Clapham · Greater London
Secondary Glazing in Clapham
Is traffic noise getting through the windows of your home in Clapham? We can quote for acoustic secondary glazing tailored to each opening.
- SW4
- SW8
- SW11
- Guide from £465
About secondary glazing listed buildings in Clapham
If an existing window is relied on for escape in a fire, the secondary glazing in front of it must open easily and give enough clear opening. The surveyor checks which windows are escape windows, so the opening style and catches do not block a way out.
Secondary glazing can also add security, because an intruder would have to break through two separate windows. Laminated glass and locking catches on the secondary unit add further resistance, which is useful for ground-floor and basement windows in period properties.
A low-emissivity coating on the secondary glass reflects heat back into the room and improves the insulation of the combined window. It is a useful choice for single-glazed sash and casement windows where the originals must be kept for character or planning reasons.
Glass for secondary glazing is heavy, so the frames need firm fixings into the reveal or a supporting sub-frame. The surveyor checks that plaster, timber linings and window boards are sound enough to carry the weight, and allows for any packing needed in uneven reveals.
Included as standard
- Fitting, sealing and checking every opening panel
- Advice on opening style, glass and fire escape
- Survey of each window, reveal depth and sightlines
- Made-to-measure slim aluminium frames and glass

Working in Clapham
- Postcodes covered
- SW4, SW8, SW11 and the surrounding area, including Brixton, Chelsea and Streatham
- Coast
- Clapham is well inland, around 35 km from the nearest coast, so salt exposure is not usually a factor.
- Daylight and sun
- In Clapham 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. Secondary glazing adds an extra layer of glass, which slightly reduces daylight. Low-iron or clear low-E glass keeps light loss to a minimum, while on sunny elevations solar control glass can help reduce overheating in rooms with large windows.
- Access and setting
- Rural cottages and period homes often have single-glazed timber windows that cannot easily be replaced. Secondary glazing reduces draughts and heat loss in exposed locations, and the surveyor allows for uneven reveals and older plaster when fixing frames.
- 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 Clapham
| Typical job | Guide price inc VAT |
|---|---|
| Slider, 900 × 1200 mm | £465 – £595 |
| Slider, 1200 × 1600 mm | £665 – £845 |
| Acoustic glass, 1000 × 1400 mm | £675 – £865 |
Get a guide price for your size
Listed buildings in England need listed building consent for most changes to historic windows or glass, and conservation areas can restrict changes visible from the street. Speak to the council's conservation officer before ordering.
Choosing your secondary glazing
Horizontal sliding
Panels slide sideways, suiting wide casement windows and openings where you need regular access for cleaning or ventilation.
Acoustic laminated glass
Laminated glass with a sound-dampening interlayer, combined with a generous cavity, for properties affected by traffic, rail or aircraft noise.
Fixed panel
A non-opening unit for windows never opened, giving the most airtight seal for noise and draught reduction.
Secondary Glazing in Clapham: questions
Will secondary glazing cause condensation?
It can, if the original window is sealed tighter than the secondary unit, because warm, moist room air then gets trapped in the cavity. The secondary unit should be the more airtight of the two, and the original window should not be fully sealed. Opening the secondary panel lets room air into the cavity, so close it again afterwards.
How do I clean and look after secondary glazing?
Open or remove the panels as designed, then clean the glass with mild soapy water and a soft cloth. Wipe the aluminium frames and runners, and keep tracks free of dust so panels slide smoothly. Check seals and catches occasionally. Avoid abrasive cleaners, which can scratch coated glass.
Can I still open my original windows?
Yes, as long as the secondary glazing has an opening panel in front of the part you need to open. Sliding and hinged panels give access to the original window for ventilation and cleaning. Lift-out and fixed panels suit windows you rarely or never open.
How much noise does secondary glazing block?
Results depend on the size of the gap between the windows, the glass type and thickness, the seals and the original window. A larger cavity and acoustic laminated glass give the strongest improvement. The survey checks reveal depth and noise sources, so the specification can be tailored to the noise you are dealing with.
Do you cover Clapham for secondary glazing?
Yes. We can quote for secondary glazing across Clapham and the surrounding Greater London area, including postcode districts SW4, SW8 and SW11, and nearby Brixton, Chelsea and Streatham. 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 Clapham
Free survey for new glazing, clear guide prices and one point of contact for every glazing job.