Letchworth Garden City · Hertfordshire
Secondary Glazing in Letchworth Garden City
Single-glazed sash windows in Letchworth Garden City can stay as they are, with vertical sliding secondary glazing fitted inside to reduce draughts and cold.
- SG6
- SG5
- SG15
- Guide from £465
Secondary glazing for homes and businesses in Letchworth Garden City
Secondary glazing leaves the original window untouched and fits a second, independent window inside it. The air gap between the two works with the glass to reduce noise and heat loss. In most cases the installation can be taken out later without damaging the historic window or reveal.
Opening styles include vertical sliders that line up with sash window meeting rails, horizontal sliders for wide openings, hinged casements, lift-out panels for windows that are rarely opened, and fixed panes. The choice depends on how you use the window, cleaning access and fire escape needs.
Condensation in the gap between the two windows is reduced by making the secondary unit the more airtight of the two. The original window should not be fully sealed, so any moisture that gets into the cavity can escape outside rather than being trapped against the glass.
Low-level secondary glazing is still glazing, so the safety glazing rules for critical locations apply. In England, Approved Document K treats glass within 800mm of the floor as a critical location, so low-level secondary panes should be toughened or laminated safety glass.
What a typical job includes
- Advice on opening style, glass and fire escape
- Written quote fixing the price for the specification
- Fitting, sealing and checking every opening panel
- Removal of packaging and cleaning of new glass
About Letchworth Garden City for this job
- Postcodes covered
- SG6, SG5, SG15 and the surrounding area, including Hitchin, Stevenage and Luton
- Coast
- Letchworth Garden City is well inland, around 70 km from the nearest coast, so salt exposure is not usually a factor.
- Daylight and sun
- In Letchworth Garden City the midwinter sun reaches about 15° above the horizon at noon, with roughly 7.5 hours of daylight, rising to about 62° and 16.5 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 Letchworth Garden City
| 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
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.
Options to choose between
Low-E glass
Coated glass that reflects heat back into the room, improving insulation when the original window is single glazed.
Vertical sliding
Panels slide up and down, with meeting rails aligned to sash windows so the secondary unit is discreet from inside and outside.
Horizontal sliding
Panels slide sideways, suiting wide casement windows and openings where you need regular access for cleaning or ventilation.
Secondary Glazing in Letchworth Garden City: questions
Is secondary glazing as good as double glazing?
It depends on the goal. For noise, secondary glazing is often more effective, because the wider gap between the two windows reduces sound better than the narrow cavity of a sealed unit. For heat, a well-sealed secondary unit with low-E glass significantly improves a single-glazed window. It also keeps original windows, which matters in listed buildings.
Is secondary glazing suitable for rented homes and flats?
Yes. Secondary glazing is fitted inside, so it often avoids the external changes that leases, freeholders or planning rules restrict. It can be removed later with limited making good. Leaseholders should still check their lease for any rules on internal alterations, and landlords should check escape routes are not affected.
Which opening style should I choose?
Choose based on how you use the window. Vertical sliders suit sash windows and keep meeting rails aligned. Horizontal sliders suit wide windows. Hinged panels give full access for cleaning and escape. Lift-out and fixed panels suit windows that are rarely or never opened, and give the tightest seal for noise.
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.
Do you cover Letchworth Garden City for secondary glazing?
Yes. We can quote for secondary glazing across Letchworth Garden City and the surrounding Hertfordshire area, including postcode districts SG6, SG5 and SG15, and nearby Hitchin, Stevenage and Luton. 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 Letchworth Garden City
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