Glass-only replacement · Wales
Triple glazed sealed unit replacement in South Glamorgan
From Cardiff to Llantwit Major, we arrange triple glazed replacement sealed units for homes across South Glamorgan, with every quote fixed for the specification shown.
Triple units for frames that can take them; better double units when they cannot. Sealed unit replacement means changing only the glass in an existing frame.
Guide prices across South Glamorgan
Small unit
up to about 0.6 m2, frame checked first
£145 – £195inc VAT · £120 – £160 ex VAT
- Triple unit made to measure
- Old unit removed and recycled
- New beads and glazing packers where needed
Medium unit
about 0.6 to 1.2 m2
£195 – £245inc VAT · £160 – £205 ex VAT
- Triple unit made to measure
- Old unit removed and recycled
- New beads and glazing packers where needed
Large unit
about 1.2 to 2 m2
£295 – £395inc VAT · £245 – £330 ex VAT
- Triple unit made to measure
- Old unit removed and recycled
- New beads and glazing packers where needed
Guide prices, supply and fit. The written quote after your survey fixes the price for the specification shown; anything extra is agreed with you first.
Towns in South Glamorgan
Rules in Wales
The rules for replacement windows in Wales are set by Approved Document L for Wales (2022 edition, with 2024 amendments): 1.4 W/m²K, or a Window Energy Rating of band B or better. As in England, replacement windows are a controlled fitting: a competent person scheme installer self-certifies the work, or building control approves it.
Planning: Householder permitted development rules do not cover flats, and councils can remove rights with Article 4 directions. Listed buildings need listed building consent. Check with your council before changing the style or material.
How it works
We start with a survey, not a sales pitch: measurements, the structure above any bays, trickle-vent needs and escape windows. The quote that follows fixes the price, and anything unexpected on the day is agreed with you first.
- Every opening measured, including escape and vent needs
- Frames rated for the weight of triple glass
- Old windows removed and taken away
- Each opening closed up the same day
Questions
Can I put triple glazing in my existing windows?
Usually not in a way that helps. Most frames take up to about 28 mm units; a triple unit that thin performs about the same as, or worse than, good double glazing. We check your frames before recommending anything.
Will heavier glass damage my hinges?
It can. Triple units are about 50% heavier, so hinges and packers are checked and upgraded where needed.
How much does a triple glazed sealed unit cost?
Where a frame can take one, our guide starts at £145 fitted for a small unit, inc VAT. Published UK figures of about £90 to £220 per unit are mostly for double units; triple units cost more.
Do you cover all of South Glamorgan?
We arrange surveys and fitting across South Glamorgan.
Do I need permission for triple glazed replacement sealed units in Wales?
In Wales, householder rules do not cover flats, councils can use Article 4 directions, and listed buildings need consent.
Glass-only replacement in nearby areas of Wales
Other products in South Glamorgan
- uPVC windows
- Aluminium windows
- Timber windows
- Alu-clad timber windows
- Casement windows
- Flush casement windows
- Tilt and turn windows
- Sash windows
- Bay and bow windows
- Fixed and picture windows
- Composite front doors
- French doors
- Sliding patio doors
- Bifold doors
- Acoustic triple glazing
- Security glazing
- Whole-house replacement
- New builds and self-builds
- Period homes and conservation areas
- Flats and apartments
- Passivhaus and EnerPHit
Glass-only replacement across South Glamorgan
Written quote fixed for the specification, after a free survey. Building Regulations sign-off by a competent person scheme installer or building control, as the law requires in Wales.