Egress Window Requirements in Ontario: Cost, Legal Basement Rules & Installation Guide
- Tricity windows and doors
- 3 days ago
- 4 min read
For many homeowners, the basement starts as storage space and slowly turns into something much more.
Maybe your kids are getting older and need their own room. Maybe you’re planning an in-law suite for family. Maybe you’re trying to create a legal basement apartment for rental income.
Then someone mentions one thing that catches homeowners off guard your basement bedroom may need an egress window.
A customer calls us thinking they simply need a new basement window, but after looking at the space, we often discover the real issue is that the current window opening is too small to meet modern egress requirements.
This is especially common in older Ontario homes where basement windows were built small and weren’t designed for bedrooms or rental spaces.
Before you spend money finishing your basement, here’s what you should know.
What is an egress window?
An egress window is a window designed to provide a safe emergency escape route.
If there’s ever a fire, smoke emergency, or blocked staircase, anyone sleeping in the basement needs another way to get out safely.
The window must open easily from the inside without tools, keys, or complicated steps.
This is why egress windows are often required when converting basements into bedrooms, rental apartments, or secondary suites.
Do you need an egress window for a basement bedroom in Ontario?
In many cases, yes.
Ontario building code generally requires basement bedrooms to have a safe emergency exit.
That usually means:
A minimum unobstructed opening of 0.35 square metres
No dimension smaller than 380 mm
The window must fully open from the inside
No tools or keys required
Proper clearance if there is a window well outside
Municipal rules can vary depending on where you live, so homeowners should always verify requirements before beginning renovations.
This becomes especially important when building legal basement apartments in Kitchener, Waterloo, Cambridge, and Guelph.
Why older basement windows often don’t meet code?
This is something we see regularly.
Many older homes were built with small basement sliders or hopper windows that simply don’t provide enough escape space.
Sometimes the window itself is fine, but the opening is too small.
Sometimes the window well outside doesn’t provide enough room.
Sometimes the window is difficult to fully open.
We’ve seen homeowners fully finish their basement only to find out later their bedroom doesn’t meet legal safety requirements.
That can become an expensive mistake.
Can you enlarge a basement window for egress?
Yes, and many homeowners do exactly that.
Instead of creating an entirely new opening, many projects involve enlarging the current basement window.
This may include cutting concrete foundation walls, expanding the opening, installing a larger window, adding drainage, or installing a proper window well.
These projects should be done carefully because structural work needs to be handled properly.
How much does an egress window cost in Ontario?
This depends on the type of project.
A straightforward basement window replacement is usually less expensive than a full egress conversion.
Costs often depend on:
Window size
Type of window
Foundation cutting
Window wells
Drainage requirements
Permit fees
Interior repairs after installation
The best way to get accurate pricing is through an in-home assessment because every basement is different.
What type of windows work best for egress?
Several window styles may work depending on your opening.
Popular options include:
Hopper windows
Casement windows
Tilt and turn windows
Larger basement sliders in certain situations
The right option depends on both safety requirements and the layout of your home.
Do you need permits for basement egress windows?
Often yes.
Especially if you are:
Creating a legal basement apartment
Adding a bedroom
Cutting foundation walls
Making structural changes
Permit requirements can vary depending on your municipality, so it’s always smart to confirm before starting work.
Why homeowners install egress windows?
Safety is the biggest reason.
But it’s not the only one.
Homeowners often install egress windows to create legal rental apartments, build in-law suites, add bedrooms for growing families, bring more natural light into dark basements, and increase property value.
Many homeowners are surprised by how much brighter and more comfortable a basement feels after upgrading old small windows.
Frequently asked questions about egress windows in Ontario
Do I need an egress window for a legal basement apartment in Ontario?
In many cases, yes. Bedrooms in basement apartments typically need proper emergency exits.
What size should an egress window be in Ontario?
Ontario generally requires at least 0.35 square metres of unobstructed opening and no dimension less than 380 mm.
Can I use my existing basement window?
Sometimes, but many older basement windows do not meet current requirements.
How long does egress window installation take?
Simple replacements may be faster while projects involving concrete cutting usually take one day.
Who installs egress windows near me?
At Tricity Windows and Doors, we help homeowners across Kitchener, Waterloo, Cambridge, and Guelph upgrade basement windows and create safer living spaces.
If you’re planning a basement renovation, rental unit, or extra bedroom, it’s always better to understand egress requirements before construction starts. It can save you thousands later and help make sure your new space is both safe and legal.
Comments