Almost every window company will tell you their windows are energy efficient, and almost all of them are telling the truth. Modern vinyl windows from reputable manufacturers perform within a narrow band of each other. What varies enormously is the installation - and a well-made window installed badly will underperform a mediocre window installed properly, every time.
The distinction to understand before you get quotes is between a retrofit installation, where the new window fits inside the existing frame, and a full-frame installation, where everything comes out down to the rough opening. Retrofit is cheaper and faster. Full-frame is the only way to find and fix rot, and the only way to properly air-seal and insulate the gap around the window.
What window & door installers do
- Replacement windows - vinyl, fibreglass, wood-clad
- Entry doors, storm doors and sidelights
- Patio sliders and French doors
- Bay, bow and casement configurations
- Capping, trim and exterior finishing
- Egress window installation for basement bedrooms
Does a window and door installer need a licence in Ontario?
No provincial licence is required. Installation quality is governed by manufacturer specification and the Ontario Building Code rather than by a trade certificate.
General liability insurance and WSIB clearance
Standard checks. Window installation involves ladder work and heavy glass.
Manufacturer-trained installer status
Matters more than usual here, because most window warranties are voided by installation that departs from the manufacturer specification.
Building permit for new or enlarged openings
Replacing a window in an existing opening generally does not need one. Cutting a new opening, or enlarging one for a basement egress window, generally does.
Verify with: Your municipal building department confirms what your specific job requires.
ENERGY STAR certification for the product
Relevant if you intend to claim any efficiency rebate, which typically requires certified products and documentation.
What it costs in Ontario
Per-window pricing drops as quantity rises, so a whole-house quote is rarely the single-window price multiplied out. Be careful comparing quotes where one is retrofit and the other is full-frame. They are different jobs, and the cheaper one is not necessarily the worse deal, but you should know which you are buying.
| Job | Typical range |
|---|---|
| Standard vinyl window, installedRetrofit at the low end, full-frame with capping at the high end. | $700 – $1,600 |
| Whole house, roughly 15 windowsVolume pricing usually applies. Confirm whether it is retrofit or full-frame. | $12,000 – $25,000 |
| Bay or bow windowNeeds structural support and roof detailing above. | $2,500 – $5,500 |
| Entry door, installedFibreglass with sidelights sits at the top of the range. | $1,800 – $5,000 |
| Patio slider or French doorsSill preparation matters more than the door on these. | $2,000 – $4,500 |
| Basement egress windowIncludes excavation, cutting the foundation, and a window well. | $3,500 – $8,000 |
These are planning estimates for Ontario, not quotes, and they move with material prices and demand. Use them to sanity-check a quote, not to argue one down.
Questions to ask before you hire
- 1Is this a retrofit or a full-frame installation? What would the other one cost?
- 2How is the gap between the window and the rough opening insulated and air-sealed?
- 3Is exterior capping included, and in what colour and material?
- 4Is the warranty on the glass seal, the frame, and the labour - and are they different lengths?
- 5Is the warranty transferable if I sell the house?
- 6Are your installers employees or subcontractors, and are they manufacturer-trained?
- 7What is the lead time, and what happens to my deposit if it slips?
Warning signs
- A very large discount available only if you sign during the in-home visit. This is the most common high-pressure sales pattern in this trade.
- A quote that names no manufacturer or product line.
- "Lifetime warranty" with no written definition of whose lifetime, what is covered, and what voids it.
- A deposit above roughly a third of the job value before materials are ordered.
- No mention of how the opening will be sealed - the part that actually determines efficiency.
How to read reviews for this trade
This trade has more aggressive in-home sales than any other on this site, so weight reviews that describe the sales process as much as the installation. Reviews mentioning a salesperson who left without a signature and did not badger afterwards are a genuinely useful signal. Watch for seal failures mentioned in reviews two or three years old. That is the failure mode that matters.