Replacing a thermos is one of the most cost-effective repairs out there: we replace the sealed unit within the existing frame, at a fraction of the price of a new window. But how much does it really cost in 2026? Here are the numbers, with no hidden fees.
The average price per unit
Our prices start at around $150 per unit. For a small double-glazed window, expect between $150 and $250. An average window is closer to $250–$400, and a large window or patio door between $400 and $700.
These ranges are indicative. The firm price is confirmed at the free diagnosis, once the dimensions and glass type are validated.
What drives the price
- Dimensions: the larger the pane, the higher the cost in glass and argon gas.
- Glass type: double, triple or Low-E, each option has its square-foot rate.
- Accessibility: the floor, condo type and access to the frame affect installation time.
- Quantity: several units at once qualify for a volume discount.
- Hardware: some frames require specific parts.
Double, triple or Low-E argon?
Double glazing is the reliable standard for most windows. Triple glazing significantly improves insulation but costs about 20–40% more and slightly weighs down the unit — it's mainly justified on north-facing or highly exposed facades.
Low-E (low-emissivity) glass with argon gas is often the best value: an invisible coating reflects heat inward in winter and limits overheating in summer.
Thermos vs full window
| Criteria | Thermos | Full window |
|---|---|---|
| Estimated cost | $150 – $450 | $700 – $1,200+ (installed) |
| Timeline | 24–72 h fabrication | Several weeks |
| Work | Frame kept, light install | Full removal and finishing |
| Lifespan | Comparable to a new window | New, but more expensive |
Estimate yours
Estimated range
$150 – $177
Indicative estimate, price confirmed at the free diagnosis.
How to get a fair quote
Beware of overly vague ranges or salespeople who always push toward a new window. A fair quote is based on precise dimensions, a clearly identified glass type and a firm written price.
Our diagnosis is free and without obligation: we measure, confirm the condition of the frame, and give you a written quote. See our pricing page for the full breakdown. Thermos replacement pricing.
What about home insurance?
A descaled thermos is rarely covered by insurance, as it falls under normal wear and tear. However, a pane broken by an impact (hail, vandalism, falling object) may be. We always provide the necessary documents and invoice, and we can help you prepare your claim.
