If you’re researching basement egress windows in Ottawa, this guide covers code compliant installations, permits, and smart placement.
Your Life Passage to Safety.
Your Light Connection to Sunshine.
Adding a basement egress window is more than just a building code requirement - it’s a growing trend across Greater Ottawa and Ontario that brings comfort, safety, and peace of mind to homeowners.
Whether you're creating a rental suite, improving safety for loved ones, or upgrading your home office, egress windows offer a unique opportunity to transform your basement into a brighter, safer, and more livable space.
Why Homeowners Are Investing in Basement Egress Windows in Ottawa
At Mr. Foundation, we’ve worked with a wide range of clients who choose to install basement egress windows for different reasons:
- 🛏️ Rental Income: Many homeowners are converting basement bedrooms into rental spaces to help offset rising living costs.
- 🛡️ Safety Concerns: Families want peace of mind knowing there’s a safe exit in case of emergency.
- 💼 Work-from-Home Comfort: A dark basement office can affect productivity and well-being - natural light makes a big difference.
Egress windows are more than just a legal checkbox. They’re a way to bring light, safety, and comfort into your home. These are the most common reasons homeowners add basement egress windows in Ottawa.
Why Are Ontario Basements So Deep?
Ever wondered why Ontario homes have such deep basements? The answer lies beneath your feet - literally.
Ontario’s climate demands deep foundations to protect against frost. In Ottawa, the soil depth requirement for heated spaces is 5 feet above the footing. This thermal mass preserves geothermal heat and prevents frost from forming below the foundation, which could cause structural damage.
Builders have taken this necessity and turned it into an opportunity: by extending the depth beyond 5 feet, they’ve created livable basement spaces. Today, 8-foot concrete forms are the norm, giving us the underground comfort we enjoy.
Ontario Building Code rules for basement egress windows in Ottawa
When it comes to basement bedrooms, it’s important to distinguish between a simple bedroom setup and a separate dwelling unit. If your basement includes a kitchen with an oven, it’s considered a separate suite and subject to additional regulations not covered here.
In Ontario we build and renovate in accordance to the Ontario Building Code, not the National Building Code (NBC). The biggest difference between the two code compendiums for egress windows is the window location requirements. The NBC wants an egress window in every bedroom that does not have a door. The OBC only requires a minimum of one egress window per floor level that has one or more bedroom(s). The OBC does not require the egress window to be in the bedroom. It must be on the same floor level. This is a good time to add that in Ontario a bedroom must have a window.
For basement egress windows in Ottawa, the OBC sets the size, clearance, and sill height rules.
What makes a basement egress window OBC compliant?
| Requirement | Requirement | Clause (Div B) |
|---|---|---|
| Window minimum opening size | Both the height and width of the openable area must be at least 380 mm each Minimum area requirements of 0.35 m² |
9.9.10.1.(1) |
| Minimum Clearance | For escape windows that open into a window well, a minimum clearance of 550mm is required from the open window to the front of the window well to allow for emergency escape. | 9.9.10.1.(3) |
| Number of Egress Windows | every floor level which contains a bedroom to have at least one window or door to the exterior that | 9.9.10.1.(2) |
| Sill Height (Basement Bedroom Windows) | It is RECOMMENDED that the sills of windows intended for use as emergency exits from basement bedroom areas be not higher than 1.5 m above the floor Sometimes it is difficult to avoid having the sill higher than this - e.g., skylights, windows in basement bedrooms. In these cases, it is recommended that access to the window be improved by some means such as built-in furniture installed below the window. |
9.9.10.1, 9.9.10.1.(2) |
References align with the 2024 OBC - Div B and the City of Ottawa advisory. See O. Reg. 163/24 and City of Ottawa - Egress windows advisory.
Also, every bedroom in Ontario must have a window that meets minimum daylight requirements - but it doesn’t have to be egress-compliant.
Do you need basement egress windows in Ottawa?
✅ Yes - if you have a bedroom in the basement. It’s a legal requirement and a smart safety upgrade.
Where should you put basement egress windows in Ottawa?
Most homeowners assume the egress window must go in the basement bedroom. While that’s possible, consider this: if the existing bedroom window already meets daylight requirements, why not install the egress window elsewhere?
Adding it in another part of the basement spreads natural light more evenly and enhances the overall livability of the space. It’s another example of turning a requirement into a comfort. Placement of basement egress windows in Ottawa depends on light, layout, and exterior constraints.
Exterior limits for egress window installation in Ottawa
Gas Lines
Gas lines pose a potential problem for installing the deeper window wells required for basement egress windows. If the desired basement egress window location is between the gas metre and direction from which it is serviced (typically from the street). Often the gas line will require an extension to travel around the new window well.
Overhangs
1st floor bump-outs like cantilevered bay windows that would overhang above the new basement egress window well. For an Ottawa client we were able to overcome this obstacle by providing a window well that project 550mm beyond the extent of the overhang.
Decks
A basement egress window can not be located under a shallow deck without a cutout in the deck that surrounds the egress window well to provide an unobstructed exit.
Property Line Limiting Distance
A basement egress window well cannot encroach onto a neighbour’s property. So a there must be a minimum of 550mm to the property line (for window styles that do not open outwards).
HVAC Venting
Venting for combustible mechanical units must maintain a minimum distance form windows. For units under 100,000 BTU/hr 300mm is the minimum and for all units exceeding 100,000 BTU/hr the minimum distance is 900mm.
Masonry Veneer Cladding
A basement egress window can be installed under masonry units as long any new opening cut into the foundation is topped with a steel masonry lintel. This steel is crucial for bearing the weight of the masonry over the new opening. The proper method of installation of the steel is to remove the masonry immediately above the new opening and reinstate on the new steel lintel. This method completely hides the steel and provides the best aesthetics.
Frost Protection of Footings Below A Lowered Grade Level (inside the window well)
As mentioned earlier frost must always be accounted for when modifying the grade level above foundation footings. Because the backfill within the window well will be lower the engineer or BCIN signee must account for frost protection if the new backfill levels or below the 5 feet requirement for heated spaces. Frost protection can be achieved with the introduction of rigid insulation over the footings and up the wall to grade. The thickness and scope of the rigid insulation will change from job to job depending on site conditions.
Total Aggregated Length of Openings on a Wall
A foundation wall can only be opened so much without compromising its lateral stability. On site calculations are need to determine if the wall will require lateral stabilization. Thy your contractor when deciding where to place the new basement egress window. It should also be verified by the engineer and/or design authority for your project.
Do I Need a Permit?
I once had a young gentleman approach me at our display booth at the Ottawa Home Show with a question: "Is a building permit required if you're only cutting the foundation below an existing basement window without making it wider?" My answer: "YES." His response, as he walked away: "BS."
I often think of that moment because I’m frequently asked about building permit requirements for basement egress windows. So let me reaffirm the answer: Yes, a building permit is required for the installation of a basement egress window - whether you're enlarging an existing opening or creating a new one.
Here’s a quick breakdown:
- 🏠 Modifying the structure of a home: Permit required
- 🪟 Installing a window in a new opening (on any floor): Permit required
- 📏 Enlarging a window opening (on any floor): Permit required
Your home is an asset, and permitted modifications protect that investment. Proper documentation makes refinancing, securing insurance, and selling your home much easier when the time comes.
Ottawa requires permits for basement egress windows in Ottawa whether you cut a new opening or enlarge one.
City of Ottawa - Finishing a basement
Do I Need an Engineer?
Hiring an engineer is never a bad idea. They’ll visit the site, assess the structural elements affected by the new or enlarged foundation opening, and provide tailored recommendations. Their expertise ensures the work meets safety and code standards.
Structural drawings must be submitted with your building permit application. If the drawings aren’t signed by a professional with a Building Code Identification Number (BCIN) or a P.Eng stamp, they must include a Schedule 1 form identifying who is taking responsibility.
If you skip the BCIN or P.Eng stamp, you're taking a risk with your home's structural integrity.
To clarify:
You don’t necessarily need a structural engineer - drawings signed by a BCIN holder are acceptable.
However, relying on a contractor to submit a Schedule 1 without professional credentials should be approached with extreme caution.
What Happens to the Excavated Soil?
At Mr. Foundation, we remove all excavated (native) soil from the property and dispose of it off-site. We backfill our basement egress window installations with clear stone aggregate.
Here’s why that matters:
Contractor Advantages:
- Clean and obstacle-free worksite
- Safe and efficient installation
Client Benefits:
- No mess left behind
- No soil settlement over the next 1-5 years
- No frost heaving around the new window well
- Improved drainage below the egress window
Not All Scopes of Work Are Created Equal
This applies to every home improvement project. At Mr. Foundation, we pride ourselves on setting the standard for best practices in foundation repair and waterproofing across Ottawa and the surrounding region.
A “fantastic” price often reflects a minimal scope of work and a bare-bones final product. On the flip side, an exorbitant quote may come from a contractor who’s too busy and only takes on projects with high financial returns.
The truth lies in the details of the quote. Every step of the process and every material used should be clearly outlined. Transparency is key to making informed decisions and ensuring quality results.
See related services: basement waterproofing, structural repair, foundation replacement, foundation crack repair, window well repair, service area, and FAQ.
Basement egress windows in Ottawa - final thoughts
Basement egress windows are a perfect example of how building code requirements can evolve into meaningful home improvements. They offer safety, light, and a chance to reimagine your basement as a vibrant part of your home.
If you're considering an egress window, think beyond compliance - think comfort, design, and peace of mind.
At Mr. Foundation, we don’t just meet standards - we set them. Our commitment to thoughtful excavation and quality materials ensures your basement upgrade is built to last. Ready to take the next step? We’re here to help.
Ready to plan basement egress windows in Ottawa with a code compliant installation?
Contact Mr. Foundation for Basement Egress Windows in Ottawa.