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Same-Week Dispatch
4.3/5 from 27+ reviews

Misty Windows

Replacement sealed units for misty and fogged double glazing. When the seal fails and moisture gets trapped between the panes, the only fix is a new unit. We manufacture exact-size replacements with same-week dispatch — specify the glass, choose the performance level, and order.
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FENSA Registered
BS EN 1279 Certified
Nationwide Delivery
Same-Week Dispatch
4.3/5 rating from 27+ reviews
Trade Pricing Available

A misted sealed unit means the perimeter seal has failed and the insulating gas has escaped. Here's how to specify the correct replacement unit for your customer's window.

Expert Glazing, Done Right

We're not a national call centre. We're local glaziers who take pride in every job.

Exact-Size Manufacturing

Every unit made to your measurements — no trimming, no shimming. Tight tolerances for clean bead engagement and proper gasket compression. Measure once, fit once.

Upgrade the Specification

The original unit was likely basic clear glass with air fill. Replace with Low-E coated glass and argon fill for a measurable thermal upgrade — U-values from 1.1 W/m²K.

Match Any Configuration

We replicate any existing unit: 20mm, 24mm, 28mm, or 32mm overall thickness. Clear, tinted, obscure, or decorative glass. Georgian bars, leaded effect, or plain.

Same-Week on Standard Sizes

Standard rectangular units in common thicknesses dispatch within the same working week. Bespoke sizes and special glass types within 5-7 working days.

10-Year Guarantee

Every replacement unit carries our 10-year warranty against seal failure and gas retention loss. If it mists again within warranty, we replace it free.

Help your customers understand what's happened and why replacement is the only effective solution. These are the telltale signs of sealed unit failure.

Signs Your Double Glazing Needs Attention

Catching problems early saves money and prevents bigger issues. Here are the telltale signs your windows need professional attention.

⚠️ Noticed any of these issues? Do not wait - small problems become expensive repairs. Get a free assessment today.

Expert Knowledge

Misty Windows: Specifying the Right Replacement Unit

Why Sealed Units Fail

Every double glazed sealed unit has a designed lifespan — typically 20-25 years for quality units. Failure occurs when the perimeter seal (usually polysulphide or silicone) degrades, allowing moisture to enter the cavity and insulating gas to escape. UV exposure, thermal cycling, and manufacturing quality all influence lifespan.

Once the seal fails, the desiccant in the spacer bar absorbs moisture until it's saturated. After that point, condensation forms between the panes whenever the temperature drops. There is no repair — drilling, venting, or injecting desiccant are temporary fixes that don't restore the thermal seal. Replacement is the only permanent solution.

Measuring for Replacement

For misty window units, measure width and height at the glass line (inside the beads) to the nearest millimetre. Measure the overall unit thickness from face to face. Common configurations:

20mm units (4-12-4): Found in older installations and slim frames.
24mm units (4-16-4): The most common domestic configuration.
28mm units (4-20-4): Increasingly standard in newer frames.
32mm units: Triple glazed or enhanced double glazed specifications.

Choosing the Right Specification

A misty window replacement is the ideal time to upgrade the glass specification. Most failed units date from 10-20 years ago when basic float glass with air fill was standard. Today's options deliver dramatically better performance:

Low-E coating + argon fill: Reduces the U-value from approximately 2.8 W/m²K (old clear glass) to 1.1 W/m²K. Your customer will feel the difference immediately — warmer glass surface, less condensation on the room side, lower heating bills.

Acoustic glass: If the window faces a road, railway, or flight path, recommend an asymmetric configuration (e.g. 6.4mm laminated outer, 16mm cavity, 4mm inner). Reduces noise by up to 45dB.

Safety glass: Required for low-level glazing (below 800mm), doors, and windows adjacent to doors. Toughened or laminated to BS EN 12600.

A misty window replacement costs your customer significantly less than a full window replacement. Position the specification upgrade as a modest premium for a major performance improvement. The price difference between basic clear glass and A-rated Low-E with argon is typically £15-25 per unit — but the energy saving and comfort improvement is substantial.

Simple ordering for trade professionals. One unit or fifty — same process, same quality, same turnaround.

How Our Service Works

From first contact to finished job, we make the whole process straightforward and stress-free.

Measure the Failed Unit

Width, height, and overall thickness at the glass line. Note glass type if visible (clear, Low-E, tinted, obscure) and any features (Georgian bars, safety marking). Take a photo if unsure.

Choose Your Specification

Like-for-like replacement or upgrade? We'll quote both options so you can present the choice to your customer. Low-E + argon is the most popular upgrade.

Place the Order

Via our trade portal, email, or phone. We confirm specification and pricing — usually within the hour. Trade account holders get 30-day terms.

We Deliver, You Fit

Standard sizes dispatched same-week. Tracked delivery to your workshop or direct to site. Secure packaging with edge protection. You fit and invoice your customer.
Every option you need to quote and complete misty window repair jobs — from basic like-for-like to premium upgrades.

What We Can Help With

From quick repairs to complete replacements, we handle all residential and commercial glazing needs.

Standard Clear Replacement

Like-for-like clear glass sealed units in all standard thicknesses. The budget option for price-sensitive customers who just want clear glass again.

Energy Efficient Upgrade

Low-E coated glass with argon fill. U-values from 1.1 W/m²K — a genuine upgrade that reduces energy bills and eliminates room-side condensation.

Acoustic Units

Asymmetric pane configurations for noise reduction. Ideal when the failed unit faces a road or other noise source. Solve two problems with one replacement.

Obscure & Privacy

Replacement obscure glass units for bathrooms and privacy-sensitive windows. All standard patterns available — match the existing or change to a different pattern.

Georgian Bar Units

Internal Georgian bars in white, gold, or woodgrain. Replicate traditional styling when replacing a failed decorative unit.

Toughened & Safety

BS EN 12600 safety glass for low-level windows, doors, and windows adjacent to doors. Toughened, laminated, or toughened-laminated options.

Not sure what you need? No problem - we will assess and advise. No obligation, no pressure.

Trusted by Tradespeople & Homeowners

What Our Customers Say

4.3 ★ from 27 Google reviews

  • 15+

    Years in Business

  • 10,000+

    Sealed Units Supplied

  • 27+

    Google reviews

  • ★★★★★
    Huge shout-out to Ollie and the team! ⭐⭐⭐⭐⭐ ​Our patio door went from being completely stuck and impossible to lock to sliding like a dream. Ollie diagnosed the issue (collapsed wheels) and his team squeezed us in despite a packed schedule. ​The difference is night and day—it literally feels like it’s sliding on air now. If you’re looking for reliable, expert servi...

    Susan Passmore

  • ★★★★★
    We had glass panes and hinges replaced throughout the house and a new set of french doors. Ollie and everyone that came to fit were friendly, professional, tidy and considerate. The work has been carried out to excellent quality - especially the french doors which look fantastic.

    Lucy Bennett

  • ★★★★
    Complex issue with a broken non-standard hinge on 1st floor window. Ollie was the only one of over 10 other firms I contacted who said they could do the job. It took a while, but Ollie managed to source a replacement part and completed the job to a high standard. Very happy with the work done and have asked him to do another job following the good experience.

    Dave Edwards

Common questions about ordering replacement sealed units for misty windows.

Frequently Asked Questions

Everything you need to know about our double glazing repair and replacement services across the South West.

  • No. Once the perimeter seal has failed, the unit cannot be permanently repaired. Drilling and venting methods are temporary and compromise the unit's thermal performance. Replacement is the only permanent solution.

  • No — just the sealed unit. The frame, hinges, handles, and hardware all stay. The sealed unit is removed from the beads and a new one fitted in its place. It's a 20-40 minute job per window for a competent installer.

  • Yes — and we recommend it. Most failed units are 15-20 years old with basic clear glass. Replacing with Low-E + argon costs only £15-25 more per unit but delivers significantly better thermal performance.

  • Same-week dispatch for standard rectangular units. 5-7 working days for non-standard sizes or specialist glass types. Rush orders available — call our trade team.

  • No minimum. One unit for a single repair job gets the same quality and turnaround as a bulk order.

  • 10-year warranty on seal integrity and gas retention. If the unit mists within warranty, we replace it free of charge.

Explore More

Related Services

We offer a complete range of glazing services across Bristol. See how else we can help.

Double Glazing Repairs

Full range of replacement sealed units for all double glazing repair work.
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Failed Seals

Replacement units for windows with failed perimeter seals.
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Double Glazing Units

Browse our complete double glazing range — all sizes and specifications.
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Energy Efficient Glass

A-rated sealed units with Low-E coating and argon fill.
Learn more

Order Misty Window Replacements

Get your free, no-obligation quote today. Most quotes delivered within 24 hours.

Request Free Quote Call 0117 330 3057

Prefer to talk? Call us on 0117 330 3057