Three window quotes for the same house can come back at $9,000, $14,000, and $21,000, and the cheapest is not always the worst deal or the most expensive the best. The difference is almost always in what’s written, or not written, on the page. Here’s how to read a window quote line by line, what a complete one includes, and the phrases that tell you something is being hidden.
What a Complete Quote Contains
A window quote is a specification, not a price. If you can’t hand it to a different installer and have them build the same job from it, it’s incomplete. At minimum, for every opening:
- Location (e.g. “front bedroom, west”) and rough size.
- Manufacturer and product series.
- Style (casement, slider, hung, fixed, awning), and configuration for multi-unit windows.
- Frame material and interior and exterior colour.
- Glass package: panes, Low-E type, gas fill, spacer, any tempered or laminated glass.
- Energy ratings: ER and U-factor, and ENERGY STAR® certification.
- Hardware and screens.
- Installation method (retrofit or full-frame) and finishing inside and out.
- Price per opening, subtotal, HST, total.
The Product Lines
Two windows from the same manufacturer can differ by hundreds of dollars and a full point of ER depending on series. “Vinyl casement” is not a specification. Look for the series name, then check it on Natural Resources Canada’s certified product list. Glass is the same: “energy-efficient glass” means nothing; “double-pane, Low-E 272, argon, Super Spacer” means something. If a quote doesn’t say triple-pane, it’s double. If it doesn’t say the spacer, ask; aluminum spacers are the cheapest and worst.
The Installation Lines
This is where quotes diverge most. Look for:
- Method. Retrofit (insert) or full-frame (brick-to-brick). They’re different jobs at different prices; see our guide. A quote that doesn’t say is almost certainly retrofit.
- Exterior finishing. New brickmould? Aluminum capping over old wood? Caulking type?
- Interior finishing. Jamb extensions, casing, and who paints them.
- Insulation. Low-expansion foam around every frame should be stated.
- Disposal of old windows and debris.
- Who installs. The company’s own crew or a subcontractor? Both can be excellent, but you should know who’s standing on your ladder.
The Money Lines
- HST. 13 percent. If it’s not on the quote, add it before comparing.
- Deposit. 25 to 50 percent at signing is normal for made-to-order product; 100 percent up front is not.
- Payment schedule. Balance on completion, not on delivery.
- Price validity. 30 to 60 days is standard. “Today only” is a sales tactic.
- Extras. A unit price for rot repair or unexpected framing, so surprises are priced in advance.
- Financing terms, if offered: rate after any promotional period, and total cost of borrowing. See our financing guide.
The Warranty Lines
Two warranties, and the quote should name both. The manufacturer’s covers the frame and the sealed glass unit, with separate terms for each, and it should say whether it’s prorated and transferable. The installer’s labour warranty covers the installation itself, in writing, for a stated number of years. Our warranty guide explains what each actually pays for.
Red Flags
- A single lump sum with no per-window pricing. You can’t compare it or remove a window from it.
- A big discount that expires tonight. The real price is the discounted one; the “regular” price is fiction.
- “Lifetime warranty” with no document attached.
- No ratings listed. If they won’t write down the ER, ask why.
- No installation method stated.
- Pressure to sign at the kitchen table. A commissioned salesperson’s pay depends on it; your decision shouldn’t.
- A price far below the others. Something is missing or the install is being cut short. Flashing and insulation are invisible when the job is done and are the first things to go.
- No HST shown and no mention of it.
How to Compare Three Quotes Fairly
- Put them side by side in a spreadsheet, one row per opening.
- Normalize the glass: if one is triple-pane and two are double, ask the double-pane companies to price triple, or the triple-pane company to price double.
- Normalize the method: retrofit versus full-frame.
- Add HST and any finishing not included.
- Now compare price, ER, and warranty. The best quote is usually the one with the best ratings and the clearest scope at a price within 10 to 15 percent of the lowest.
Questions to Ask Before Signing
- What is the ER and U-factor of each window on this quote?
- Is this retrofit or full-frame, and why did you choose that for my house?
- What happens if you find rot when the old window comes out?
- Who is installing, and are they insured and WSIB-covered?
- How long is your labour warranty, and can I see it in writing?
- What is the lead time right now, and when would I be installed?
- Is the price good for 30 days?
For what the numbers should look like, see our 2026 cost guide.
Want a Quote That Answers All of This?
Ours lists every opening, every rating, the method, the finishing, the warranties, and the HST. No commission and no expiry pressure.
A family-owned business that supplies and installs high-quality windows and doors throughout Mississauga, Oakville, London, and surrounding areas in Ontario. Over 20 years of experience and a reputation built entirely on customer referrals.