Basement renovation in Ottawa
Tell us what the basement is now and what it should become. One independent Ottawa renovation company gets the request and calls to arrange a visit and a quote.
In short
- 01Whole basement renovation in Ottawa: $35,000–$95,000 (HomeStars Ottawa 2026 guide).
- 02Open rec room of 600–800 sq ft: $25,000–$45,000; basement bathroom: $8,000–$30,000.
- 03Finishing a basement needs a City building permit; the first permit check takes about 5 business days.
- 04The price moves with a bathroom, egress windows ($3,500–$6,000 each) and waterproofing ($5,000–$15,000).
Typical ranges
Source Sources: HomeStars, Basement Renovation Cost for Ottawa: 2026 Guide (updated 21/08/2026), https://www.homestars.com/home-constructions-renovations/price-guides/basement-renovation-cost-ottawa ; City of Ottawa, Comprehensive Building Code Fee Schedule (January 1, 2026), https://ottawa.ca/en/planning-development-and-construction/building-and-renovating/forms-applications-and-fees/comprehensive-building-code-fee-schedule ; City of Ottawa, Finishing a basement, https://ottawa.ca/en/planning-development-and-construction/building-and-renovating/do-i-need-building-permit/finishing-basement
What to ask before you book
- Q1Are the permit drawings and the permit fee in your price, and who books the City inspections?
- Q2How do you check the walls and floor for moisture before framing, and what happens if you find water?
- Q3If I want a bedroom down there, how will the window meet egress rules?
- Q4Will you wait for each City inspection before you close the walls?
- Q5How are payments tied to stages of the work?
Before the visit
- Photos of every wall, the floor, the furnace, water heater, sump pit and electrical panel.
- Any history of water: when, where, and what was done about it.
- A floor sketch with rough measurements and the ceiling height under the ducts.
- What the space is for: family room, bedroom, office, bathroom, rental suite.
Begin with what is down there now
The contractor prices from what the basement is today. Put these in the request:
- Current state. Unfinished, partly finished, or finished and getting redone.
- Size and height. Rough square footage and clear height under the ducts.
- Water. Any leak, damp corner or past flood. Put it first, even if it was years ago.
- Mechanical. Where the furnace, water heater, sump pit and panel sit.
- The goal. Family room, bedroom, office, bathroom or a rental suite.
Example: “Unfinished basement, about 700 sq ft, 2005 house in Barrhaven. Rec room and a 3-piece bathroom. Dry so far, sump pit in the corner.”
Ranges by room
HomeStars’ 2026 Ottawa guide puts a whole basement renovation at $35,000–$95,000. An open rec room of 600–800 sq ft runs $25,000–$45,000. A bathroom adds $8,000–$30,000, a bedroom $15,000–$30,000. Each egress window costs $3,500–$6,000, and waterproofing with insulation upgrades adds $5,000–$15,000. A legal secondary suite sits at $80,000–$120,000.
The permit path
Finishing a basement is a permit project in Ottawa. The application needs plans drawn to scale, and the fee is $12.75 per $1,000 of construction value, minimum $117. After approval, the City inspects in stages, from plumbing rough-in through framing and insulation to the final. Work closed up before its inspection may have to be opened again, so ask the contractor how they schedule around the inspector.
A bedroom needs a window that meets egress rules under the Ontario Building Code. Ask the contractor to confirm the size on the drawings.
On the call
Have the photos and the water history ready. Ask for a written quote that lists the permit, drawings and each room separately.
Who does what
A basement brings in several trades: framer, plumber, electrician, drywaller, flooring installer. Ontario’s renovation guide says the contract names any sub-trades and who pays them, and states who gets the permits. Electrical work goes through the Electrical Safety Authority, separate from the City permit. Ask whether the company has WSIB coverage for its workers; a WSIB clearance certificate is easy to check online.
Who gets your request
613 Pros sends your basement request to one independent local renovation company. They call, ask what they need and arrange to see the space.
Questions
01Do I need a permit to finish a basement in Ottawa?
Yes. The City lists finishing a basement as a permit project. You need a permit application, the fee and a full set of plans drawn to scale. Applications go through My ServiceOttawa, and the City’s first check takes about 5 business days.
02What does the City inspect?
Depending on the job: excavation, plumbing underground and rough-in tests, framing, insulation and vapour barrier, plumbing final and a final inspection. Inspections are booked 48 hours ahead, and work covered before an inspection may have to be opened up again.
03How much is the permit?
$12.75 per $1,000 of construction value with a $117 minimum. On $40,000 of work that comes to about $510.
04What does a legal basement suite cost?
HomeStars’ Ottawa 2026 guide puts a legal secondary suite at $80,000–$120,000. Write “legal suite” in the request so the contractor plans the drawings for it from the first call.
05Is there help for flood protection?
The City of Ottawa runs a Residential Protective Plumbing Program with rebates for backwater valves and sump pumps. It needs a building permit and City inspections. Check the current amounts on ottawa.ca before you plan around them.
06Who does the work?
An independent local renovation company. 613 Pros passes your request to one company, and you agree the scope, price and contract with them.