Windows & doors
Window Replacement in Cornwall, Ontario
ENERGY STAR windows and doors, installed square, air-sealed and properly flashed — because a good window fitted badly performs like a bad window.
Most of the performance you pay for in a new window is won or lost in the two hours it takes to install it. A high-spec triple-glazed unit stuffed into a rough opening with a bead of foam and no flashing will still be draughty, and it will still let water into the wall. The glass is the easy part.
We install square and plumb, shim at the load points rather than wherever is convenient, use low-expansion foam so the frame is not bowed by its own insulation, seal the interior air barrier, and flash the exterior so water that reaches the opening is directed back out. Then we finish the trim properly, inside and out, so the job is actually done.
Scope of work
What a window replacement includes
Measure and specification
Every opening measured individually — older Cornwall homes are rarely square, and ordering from one measurement repeated across a house is how you end up with gaps stuffed with foam.
Retrofit or full-frame
We will tell you honestly which one your house needs. Full-frame costs more and is the right answer when the existing frame is rotten or the wall needs to be sealed properly; retrofit is fine when the frame is sound.
Air sealing
Low-expansion foam plus a sealed interior air barrier. This is where the comfort difference actually comes from, and it is the step most often skipped.
Exterior flashing and capping
Sill pan and head flashing so water is shed outward, and aluminum capping on exterior trim for a finish that does not need painting.
Interior trim and finish
Casing, sills and caulking finished to a paint-ready standard. We leave the room usable, not full of unfinished openings.
Basement egress windows
Enlarging a basement opening to meet the Ontario Building Code egress requirement for a bedroom, including the cutting, lintel and window well. Needed for any legal basement bedroom.
Options
Windows and doors we install
Matched to the opening, the room and the exposure.
Casement and awning
Crank-operated, and they seal against the frame under compression, which makes them the best performers against wind-driven rain and draughts. The default choice for exposed elevations.
- Best air-tightness
- Full opening for ventilation
- Ideal for exposed walls
Double and single hung
The traditional look for older Cornwall homes and heritage-style elevations. Slide vertically, so they take no exterior space over a walkway or patio.
- Classic appearance
- No exterior swing
- Tilt-in cleaning options
Sliders and picture windows
Sliders for wide openings, fixed picture units where the priority is light and view rather than ventilation. Fixed units are the most air-tight of all, because there is nothing to seal.
- Maximum glass area
- Cost-effective on wide openings
- Fixed units seal best
Entry and patio doors
Insulated steel and fibreglass entry doors, sliding and swing patio doors. Doors are where air leakage is most noticeable, so hardware quality and threshold detail matter more than the slab.
- Insulated fibreglass and steel
- Multi-point locking available
- Sliding and swing patio
Ontario’s Home Renovation Savings Program — $100 per opening
Ontario’s Home Renovation Savings Program offers $100 per eligible ENERGY STAR-certified window or door rough opening, with the current funding window running to 30 November 2026. Across a whole-house replacement that adds up.
The rebate can only be claimed when the work is done by a contractor registered with the program as a Participating Contractor, and larger bundled rebates (combining windows with insulation and air sealing) require a pre- and post-retrofit energy assessment. Ask us where your project stands before you order, and confirm the current program terms at saveonenergy.ca — terms and deadlines change.
Service areas
Windows across Cornwall & SD&G
Based in Cornwall and working across Stormont, Dundas and Glengarry. If your town is not listed, call us anyway — we travel.
FAQ
Windows: common questions
Is there a rebate for replacing windows in Ontario?
Yes. Ontario's Home Renovation Savings Program pays $100 per eligible ENERGY STAR-certified window or door rough opening, with the current funding window running to 30 November 2026. It has to be claimed through a contractor registered with the program, and bundling windows with insulation and air sealing can unlock larger totals but requires an energy assessment before and after. Confirm the current terms on the Save on Energy website before budgeting around it.
How much does window replacement cost in Cornwall?
Published figures for standard vinyl replacement windows in this area have ranged from roughly $300 to $800 per window installed, but that spread is wide because it hides the variables that matter: window type, glazing package, whether the install is retrofit or full-frame, and whether the opening needs structural work. Casements cost more than sliders. Full-frame costs more than retrofit. We quote per opening, in writing.
Should I get double or triple glazing?
Triple glazing is meaningfully better in an Eastern Ontario winter, and the difference you actually notice is not the heating bill — it is that the glass is not cold to sit beside, and the condensation stops. It costs more and it is heavier. On a north-facing wall or a room you use every day, we would spend the money. On a rarely-used space, double glazing is fine.
What is the difference between retrofit and full-frame installation?
Retrofit leaves the existing frame in place and fits the new window into it. It is faster, cheaper and less disruptive, and it slightly reduces your glass area. Full-frame removes everything back to the rough opening, which is the only way to inspect for rot, install a proper sill pan and air-seal the opening correctly. If the existing frames are sound, retrofit is fine. If there is any rot or draught at the perimeter, full-frame is the honest answer.
Do I need a permit to add or enlarge a window?
Replacing a window in an existing opening generally does not need one. Cutting a new opening or enlarging an existing one does, because it affects the structure — a header or lintel has to carry the load above. Basement egress windows for a bedroom almost always fall into this category, and they have minimum size and opening requirements under the Ontario Building Code. We handle the permit application.
Free quote
Get a free quote for your window project
Tell us what you are planning. We reply to every inquiry, usually within one business day.
Services
Other things we do
Deck building
Custom pressure-treated, cedar and composite decks engineered for Eastern Ontario frost.
Read more 02Fence installation
Privacy, picket, PVC, aluminum and chain link — set deep, set straight, set square.
Read more 03Siding installation
Vinyl, engineered wood and board-and-batten, with soffit, fascia and eavestrough.
Read more 05Bathroom renovations
Full gut-and-rebuild bathrooms, tub-to-shower conversions and accessible walk-ins.
Read more 06Kitchen renovations
Layout changes, custom cabinetry, islands and finish carpentry done by one crew.
Read morePrefer to talk it through first?
Call us and describe what you are dealing with. We will tell you honestly whether it is a job worth doing now.