing options for larger projects. One reviewer describes a full legal basement apartment build, complete with new plumbing, electrical, and a separate entrance, passing every city inspection. This is the closest match on our list to a true full-service basement renovation contractor.

The Foundation Kings is a Toronto construction company focused on basement underpinning, foundation work, and building walkout basements. Reviewers describe owner Jamie personally managing projects and coordinating trades so homeowners stay hands-off during the work. One detailed review lists a full underpinning project that added 8-foot ceilings, a new steel beam, waterproofing, and heated floors, expanding the livable footprint of a basement. Like Royal Work, this is a structural specialist rather than a full interior-finishing contractor.

Acon Renovations is a Toronto general renovation contractor covering whole-house projects, kitchens, bathrooms, and basement underpinning and remodelling, based on the Queensway. The company's own site says it's operated in Toronto and the GTA for around 15 years and takes an individual design approach per project. Reviewers describe multi-project relationships; several clients hired Acon two or three separate times for different rooms in the same home, including basement and bathroom work. It's a broader renovation generalist rather than a basement-only specialist.