Glass-only replacement · Wales
Triple glazed sealed unit replacement in Mid Glamorgan
Triple glazed replacement sealed units across Mid Glamorgan: free survey, written fixed quote, and fitting by installation teams working for us. Towns we cover include Rhondda, Tonypandy and Maesteg.

Straight advice on swapping glass only, and when it is worth it. Sealed unit replacement means changing only the glass in an existing frame.
Guide prices across Mid 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 Mid 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.
Before ordering: 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
After the free survey you get a written quote naming the frame system, the glass build-up and the whole-window U-value for every item. Windows are made to order, then fitted, sealed and made good, one opening at a time.
- 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.
Why are my windows misting between the panes?
The seal around the unit has failed and moist air has got in. Only replacing the unit fixes it.
Will heavier glass damage my hinges?
It can. Triple units are about 50% heavier, so hinges and packers are checked and upgraded where needed.
Do you cover all of Mid Glamorgan?
We arrange surveys and fitting across Mid 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 Mid 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 Mid 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.
