What is a foggy thermos and why does it happen?

A foggy thermos is a double- or triple-glazed sealed unit whose perimeter seal has failed. Over time, the seal degrades due to temperature changes, UV exposure and natural aging of materials. Once the seal is compromised, moisture enters between the panes and creates permanent condensation that cannot be cleaned from the outside. This reduces visibility and the energy performance of the window. Replacing the sealed unit is the most cost-effective and reliable solution.

Do I need to replace the whole window or only the thermos?

In most cases, you only need to replace the thermos (the insulated glass unit), not the entire frame or sash. This option is significantly more affordable and just as effective. Full replacement is usually only recommended if the frame is rotten, damaged or warped, if the opening mechanism is beyond repair, or if you want to change the style of the window.

How long is the warranty and what does it cover?

Manufacturer warranty: up to 10 years on insulated glass unit defects (seal, spacer, insulating gas). Labour warranty: 1 year on installation. If fogging returns during the manufacturer warranty period, the unit is replaced at no cost. Warranties remain valid with normal use.

How much does a thermos replacement cost?

Pricing depends on several factors: thermos size, glazing type (double vs triple, Low-E or not), shape (standard vs custom), frame material (wood, PVC, aluminum) and quantity. For an exact price, contact us for a free quote. We take the measurements and provide a detailed estimate with no obligation.

What is the typical installation timeline?

The complete process is typically 2 to 3 weeks: Day 1–2: visit and measurements, Day 3–7: approval and order, custom manufacturing, Day 10–21: reception and installation (usually completed in one day). Timelines can vary by season and project complexity.

Is caulking really necessary?

Yes. Caulking is essential and should be redone every 5 to 10 years. It can reduce heating/cooling costs by up to 20%, prevents water infiltration that can lead to mold and rot, eliminates drafts and protects your windows from damage. Signs you need recaulk: cracked, detached or hardened sealant, discoloration, drafts or moisture marks.

Do you offer split payments or financing?

We accept several payment methods: cash (cash/cheque), credit cards (Visa, Mastercard), Interac e-transfer, and split payment (50% upon order, 50% upon installation). For larger projects, contact us to discuss options that fit your needs. No payment is required before you approve the quote.

Experts in thermos and window installation

Fast, professional service across the North Shore and the Laurentians. Up to 10-year manufacturer warranty.

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Up to 10-year warranty

Up to 10-year manufacturer warranty on thermos and 1-year labour warranty

Fast service

Quick response and professional installation within agreed timelines

Free quote

Free assessment and quote with no obligation

Why choose Thermos A.M?

Over 6 years of expertise focused on your comfort

Our quality commitment

Since day one, Thermos A.M has specialized in thermos installation and foggy sealed-unit replacement, becoming a trusted reference across the North Shore and the Laurentians. Our proven expertise allows us to work quickly and efficiently on all window types: wood, PVC, and aluminum.

We work exclusively with certified manufacturers and offer premium products with up to a 10-year manufacturer warranty. Every job is performed by qualified technicians who follow the highest industry standards.

Our customer-first approach, fast response times, and attention to detail make us the preferred choice for hundreds of satisfied homeowners in the region.

Our competitive advantages

✓ Proven expertise Over 6 years of experience in window and thermos installation
✓ Competitive pricing Free quotes and transparent pricing — no hidden fees
✓ Fast service Response in 48–72 hours and careful installation on schedule
✓ Extended warranty Up to 10-year manufacturer warranty + 1-year labour warranty for peace of mind
✓ Turnkey service From measurements to installation — we handle everything end to end

Outer glass
Low-E coating

Argon gas
Thermal insulation

Inner glass
Triple glazing

The science behind our installations

Advanced technology for long-lasting results

🔬

High-performance triple glazing

Our thermos use triple glazing with argon gas for optimal thermal insulation and energy savings of up to 40%.

💎

High-tech sealing system

We use professional-grade seals designed for long-term airtight performance — even in Québec’s harsh climate.

🛡️

UV and thermal protection

Low-E coatings block up to 99% of harmful UV rays while keeping warmth in winter and cool air in summer — protecting your home and reducing bills.

10 yrs Manufacturer warranty

40% Energy savings

99% UV protection

Our 5-step process

A turnkey service for total peace of mind

Contact and assessment

Call us or use the form. We take the time to understand your needs and answer your questions. A free quote is prepared quickly, usually within 24 hours.

On-site visit and measurements

A qualified technician visits your home to inspect your windows and take precise measurements. We evaluate your frames and recommend the best options for your situation.

Custom manufacturing

Your new thermos are custom-made to exact specs by our certified manufacturing partners, using premium materials and warranted sealing systems.

Professional installation

Our experienced installers replace your thermos with care and precision. Work is done cleanly without damaging your frames or interior. We tidy up after installation.

✓

Warranty and follow-up

You receive your warranty documentation (up to 10 years manufacturer + 1 year labour). We remain available for any questions. Your satisfaction is our priority.

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Our specialized services

Complete solutions for all your window and door needs

Foggy thermos

Specialists in foggy thermos replacement. Eliminate condensation between panes with high-performance sealed units. Double and triple glazing available. Fast installation without replacing your existing frames. Clear glass backed by warranty.

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Doors & windows

Complete door and window installation. Measurements, adjustments, installation and hardware replacement (locks, hinges, handles). We install patio doors, French doors, and windows (sliders, awnings, casements). Clean, professional work.

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Caulking

Professional exterior caulking. Improves air and water sealing and can lower heating/cooling costs. We use durable products made to withstand harsh weather. Protect your home from leaks and drafts.

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Screens

Custom screen installation and fabrication. Replace torn mesh, damaged frames, or faulty latches. Door and window screens available. Durable materials and long-lasting installation for effective summer protection.

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Custom glass

Custom insulated glass units for all frame types: wood, PVC, aluminum, fiberglass. Single, double or triple glazing. Low-E, tinted or frosted options available. Exact sizing and precise installation guaranteed.

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Before / After

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What our customers say

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Service areas

Professional service across the North Shore and the Laurentians

North Shore

✓ Saint-Colomban
✓ Blainville
✓ Mirabel
✓ Saint-Eustache
✓ Boisbriand
✓ Rosemère
✓ Lorraine
✓ Sainte-Thérèse
✓ Deux-Montagnes
✓ Saint-Joseph-du-Lac

Laurentians

✓ Saint-Jérôme
✓ Sainte-Adèle
✓ Sainte-Agathe
✓ Val-Morin
✓ Prévost
✓ Saint-Sauveur
✓ Morin-Heights
✓ Piedmont
✓ Val-David
✓ Brownsburg

Don’t see your city listed?

We also serve many other municipalities within 50 km of Saint-Colomban. Contact us to confirm service availability in your area.

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Frequently asked questions

Everything you need to know

A foggy thermos is a double- or triple-glazed sealed unit whose perimeter seal has failed. Over time, the seal degrades due to temperature changes, UV exposure and natural aging of materials.

When the seal fails, moisture gets trapped between the panes and creates permanent fog that cannot be cleaned from the outside. This reduces visibility and lowers energy efficiency.

Replacing the thermos (not the full window) is typically the most cost-effective solution to restore clarity and insulation.

Most of the time, you only need to replace the thermos (the insulated glass unit), not the frame or the entire sash. It’s a much more affordable option with excellent results.

Full replacement is typically recommended only if:

The frame is rotten, damaged or warped
The opening mechanism is beyond repair
You want to change the window style or upgrade overall performance

During our visit, we inspect your frames and recommend the best solution based on your needs and budget.

Manufacturer warranty: up to 10 years
Covers insulated glass unit defects (seal, spacer, insulating gas). If fogging returns during that period, the unit is replaced at no cost.

Labour warranty: 1 year
Covers installation workmanship (adjustments, sealing, etc.). If an issue related to our work occurs, we fix it at no charge.

Note: Warranties apply under normal use. Damage from impact, accidents or modifications is not covered.

Cost depends on:

Size: larger units cost more
Glazing: double vs triple, Low-E or not
Shape: standard vs custom shapes
Frame material: wood, PVC, aluminum may require different methods
Quantity: multiple windows can reduce per-unit cost

For an exact price: contact us for a free quote. We measure on-site and provide a detailed estimate with no obligation.

The full process is typically 2 to 3 weeks:

Day 1–2: visit, measurements, quote
Day 3–7: approval and order, custom manufacturing
Day 10–21: delivery and installation (usually completed in one day)

Timelines can vary by season and project complexity. We commit to the agreed schedule and keep you informed throughout.

Yes. Caulking is essential and should be redone every 5 to 10 years. Benefits include:

Energy savings: can reduce heating/cooling costs by up to 20%
Water protection: prevents leaks that may lead to mold and rot
Comfort: eliminates drafts and cold spots around windows
Durability: protects frames from water damage

Signs you need recaulk: cracked, detached, hardened or discolored sealant, drafts or moisture marks.

We accept multiple payment methods:

Cash / cheque
Credit cards (Visa, Mastercard)
Interac e-transfer
Split payment (50% upon order, 50% upon installation)

For larger projects, contact us to discuss flexible options. No payment is required before you approve the quote.

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