Windows and doors cost in NI: 2026 price guide
What replacement windows and doors cost in NI (2026)
Three tiers cover almost every whole-house job. These are turnkey figures, supplied and fitted with old units removed, for a typical three-bed semi with eight to ten windows.
Source: 2026 quotes from NI window installers cross-checked against published NI pricing (Hurricane Windows Belfast, Smart Homes NI) and Republic of Ireland comparison anchors (Expert Windows, BuildPro) converted from euro. NI fitting rates run roughly 10 to 20 per cent below the GB mainland.
Cost per window and door
For a partial job, or to sanity-check a quote line by line, these are the NI 2026 supplied-and-fitted ranges per unit.
Source: NI installer quotes, June 2026. Ranges include removal of the old unit, fitting and basic making good, but not significant plaster or render repair, lintel work, or scaffolding for upper floors.
Cost of double glazing in Northern Ireland
Double glazing is the standard for replacement windows in NI: almost every uPVC, composite and aluminium window fitted today is an A-rated double-glazed unit, so the figures above are effectively your double glazing costs. In short, in Northern Ireland in 2026 you can expect to pay roughly £350 to £650 per standard double-glazed uPVC window supplied and fitted, rising to £650 to £1,200 for large or bay units.
For a whole house, double glazing a typical three-bed semi (eight to ten windows) runs about £3,000 to £6,000 in uPVC, or £6,000 to £10,000 for a mid-range job with A-rated glazing and a composite front door. Triple glazing adds cost for only marginal gains in most NI homes, so double glazing remains the value choice.
What drives the price
- Frame material. uPVC is the cheapest, aluminium the dearest (slimmer sightlines, around twice the price), with timber and timber-alternative in between. This is the single biggest lever.
- Glazing spec. A-rated double glazing is standard; triple glazing adds cost for marginal gains in most NI homes. Obscure, acoustic and toughened glass all add.
- Door choice. A composite front door costs roughly double a basic uPVC one, and bifold or patio doors are a tier above French doors.
- Size, style and quantity. Bay windows, sash styles and astragal bars cost more, and the more openings, the higher the total (though the per-unit rate often drops on a full-house order).
- Access and making good. Upper-floor windows may need scaffolding, and old or rendered openings can need lintel checks or plaster and render repair once the old frame is out.
Because new glazing improves energy efficiency, some lower-income NI households can get help with the cost through energy-upgrade funding. There is no standalone window replacement grant in NI, but windows can be funded as part of a wider package under the means-tested schemes. See our NI insulation grants guide for how window funding works, and the full home and energy grants guide to check whether you qualify before you pay for a full replacement.
Do you need FENSA in NI? No, and here is what you need instead
This is where Northern Ireland differs from every UK-wide guide. FENSA and Certass, the competent-person schemes installers use in England and Wales to self-certify window work, do not operate in NI. Replacement windows here are controlled work under NI Building Regulations, and approval comes from your local council Building Control, not from the installer ticking a self-certification box.
In practice that means the work should be notified to your council Building Control and meet the energy-efficiency standard, and you should keep the completion record, because a buyer’s solicitor will ask for evidence that replacement windows complied when you sell. We cover how this works in our NI Building Regulations guide. New windows also have to keep the required trickle ventilation, so do not let an installer block up vents to make a room feel less draughty.
Source: FENSA and Certass operate in England and Wales only; replacement windows in NI are approved through council Building Control under the Building Regulations (Northern Ireland) 2012, Technical Booklet F (conservation of fuel and power) and Technical Booklet K (ventilation).
The costs people forget
- Making good. Plaster repair inside and render or sealant outside once old frames are out, more on older or pebble-dashed homes.
- Lintels and structural checks. An opening with a failed or missing lintel needs fixing before the new window goes in.
- Scaffolding or access. Upper-floor and dormer windows can add a few hundred pounds for safe access.
- Disposal. Removing and tipping old frames and glass, sometimes itemised separately.
- VAT at 20 per cent. Replacement windows are standard-rated; always check whether a quote includes it.
How to get reliable quotes
Window quotes are notoriously hard to compare because each company prices its own product. A few rules make them useful.
- Get three written quotes against the same schedule. List every window by room, size and style so each installer is pricing the same job.
- Be wary of high-pressure discounts. A price that is only valid if you sign today is a sales tactic, not a fair quote.
- Confirm Building Control. Ask how the installer handles the council Building Control notification, since there is no FENSA route in NI.
- Check the guarantee. Get the frame and glazing guarantee and any insurance-backed warranty in writing.
Frequently asked questions
Conor writes the NI building and renovation cost benchmark guides for NI Trades. He draws on a civil-engineering background and on quotes from working FMB, OFTEC and NICEIC tradespeople across Northern Ireland to keep the price ranges realistic. He holds a BEng (Hons) in Civil Engineering from Queen’s University Belfast.