Double glazing upgrade, Glasgow
Double glazed sash windows in Glasgow.
Keep your original sash and case windows and make them warm and quiet. We leave the case in the wall and make new slimline double glazed sashes for it in our own workshop in Glasgow's East End, matched to the original sections, mouldings and astragals.
How it works
New sashes, original case
The case, the architraves and the shutters stay exactly where they are. Only the sashes are new, so there is no disturbing of the stonework and far less upheaval than a full replacement.
1. Survey
A free survey of every window. We tell you which ones suit a double glazing upgrade, which are better restored, and what consent, if any, the building needs.
2. Made in Glasgow
New timber sashes are made in our workshop on Strathclyde Street with slimline double glazed units, to the pattern of your originals.
3. Fitted properly
Hung on new cords with rebalanced weights, with Aquamac draught proofing, brass or chrome fittings and simplex hinges for safe cleaning from inside.
4. Finished
Traditional pointing and full decoration inside and out are included as standard, and the new sashes carry a 10 year guarantee.
The rules in Glasgow
Double glazing a listed or conservation area home in Glasgow
Many of Glasgow's tenements and terraces are listed or sit in a conservation area, so it is worth knowing where you stand before you start.
- Repairs need no permission. Glasgow City Council says repairs to original windows using the original materials do not need planning permission or listed building consent.
- Listed buildings: fitting new double glazed sashes changes the glazing, so it needs listed building consent. Replacing a whole window needs listed building consent and planning permission.
- Conservation areas (not listed): rear windows, and side windows that do not face a road, can be changed without planning permission. At the front, no permission is needed if the new window is the same or substantially the same, meaning the same way of opening, the same number and arrangement of panes, and the same frame and astragal sizes and colour. Otherwise you apply for prior approval.
- uPVC is not acceptable in listed buildings in Glasgow, so we will recommend timber.
Keeping the original case and matching the sashes to it is usually the easiest case to make to the council. We help with the application, drawings included. The full detail, with the council's own wording and links, is in our guide to listed buildings and double glazing.
Why upgrade rather than replace
Warmth without losing the window
- Original case, architraves and shutters stay in place
- New sashes matched to the original sight lines and astragals
- Draught proofing, new cords and full decoration included
- Upgrade the street facing rooms and simply restore the rest, room by room if you prefer
- A 10 year guarantee on the new sashes
Replacing single glazing with double glazing may qualify for an interest free Home Energy Scotland loan, and you must have its written offer before work starts. See funding for sash windows.
★★★★★
“I live in an A listed Alexander Greek Thomson flat and my sash windows had strict regulations to follow. Listed Window Refurbishment took everything into consideration and did an incredibly professional job. Their craftsmanship is outstanding and the team were a pleasure to work with.”
Our Glasgow work
From tenement flats to Scotland Street School
Every window we make passes through our own workshop in Glasgow's East End. Our work in the city includes Scotland Street School Museum, Royal Exchange Square, the Fairfield Shipping Offices in Govan, The High School of Glasgow and Castlemilk Hall in Carmunnock, alongside flats and villas from the West End to the Southside.
Common questions
Double glazed sash windows in Glasgow
Can I have double glazed sashes in a listed building in Glasgow?
Often, yes, with listed building consent. New sashes in the existing case keep the original window and its appearance, which is what the council looks for. We help with the application, drawings included.
Will the windows look different?
The new sashes are made to the original profiles, mouldings and astragal patterns, and the units are slimline, so the glazing lines match what was there before. From the street, the window reads as it always has.
Can you double glaze just some of the windows?
Yes. Every window is surveyed and quoted individually, so you can upgrade the street facing rooms and simply restore the rest.
What about windows that cannot be saved?
Where a case is beyond repair, we make a complete new timber sash and case window to match, single or double glazed. See new sash windows.
Warm rooms, original windows. Let us have a look.
A free survey of every window, and a written, itemised quotation.
Arrange a free survey
Not sure whether to restore, upgrade or renew? Let us have a look.
Tell us a little about your windows, with a photo or two if you have them, and we will call you back to arrange a visit.
You enquire
Send the form, with photos if you have them, or phone us. We aim to call you back the same working day.
Free survey
We visit at a time that suits you and assess every window individually.
Written quote
A clear, itemised quotation with no hidden extras — and never any obligation.