Chiswick · Greater London
Misted Glass Repair in Chiswick
Cloudy, streaky double glazing in Chiswick is usually a failed sealed unit, and we can quote to replace it without disturbing the frame.
- W4
- W3
- W6
- Guide from £155
Chiswick: condensation between panes
If the misted unit is in a door, beside a door or low down near the floor, the replacement should be safety glass. In England, Approved Document K sets out these critical locations, and the replacement unit should meet them even if the original glass did not.
Some services offer to drill the glass, flush the cavity and add a vent instead of replacing the unit. This can improve the look, but it does not restore the original seal, and any gas fill that helped the unit insulate has already been lost. Replacement restores a sealed cavity.
Replacing a misted unit is usually a short job per window once the new unit has been made. The old unit is lifted out, the frame rebate and drainage cleaned, and the new unit set on packers so the weight is supported and any opening sash stays square.
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.
What a typical job includes
- Written quote fixing the price for the specification
- Survey to confirm the mist is inside the unit
- Fitting on packers with drainage slots checked
- Removal of old units and cleaning of rebates

Chiswick at a glance
- Postcodes covered
- W4, W3, W6 and the surrounding area, including Acton, Barnes and Hammersmith
- Coast
- Chiswick is well inland, around 44 km from the nearest coast, so salt exposure is not usually a factor.
- Daylight and sun
- In Chiswick 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 Chiswick
| 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.
What you can choose
Georgian bar or leaded
Decorative bars or lead designs remade to match the originals so the new unit lines up with neighbouring windows.
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.
Misted Glass Repair in Chiswick: 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.
Can you clean the inside of a misted double glazing unit?
Not without breaking the seal. Some firms drill the glass, flush the cavity and fit a small vent, which can clear the mist for a while. It does not restore an airtight seal or gas fill, and white staining may not fully clear. Replacing the unit is the reliable way to restore a clear, sealed cavity.
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.
Can misted double glazing be fixed without replacing the window?
Yes. In most cases only the sealed unit needs replacing, not the frame. The glazier removes the beads, lifts out the misted unit and fits a new one made to the same thickness. Your frames, hinges, handles and locks stay as they are, provided they are in good condition, which the glazier checks at the survey.
Do you cover Chiswick for misted glass repair?
Yes. We can quote for misted glass repair across Chiswick and the surrounding Greater London area, including postcode districts W4, W3 and W6, and nearby Acton, Barnes and Hammersmith. Start with your postcode on the quote form and a glazier will arrange a free survey before giving you a written quote.
More glazing in Chiswick
Misted Glass Repair nearby
Get a written quote in Chiswick
Free survey for new glazing, clear guide prices and one point of contact for every glazing job.