Home energy guide
Window replacement cost and grant in Ireland
A homeowner guide to indicative replacement-window costs, potential grant support and the details that affect installation.
Last reviewed: September 2026
Indicative costs
HomePlanIQ uses current irish replacement-window market pricing for this guide, covering 2026 planning range. Where a stored median is available, the displayed range applies the existing HomePlanIQ planning spread. These figures are planning information, not quotations or guarantees.
Reference range is normalised around a typical 10-window replacement project. Number of windows, dimensions, glazing, frame material and large openings can materially affect the quotation.
Current SEAI grant position
Replacement windows can be a potential Individual Grant measure for qualifying homes. Stored amounts are up to €4,000 for a detached house, €3,000 for a semi-detached home, €1,800 for a terraced home and €1,500 for an apartment.
The existing windows, completed-home fabric and other eligibility requirements matter. Unknown or triple-glazed existing windows do not establish potential support in the current calculator. Check the official SEAI windows and doors information.
What affects replacement cost?
The number and size of openings, frame material, glazing specification, opening style, access and making-good work all affect the price. Double and triple glazing are different specifications, and the right choice depends on the design, existing walls and the performance required.
Installation may involve reveals, sills, lintels, trims, plaster, external finishes and disposal of old frames. Ventilation should also be considered when improving airtightness, particularly where existing background ventilation is changed.
Windows and other upgrades
Window work can interact with external or internal wall insulation because the junctions and reveals need to be coordinated. It can also be sensible to plan window replacement alongside other fabric upgrades, rather than treating each detail in isolation.
Use the upgrade guides hub to compare windows with wall insulation and other home improvements.
Plan this upgrade with the rest of your project
Use the HomePlanIQ calculator to estimate this work alongside other home improvements. It provides indicative project ranges and potential grant information, not an exact contractor quotation.
Open the HomePlanIQ calculatorSources and methodology
Cost figures use the existing HomePlanIQ source record for Windows, checked on 2026-09-09. Grant information uses the existing SEAI - Windows and doors grant record, checked on 2026-09-09. Confirm current rules and application requirements with the official SEAI source.
For more detail on HomePlanIQ cost ranges and potential grants, read the Methodology & data sources page or browse all upgrade guides.