Gillingham · Kent
Secondary Glazing in Gillingham
Single-glazed sash windows in Gillingham can stay as they are, with vertical sliding secondary glazing fitted inside to reduce draughts and cold.
- ME7
- ME8
- Guide from £465
Internal secondary windows for homes and businesses in Gillingham
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.
Owners of listed buildings should seek listed building consent before installing secondary glazing, as the requirements depend on the building and the council. Secondary glazing is often seen as a minimal, reversible change, but carrying out works that need consent without it is a criminal offence.
Slim aluminium frames are designed to sit within the window reveal and line up with the original glazing bars or meeting rails. Matching sightlines keeps the secondary unit discreet from outside and inside, which matters for period homes and conservation areas.
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's included
- Removal of packaging and cleaning of new glass
- Advice on opening style, glass and fire escape
- Made-to-measure slim aluminium frames and glass
- Survey of each window, reveal depth and sightlines

Working in Gillingham
- Postcodes covered
- ME7, ME8 and the surrounding area, including Chatham, Rochester and Strood
- Coast
- Gillingham is about 2 km from the coast or a tidal estuary, so salt air and wind-driven rain are worth planning for. Coastal properties often have older windows exposed to wind-driven rain and draughts. Secondary glazing adds a sealed inner layer that reduces draughts and cold, while the original window keeps out the weather and its condition is protected from inside.
- Daylight and sun
- In Gillingham 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
- In city centres and busy streets, acoustic secondary glazing is a common response to traffic, rail and nightlife noise. Flats, listed buildings and conservation areas often limit external changes, which makes internal secondary glazing a practical option.
- 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 Gillingham
| 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.
Choosing your secondary glazing
Low-E glass
Coated glass that reflects heat back into the room, improving insulation when the original window is single glazed.
Lift-out panel
A lightweight panel that lifts out of its frame, for windows rarely opened, giving a slim and economical secondary unit.
Vertical sliding
Panels slide up and down, with meeting rails aligned to sash windows so the secondary unit is discreet from inside and outside.
Secondary Glazing in Gillingham: questions
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.
Do I need permission for secondary glazing on a listed building?
You should seek listed building consent from the council's planning department before installing secondary glazing on a listed building. Secondary glazing is often seen as a reversible, low-impact change, but consent requirements depend on the building. Carrying out works that need consent without it is a criminal offence. If your home is not listed but is in a conservation area, check with the council if you are unsure.
How much does secondary glazing cost?
The cost depends on the size and number of windows, the opening style, the type of glass, any arched or shaped heads, reveal depth and access. Acoustic and low-E glass cost more than standard clear glass, and shaped frames need more work. See the guide prices for typical windows, then get a written quote after the survey.
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.
Do you cover Gillingham for secondary glazing?
Yes. We can quote for secondary glazing across Gillingham and the surrounding Kent area, including postcode districts ME7 and ME8, and nearby Chatham, Rochester and Strood. 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 Gillingham
Free survey for new glazing, clear guide prices and one point of contact for every glazing job.