Northampton · Northamptonshire
Misted Glass Repair in Northampton
Cloudy, streaky double glazing in Northampton is usually a failed sealed unit, and we can quote to replace it without disturbing the frame.
- NN1
- NN2
- NN3
- NN4
- NN7
- Guide from £155
About blown double glazing units in Northampton
Once the seal has failed, any argon or other insulating gas in the cavity has escaped and been replaced by ordinary damp air. The unit insulates less well than when it was new, and moisture inside can gradually leave deposits that dull the glass.
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.
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.
A sealed unit has a spacer bar around its edge filled with desiccant, a drying agent that absorbs any moisture inside the cavity. When the edge seal fails, damp air keeps getting in until the desiccant is saturated, and condensation then forms between the panes where it cannot be wiped off.
Included as standard
- Made-to-measure replacement units matching your windows
- Written quote fixing the price for the specification
- Measurement of each failed sealed unit
- Survey to confirm the mist is inside the unit
About Northampton for this job
- Postcodes covered
- NN1, NN2, NN3, NN4, NN7 and the surrounding area, including Wellingborough, Daventry and Rushden
- Coast
- Northampton is well inland, around 96 km from the nearest coast, so salt exposure is not usually a factor.
- Daylight and sun
- In Northampton the midwinter sun reaches about 14° above the horizon at noon, with roughly 7.5 hours of daylight, rising to about 61° and 16.5 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
- In flats and terraced streets, replacing misted units often means planning access, parking and carrying units up stairs. Upper-floor windows may need to be done from inside, and conservation areas may require matching bars or glass patterns.
- 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 Northampton
| 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
Toughened safety unit
Both panes toughened, for misted units in doors, beside doors or low down where safety glass is required.
Georgian bar or leaded
Decorative bars or lead designs remade to match the originals so the new unit lines up with neighbouring windows.
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 Northampton: questions
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 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.
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.
Why has condensation appeared between my double glazing panes?
Condensation between the panes means the edge seal of the sealed unit has failed. Damp air has got into the cavity, and the drying agent in the spacer bar can no longer absorb it. The cause is often age, water sitting in the frame, poor packing or strong sun on the frame. The fix is to replace the sealed unit.
Do you cover Northampton for misted glass repair?
Yes. We can quote for misted glass repair across Northampton and the surrounding Northamptonshire area, including postcode districts NN1, NN2, NN3, NN4 and NN7, and nearby Wellingborough, Daventry and Rushden. 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 Northampton
Free survey for new glazing, clear guide prices and one point of contact for every glazing job.