Windsor · Berkshire
Misted Glass Repair in Windsor
Our glaziers cover Windsor for misted window repairs, checking frames and drainage at the survey so the new sealed units are fitted correctly.
- SL4
- Guide from £155
Windsor: blown double glazing units
Condensation on the room-side surface of the glass is not the same problem. It usually comes from humid indoor air meeting a cold pane and can be wiped away. Only mist trapped between the two panes means the sealed unit itself has failed and needs replacing.
Check the paperwork for your windows before booking. Many sealed units come with a manufacturer guarantee against misting, and if your windows are still covered, the original installer or manufacturer may be responsible for replacing the failed unit under its terms.
Common causes of seal failure include water sitting in the frame rebate because drainage holes are blocked, units fitted without correct packers, strong sun on dark frames, and age. Clearing the drainage slots in the frame helps protect the new unit from the same problem.
A misted unit is a good opportunity to upgrade an older plain glass unit to one with a low-emissivity coating and gas fill. The new unit reduces heat loss through the glass and keeps the room-side pane warmer, without any change to the frame.
What you get
- Measurement of each failed sealed unit
- Survey to confirm the mist is inside the unit
- Written quote fixing the price for the specification
- Removal of old units and cleaning of rebates

Local details for Windsor
- Postcodes covered
- SL4 and the surrounding area, including Slough, Egham and Staines
- Coast
- Windsor is well inland, around 67 km from the nearest coast, so salt exposure is not usually a factor.
- Daylight and sun
- In Windsor the midwinter sun reaches about 15° above the horizon at noon, with roughly 7.6 hours of daylight, rising to about 62° and 16.4 hours in midsummer. Units on sunny south and west elevations go through bigger daily temperature swings, which stresses the edge seal over time. In colder, darker months, mist between the panes is often most visible, so the survey is a good time to confirm failure.
- Access and setting
- Older rural homes may have timber frames or units of non-standard sizes, so careful measuring at the survey matters. Exposed sites with driving rain place more strain on seals, and the glazier checks frame drainage and bead condition before fitting.
- Rules in England
- Approved Document K requires safety glass in critical locations in England: glazing in doors and in side panels within 300 mm of a door, up to 1500 mm above floor level, and any glazing in walls or partitions up to 800 mm above floor level.
Guide prices in Windsor
| Typical job | Guide price inc VAT |
|---|---|
| One misted unit, 600 × 900 mm | £155 – £195 |
| Two misted units, 600 × 900 mm | £305 – £395 |
| Four misted units, 600 × 1100 mm | £685 – £875 |
| Misted unit in a door, toughened | £305 – £385 |
Get a guide price for your size
Approved Document L sets the minimum energy performance for replacement windows and doors in existing homes in England: a U-value of 1.4 W/m²K, or Window Energy Rating band B for windows; doors can instead meet a Door Set Energy Rating (band B, or band C for doors more than 60% glazed); rooflights need 2.2 W/m²K.
Choosing your misted glass repair
Laminated safety unit
A unit with laminated glass that holds together if broken, useful for ground-floor security and safety in critical locations.
Toughened safety unit
Both panes toughened, for misted units in doors, beside doors or low down where safety glass is required.
Like-for-like clear unit
A direct replacement matching the thickness and look of the original unit, for windows where no change in performance is needed.
Misted Glass Repair in Windsor: questions
Is it worth replacing misted units or should I get new windows?
If the frames are sound, square and the hinges and locks work, replacing only the misted units is usually the more economical option. New windows make more sense if the frames are rotten, warped, draughty or hard to open. The glazier checks the frames at the survey and the quote will say if replacing units is not good value.
Will a new unit match my other windows?
It can. The glazier records the unit thickness, spacer bar colour, any Georgian bars or leaded designs, and the obscure glass pattern if there is one. Most details can be matched closely. If an obscure pattern has been discontinued, the quote offers the closest available alternative so you can decide before anything is ordered.
How much does it cost to replace a misted sealed unit?
The cost depends on the size of the unit, the glass type, any Georgian bars, leaded or obscure features, how many units are done together, and access to the window. Larger units, safety glass and upper-floor windows cost more. See the guide prices for typical sizes, then get a written quote for your exact windows.
Are misted units covered by a guarantee?
Often they are, for a period after installation. Many sealed unit manufacturers guarantee against misting, and the terms are set out in the paperwork from the original installer. If your units are still covered, contact that installer first. Units we supply carry manufacturer guarantees, and the terms are confirmed in writing with your quote.
Do you cover Windsor for misted glass repair?
Yes. We can quote for misted glass repair across Windsor and the surrounding Berkshire area, including postcode districts SL4, and nearby Slough, Egham and Staines. Start with your postcode on the quote form and a glazier will arrange a free survey before giving you a written quote.
Get a written quote in Windsor
Free survey for new glazing, clear guide prices and one point of contact for every glazing job.