This guide compares 19 basement renovation companies serving Ottawa. The featured shortlist includes Vanguard Contracting, Select Urban General Contractors, and Ottawa Finished Basements. Listings claimed by their owner appear first; all other positions follow the published rating methodology. 18 carry a sourced public rating, averaging 4.9 stars; the highest-rated is AMA United Company Inc. at 5.0 stars from 180 Google reviews.
The best basement renovation companies in Ottawa turn an unfinished basement into real living space, managing framing, insulation, drywall, flooring, electrical, and often waterproofing under one roof. It is one of the highest-return spaces to finish in an Ottawa home, but low ceilings, moisture, and egress rules make it worth hiring a specialist. The companies below cover basement finishing, full basement renovations, and legal secondary suites across the city. Each is a real Ottawa business with public reviews you can read, so you can compare past basements, project management, and pricing before you commit.
Also covers: Basement renovation · Basement finishing · Finished basement · Basement contractor · Secondary suite
Featured professionals
A focused Ottawa shortlist. Listings claimed by their owner appear first; all other positions follow our published rating methodology.
Listings claimed by their owner appear first. All other positions follow the selected sort.
FeaturedKanata +7
5.0(84)on GoogleChecked Aug 2026Basement FinishingVanguard Contracting is an Ottawa basement renovation company serving homeowners across the city, offering basement finishing and basement renovation. It holds a 5.0-star average across 82 Google reviews.
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FeaturedNepean +6
5.0(67)on GoogleChecked Aug 2026General ContractorsOttawa residential renovation contractor offering full-home, kitchen, bathroom, and basement renovations plus additions, coach houses, and accessible renovations with in-house design and 3D planning. BBB-accredited with an A+ rating and serves neighbourhoods across the city.
View Select Urban General Contractors
Kanata +7
5.0(30)on GoogleChecked Jul 2026Basement FinishingOttawa company specializing in basement finishing and renovations, transforming unfinished basements into living space.
View Ottawa Finished Basements
ClaimedKanata +7
4.9(29)on TrustedProsChecked Jul 2026General ContractorsFamily-owned Ottawa home renovation contractor operating since 2009, offering kitchens, bathrooms, basements, additions, coach houses, and mobility renovations across the city. Named Best of TrustedPros in 2024 with a strong review history on HomeStars and TrustedPros.
View RenosGroupMore basement finishing
FeaturedBarrhaven +6
5.0(180)on GoogleChecked Aug 2026FencingAMA United Company Inc. is a fence contractor in Ottawa. Rated 5 from 179 Google reviews.
View AMA United Company Inc.
FeaturedBraden Foundation Construction is a waterproofing service in Ottawa offering concrete work and drainage. Rated 5 from 105 Google reviews.
View Braden Foundation Construction
FeaturedStittsville
5.0(109)on GoogleChecked Aug 2026Kitchen & Bath RenovationCapital Bathroom Renovation is a bathroom remodeler in Stittsville, Ottawa. Rated 5 from 109 Google reviews.
View Capital Bathroom Renovation
ConstructEvo Inc. is a construction in Ottawa offering basement finishing. Rated 5 from 27 Google reviews.
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ClaimedNepean +6
4.7(37)on GoogleChecked Aug 2026General ContractorsOttawa design-build contractor established in 2005 for kitchens, bathrooms, basements, whole-home renovations, additions, accessibility upgrades, and commercial spaces.
View Dream Touch Renovations
IK Home Improvement INC. is a construction in Ottawa offering bathroom renovation and kitchen renovation. Rated 5 from 31 Google reviews.
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FeaturedJD Swallow Heating & Cooling is an air duct cleaning service in Ottawa offering heating and cooling. Rated 4.9 from 1466 Google reviews.
View JD Swallow Heating & Cooling
Kanata +7
4.2(20)on GoogleChecked Jul 2026Basement FinishingOttawa basement design-build firm specializing exclusively in finished basements and basement renovations, with decades of local experience.
View Just Basements
FeaturedMagnolia Design & Build is a construction in Ottawa offering bathroom renovation and kitchen renovation. Rated 4.8 from 125 Google reviews.
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Ottawa Bath Renovation is a handyman/Handywoman/Handyperson in Ottawa offering bathroom renovation and heating and cooling. Rated 5 from 55 Google reviews.
View Ottawa Bath Renovation
Nepean +4
4.4(233)on GoogleChecked Aug 2026General ContractorsHigh-volume Ottawa design-build renovation company based in Nepean, offering kitchen, bathroom, and basement renovations, home additions, coach homes, and custom homes. One of the most-reviewed renovation firms in the city.
View Ottawa General Contractors (OGC)
Barrhaven +6
4.9(40)on GoogleChecked Aug 2026Basement FinishingOttawa Home Renovation by Greenlight Renovation is a general contractor in Ottawa offering general contracting. Rated 4.9 from 40 Google reviews.
View Ottawa Home Renovation by Greenlight Renovation
Ottawa Renovation Pro ltd is a general contractor in Ottawa offering general contracting. Rated 5 from 36 Google reviews.
View Ottawa Renovation Pro ltd
Barrhaven +5
4.9(140)on GoogleChecked Aug 2026Windows & DoorsWestend Windows and Doors is a door supplier in Ottawa offering window installation and windows. Rated 4.9 from 140 Google reviews.
View Westend Windows and Doors
Nepean +2
Basement WaterproofingOttawa-area waterproofing company covering interior and exterior basement waterproofing, weeping tile, sump pumps and backwater valves. Provides a 3-year labour warranty and free online quotes.
View iBasementsBuyer guide
What separates a great basement renovation company from a cheap quote, and the questions worth asking before you sign.
Finishing over a damp basement traps the problem behind new walls. A good contractor checks for water and addresses waterproofing or drainage before framing starts.
A finished basement, and especially a bedroom or secondary suite, needs City of Ottawa permits and code-compliant egress windows. Confirm the contractor handles this; it protects resale and safety.
Ottawa basements are cold. Proper insulation and a vapour barrier keep the space comfortable and prevent mould. Ask how they insulate the foundation walls.
Basement scope creeps easily. Look for a contractor who gives itemized, fixed pricing and a clear change-order process so the final bill holds no surprises.
Common questions
For homeowners
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