Glass & repairs
Replacement Glass & Sealed Units
Replacement glass is new glass or a new sealed unit fitted into an existing window, door or screen frame, without replacing the frame itself. It is needed when a pane is cracked, broken, misted or scratched, or when the glass needs upgrading to safety, obscure, acoustic or more energy-efficient glass.
- Guide from £135
- Free survey
- Written quote
- UK-wide
- Free survey for new glazingMeasured on site before anything is made
- Written quoteThe price is fixed for the specification shown
- Every glazing jobGlass, windows, doors and commercial
- UK-wide coverEngland, Wales, Scotland and Northern Ireland
- Guarantee terms in writingSet out with every quote
How our replacement glass service works
We replace single panes and double or triple glazed sealed units in existing uPVC, aluminium, timber and composite frames, so you keep the windows and doors you already have. A glazier surveys the opening, checks the frame and beading, measures the unit and confirms the glass the location needs, including safety glass where the rules call for it. You then get a written quote that fixes the price for the specification shown. The new glass is made to order, and on the fitting visit our glaziers remove the old pane, set the new unit on packers, refit the beads and clean up. The old glass is taken away. Options include toughened, laminated, obscure, acoustic, low-E and Georgian bar units.
What's included
- Survey and measurement of the existing glass or unit
- Written quote fixing the price for the specification
- Made-to-measure glass or sealed unit to suit the frame
- Removal of the old pane and cleaning of the rebate
- Fitting on glazing packers with the beads refitted
- Removal of old glass and packaging from site
When you might need replacement glass
- A pane is cracked, chipped or broken but the frame is sound
- Glass in a door or low panel is not marked as safety glass
- You want obscure glass in a bathroom or front door
- Old plain glass units need upgrading in existing frames
- Scratches or etching on the glass spoil the view
Guide prices
| Typical job | Guide price inc VAT |
|---|---|
| Small double glazed unit, 500 × 700 mm | £135 – £175 |
| Standard unit, 600 × 900 mm | £165 – £205 |
| Large unit, 1200 × 1200 mm | £285 – £365 |
| Toughened unit for a door, 750 × 1800 mm | £345 – £435 |
| Triple glazed unit, 600 × 900 mm | £235 – £305 |
Options to choose between
Standard double glazed unit
Two panes of float glass with a sealed cavity, suitable where safety glass is not required and no special performance is needed.
Low-E energy unit
A coated pane and gas-filled cavity that reduce heat loss through the glass compared with older plain float glass units.
Toughened safety glass
Heat-treated glass that breaks into small, relatively blunt pieces, used in doors, low-level panes and other critical locations.
Laminated glass
Two sheets of glass bonded to an interlayer that holds the pieces in place if it breaks, adding safety and security.
Obscure patterned glass
Textured glass for bathrooms, hallways and doors, available in several patterns that give different levels of privacy.
Acoustic laminated glass
Laminated glass with a sound-dampening interlayer, often combined with unequal pane thicknesses to reduce traffic and street noise.
Georgian bar or leaded unit
Decorative bars or lead designs inside or on the glass, matched to existing windows for a consistent look across the property.
Triple glazed unit
Three panes and two cavities for extra insulation, where the frame's rebate is deep enough to take the thicker unit.
Good to know about replacement glass
Sealed units are made to measure, so the glazier records the width, height and overall thickness of the existing unit rather than the frame opening. The new unit has to match that thickness to sit correctly in the rebate and take the original beads, otherwise the seal and security of the pane suffer.
In England, Approved Document K treats glass in a door or within 300mm of a door edge, up to 1500mm above the floor, and any other glass within 800mm of the floor as critical locations. Replacement glass in these areas should be safety glass, even where the old pane was not.
When a double glazed unit sits in a critical location, both panes need to be safety glass, not just the one facing the room. A unit with toughened glass on one side and ordinary float glass on the other does not give safe breakage from both directions.
Safety glass should carry a permanent mark, usually etched in one corner, that stays visible once the glass is fitted. The mark identifies the maker or supplier and the standard it meets, such as BS EN 12150 for toughened glass or a BS EN 12600 impact class.
Swapping glass in an existing frame is normally treated as a repair rather than notifiable building work in England. Replacing the whole frame and opening parts is different and usually needs to be notified, either through building control or a competent person scheme such as FENSA or Certass.
Older sealed units often have plain float glass on both sides. A replacement unit can use a low-emissivity coated pane and a gas-filled cavity, which reduces heat loss through the glass without changing the frame. The coating faces into the cavity and is not noticeable in normal use.
Acoustic laminated glass uses a special interlayer that dampens sound passing through the pane. Using two different glass thicknesses in a sealed unit also helps, because each pane resonates at a different frequency. Both can be fitted in an existing frame, though the frame and its seals also affect how much noise gets through.
Units with Georgian bars or leaded designs can be remade to match the originals. The glazier notes the bar width, colour and layout, or the lead pattern, so the new unit lines up with neighbouring windows. Bars fitted inside the cavity are protected from dirt and need no separate cleaning.
The price of replacement glass depends mainly on the size of the pane, the glass type and thickness, whether it is a single pane or sealed unit, special features such as bars or leaded designs, and access. Upper-floor panes that need ladders, towers or extra hands cost more to fit.
Fitting a replacement unit is usually a short visit per window once the glass has been made. The beads are eased out, the old unit lifted out, the rebate cleaned, and the new unit set on glazing packers to support its weight and keep any opening sash square before the beads go back.
Many modern windows are internally beaded, which makes it harder to remove glass from outside. If your windows have external beads, ask about security glazing tape or clips when the glass is replaced, as these make it more difficult for beads to be prised off from outside.
Before replacing glass, the glazier checks the frame for rot, cracks, failed hinges and worn seals. If the frame itself is failing, new glass may not be good value, and the quote will say so, so you can decide between glass only, repairs to the frame or a new window.
Rules and regulations
Building regulations differ between the four UK nations. Here is what usually applies to replacement glass; your written quote confirms the detail for your property.
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.
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.
Listed buildings in England need listed building consent for most changes to historic windows or glass, and conservation areas can restrict changes visible from the street. Speak to the council's conservation officer before ordering.
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.
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.
Listed buildings in Wales need listed building consent for most changes to historic windows; Cadw publishes guidance on looking after traditional windows.
Scotland
Section 4 (Safety) of the Scottish Technical Handbooks covers glazing that people could collide with, such as glass in and beside doors and low-level glazing, where safety glass is needed.
Section 6 (Energy) of the Scottish Technical Handbooks sets the thermal performance that replacement windows, doors and rooflights should achieve.
Listed buildings in Scotland need listed building consent for most changes to historic windows; Historic Environment Scotland publishes guidance on traditional windows.
Northern Ireland
Technical Booklet V covers safety glazing in Northern Ireland, including glass in and around doors and low-level glazing where people could walk into it.
Technical Booklet F1 sets the energy performance that replacement windows, doors and rooflights need to meet in Northern Ireland.
Listed buildings in Northern Ireland need listed building consent for most changes to historic windows.
What happens next
Tell us about the job
Use the quote form, call, WhatsApp or live chat. Photos and rough sizes help.
Survey and measure
A glazier visits, checks the opening and measures. For simple glass swaps this is often done on the same visit as fitting.
Written quote
You get a written quote with the specification, price and guarantee terms. Nothing is ordered until you agree.
Made and fitted
Glass, frames or panels are made to size and fitted. We tidy up and take the old glass away.
Replacement Glass questions
Can you replace just the glass without changing the window frame?
Yes. In most uPVC, aluminium and timber windows the glass or sealed unit can be removed and replaced on its own, keeping the existing frame, hinges and locks. The glazier checks the frame is in good condition first. If the frame is rotten, warped or damaged, the quote will say so, so you can decide whether glass only is still worth doing.
What affects the cost of replacement glass?
The main factors are the size of the pane, the glass type and thickness, and whether it is a single pane or a sealed unit. Toughened, laminated, acoustic and decorative units cost more than standard float glass. Access also matters, as upper-floor or awkward panes take longer to fit safely. See the guide prices for typical sizes, then get a written quote for your exact job.
How long does it take to get replacement glass fitted?
There are usually two stages: a survey to measure, then a fitting visit once the glass has been made. Toughened glass and sealed units are manufactured to order, so they cannot be cut from stock while the glazier waits. Fitting itself usually takes a short time per window. Your quote will set out when the glass is expected, and we will tell you honestly when a glazier can attend.
Do I need safety glass in my replacement window?
You do if the glass is in a critical location. In England, that means glass in doors and within 300mm of a door edge, up to 1500mm above floor level, and other glass within 800mm of the floor. Elsewhere in the UK the rules are similar, but the detail differs between nations. The glazier checks each location at the survey.
Does replacing window glass need building regulations approval?
Replacing only the glass in an existing frame is normally treated as a repair in England and does not need to be notified. Replacing the whole window is different and must go through building control or a competent person scheme. Even for glass-only work, safety glass should be used in critical locations, and the detail of the rules differs between UK nations.
Can you match obscure glass to my other windows?
Usually, yes. Obscure glass is made in many patterns, and the glazier can often identify yours from a photo or at the survey. Some older patterns are no longer made. If yours has been discontinued, the quote will offer the closest current pattern, or you can replace a matching set of panes so they all look the same.
Should I upgrade to low-E glass when replacing a unit?
If the existing unit is plain float glass, a low-emissivity unit is worth considering because it reduces heat loss through the glass and keeps the inner pane warmer, which can reduce condensation on the room side. It fits the same frame, provided the overall thickness matches. The quote can show standard and low-E options side by side.
What is the difference between toughened and laminated replacement glass?
Toughened glass is heat treated so that, if it breaks, it crumbles into small, relatively blunt pieces and leaves the opening empty. Laminated glass has a plastic interlayer between two sheets that holds the pieces together, so the pane stays in the frame. Both count as safety glass when classified to the relevant standard, and laminated also helps with security and noise.
Can I replace a sealed unit myself?
Single panes in simple frames are sometimes replaced by confident DIYers, but sealed units and safety glass carry risks. A unit that is not packed correctly can make an opening sash drop or crack under load, and handling large panes is hazardous. A glazier also checks whether safety glass is required and that the new glass carries the correct marking.
What guarantee comes with replacement glass?
Manufacturer guarantees apply to new sealed units and glass, and the terms are confirmed in writing. Guarantee terms for the fitting are set out in writing with your quote. Keep the paperwork with your property records, as it identifies the unit and its specification if anything needs to be checked or claimed later.
Replacement Glass near you
Choose your county or area for local details, towns we cover and the rules that apply where you live.
England
- Bedfordshire
- Berkshire
- Bristol
- Buckinghamshire
- Cambridgeshire
- Cheshire
- Cornwall
- County Durham
- Cumbria
- Derbyshire
- Devon
- Dorset
- East Riding of Yorkshire
- East Sussex
- Essex
- Gloucestershire
- Greater London
- Greater Manchester
- Hampshire
- Herefordshire
- Hertfordshire
- Isle of Wight
- Kent
- Lancashire
- Leicestershire
- Lincolnshire
- Merseyside
- Norfolk
- North Yorkshire
- Northamptonshire
- Northumberland
- Nottinghamshire
- Oxfordshire
- Rutland
- Shropshire
- Somerset
- South Yorkshire
- Staffordshire
- Suffolk
- Surrey
- Tyne and Wear
- Warwickshire
- West Midlands
- West Sussex
- West Yorkshire
- Wiltshire
- Worcestershire
Scotland
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