Replacement windows are new frames and sealed double- or triple-glazed units fitted into your existing openings after the old windows are taken out, improving warmth, security and noise reduction while meeting current building regulations.
We arrange replacement windows for homeowners in Derry/Londonderry and the wider County Londonderry. The job is planned, priced and managed by us and carried out by tradespeople engaged under our contract, so there is one agreement and one contact. On a typical home the work takes 1–2 days on site for a typical house, and guide pricing in Northern Ireland is £3,900–£7,700, VAT included.
- Guide price
- £3,900–£7,700 inc VAT
- Time on site
- 1–2 days on site for a typical house
- Postcodes
- BT48
- Planning rules
- Northern Ireland
- Local area
- Derry
- Survey
- Free, with a written quote
What should you budget for replacement windows in Derry/Londonderry?
Budgeting for replacement windows in Derry/Londonderry? The numbers below include VAT and are adjusted for Northern Ireland, where costs are about 14% below the national guide. The headline range is £3,900–£7,700. Nothing is final until we have measured up at a free survey and agreed the specification with you.
| Type of job | What it usually involves | Guide in Derry/Londonderry |
|---|---|---|
| One to three windows | Replacing a few problem windows, such as a bay or a rotten kitchen window, in uPVC. | £600–£2,600 |
| Whole house in uPVC | Eight to ten standard uPVC casement windows on a typical 3-bed semi, fitted and finished. | £3,900–£6,400 |
| Whole house in aluminium or flush sash | Premium frames, colours or period styles across a typical 3-bed home. | £6,400–£12,000 |
The main things that change the figure:
- Number and size of windows, including bays and large picture windows
- Frame material, colour and finish, inside and out
- Window style, such as sash, flush sash or tilt-and-turn
- Upper-floor access, scaffolding and the condition of reveals and sills
What does the job include in Derry/Londonderry?
- Made-to-measure frames in your chosen material, colour and style
- Double-glazed units as standard, with triple glazing as an option
- Careful removal and disposal of the old frames and glass
- Fixings, packers, foam and weather seals to suit your wall type
- Trickle vents, escape hinges and safety glass where regulations require
- Building regulations sign-off arranged and paperwork handed over
Local housing and replacement windows
Derry has Georgian and Victorian terraces around its walled city, alongside large post-war estates and newer developments. Coleraine, Limavady and Magherafelt mix older town centres with semis and estates, Portstewart has seaside villas, and rural areas have many detached homes and bungalows, often roughcast.
Terraces suit loft conversions and rear extensions, while rural bungalows commonly take extensions, loft rooms and driveways. Roughcast homes often need re-rendering, and coastal houses need roofline and window renewal.
None of this holds for every street in Derry/Londonderry, which is why we look at your actual house before pricing replacement windows rather than assuming from its age alone.
Planning and building rules in Derry/Londonderry
Which rules apply depends on where you live. For Derry/Londonderry, the answer is Northern Ireland, and the points below reflect that; we verify them with the council before quoting.
In Northern Ireland, like-for-like replacement windows and doors on a house rarely need planning permission. Listed buildings and conservation areas are the main exceptions, so check with the council before changing style or material.
The Building Regulations (Northern Ireland) apply to replacement windows, so the work needs building control approval or sign-off through an approved competent person route.
Rules change and every property is different, so we check the planning history and constraints for your address before we quote.
What happens after you get in touch?
Survey and measure
Book a visit and we'll come to you. The survey covers measurements, the state of what's there now and any obvious constraints, so the price that follows is based on your actual home, not an average.
Quote in writing
We turn the survey notes into a written quote. The price is fixed for the specification we agree, and the document sets out materials, scope and payment stages in plain language.
Plan and prepare
Next comes planning the work itself. We set a start date that suits you, line up the right trades, and make sure any approvals for replacement windows are in place before the first day on site.
Finish and handover
Work goes ahead as scheduled and you deal with one contact throughout. When the last trade leaves, we clear and clean the site, talk you through what has been done and pass on any certificates and care instructions.
How we work
Frequently asked questions
How much will replacement windows cost in Derry/Londonderry?
As a guide, expect to pay £3,900–£7,700 including VAT for replacement windows in Derry/Londonderry. That range is adjusted for Northern Ireland, which runs about 14% below the national guide. Where your project lands depends on size, materials, access and the condition of what is already there. We confirm a fixed price in writing after a free survey of your home.
How much do replacement windows cost?
Replacement windows for a typical 3-bed semi cost £3,900–£7,700, depending on the number of windows, frame material and glazing. A single standard uPVC casement usually works out at roughly £500–£950 fitted, while aluminium, flush sash and sliding sash styles cost more. Bays, large panes and upstairs access add to the price. We measure every opening during the survey and give you a fixed price for the agreed specification.
How do I look after new uPVC or aluminium windows?
Caring for new windows is simple: wash frames and glass with warm soapy water a few times a year, avoiding abrasive cleaners and solvents. Clear the drainage slots at the bottom of the frame so rainwater can escape, and put a drop of light oil on hinges and locking points once a year. Check seals and the sealant around the outside every few years, and replace any that have cracked or shrunk.
What happens at the survey?
We visit your home at a time that suits you, look at the area involved, take measurements and check access, condition and any services that might be affected. We talk through what you want from replacement windows, explain the options and answer questions. There is no charge and no obligation; afterwards we send a written quote.
What happens on the day the windows are fitted?
On fitting day we lay dust sheets, protect floors and furniture near each window, and then remove the old frame carefully to limit damage to plaster. The new frame is fixed, packed, sealed and glazed, and internal trims and external cills are finished. We take away the old windows and clean the glass before leaving. You only need to clear sills and take down curtains and blinds.
Nearby towns
Coverage for Derry/Londonderry spans BT48. Close by, Strabane, Limavady and Coleraine are covered too, and the rest of our UK-wide area follows the same survey-then-quote process from start to finish.

