Glass-only replacement · England
Triple glazed sealed unit replacement in Merseyside
Triple glazed replacement sealed units across Merseyside: free survey, written fixed quote, and fitting by installation teams working for us. Towns we cover include Liverpool, Birkenhead and Halewood.

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 Merseyside
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 Merseyside
- Liverpool
- Birkenhead
- St Helens
- Southport
- Wallasey
- Bootle
- Bebington
- Huyton
- Kirkby
- Prescot
- Heswall
- Maghull
- Newton-le-Willows
- Formby
- Litherland
- Speke
- Garston
- Halewood
Rules in England
The rules for replacement windows in England are set by Approved Document L (2021 edition, with 2023 amendments): 1.4 W/m²K, or a Window Energy Rating of band B or better. Replacement windows are a controlled fitting. A competent person scheme installer (such as FENSA or Certass) self-certifies the work and notifies the council within 30 days; otherwise a building control body approves it.
Planning: Replacing windows on a house is normally permitted development if the new ones look similar. New upper-floor windows in a side wall must be obscure glazed and fixed, or open only above 1.7 m. Flats and maisonettes have no householder permitted development rights, so a change that alters their appearance needs planning permission. An Article 4 direction in a conservation area may mean permission is needed, and listed buildings need listed building consent.
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.
- Free survey and a written quote fixed for the specification
- Glass build-up and whole-window U-value on every quote
- Written handover pack at the end of the job
- Guarantees on frames, units and fitting in writing
Questions
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.
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.
Do you cover all of Merseyside?
We arrange surveys and fitting across Merseyside.
Do I need permission for triple glazed replacement sealed units in England?
In England, like-for-like replacements on a house are normally permitted development; flats need permission if the change alters their appearance, Article 4 areas may need permission, and listed buildings need listed building consent.
Glass-only replacement in nearby areas of England
- Cheshire
- Greater Manchester
- Lancashire
- Shropshire
- Staffordshire
- West Yorkshire
- Derbyshire
- South Yorkshire
- Cumbria
- West Midlands
Other products in Merseyside
- 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 Merseyside
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 England.
