Cardiff · South Glamorgan
Secondary Glazing in Cardiff
Where planning or lease rules limit changes to the outside, secondary glazing in Cardiff offers an internal option that can be removed later.
- CF10
- CF11
- CF24
- Guide from £465
Secondary glazing for sash windows across Cardiff
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.
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.
The price of secondary glazing depends on the size and number of windows, the opening style, the glass specification, any shaped or arched heads, reveal depth and condition, and access. Acoustic laminated glass and shaped frames cost more than standard clear glass in rectangular frames.
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.
Included as standard
- Fitting, sealing and checking every opening panel
- Removal of packaging and cleaning of new glass
- Made-to-measure slim aluminium frames and glass
- Advice on opening style, glass and fire escape
Local details for Cardiff
- Postcodes covered
- CF10, CF11, CF24 and the surrounding area, including Penarth, Caerphilly and Barry
- Coast
- Cardiff is about 3 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 Cardiff 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 Wales
- In Wales, Approved Document N covers safety glazing: safety glass is needed in and around doors and in low-level glazing where people could walk into it.
Guide prices in Cardiff
| 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
Wales sets its own energy standards in the Welsh Approved Document L. Replacement windows, doors and rooflights must meet the limiting values set there, which your quote will reference.
Choosing your secondary glazing
Fixed panel
A non-opening unit for windows never opened, giving the most airtight seal for noise and draught reduction.
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.
Secondary Glazing in Cardiff: questions
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.
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.
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.
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.
Do you cover Cardiff for secondary glazing?
Yes. We can quote for secondary glazing across Cardiff and the surrounding South Glamorgan area, including postcode districts CF10, CF11 and CF24, and nearby Penarth, Caerphilly and Barry. 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 Cardiff
Free survey for new glazing, clear guide prices and one point of contact for every glazing job.