SEAI started paying a grant for replacement windows and external doors in March 2026. It is worth up to €5,600 on a detached house. Most people who apply for it will be told no, and the reason is almost always the same one.
| Upgrade | Apartment | Mid-terrace | Semi-D / end | Detached |
|---|---|---|---|---|
| Windows, complete upgrade | €1,500 | €1,800 | €3,000 | €4,000 |
| External doors | €800 per door, maximum 2 | €800 per door, maximum 2 | €800 per door, maximum 2 | €800 per door, maximum 2 |
SEAI fixed amounts, current at 27 August 2026. Windows and doors can be claimed together, so €5,600 is the most a detached house can get.
The grant is a fixed sum set by your house type. A detached house gets €4,000 for windows whether the job costs €12,000 or €30,000. External doors are €800 each and you can claim for two, so the ceiling is €5,600.
Before you get excited about that number, read this next line twice. You cannot have the windows grant unless your attic and your walls are already insulated to a standard SEAI calls good. Not adequate. Not partly done. Good.
This is not a technicality buried in the small print. It is the first thing SEAI checks and it is the reason most refusals happen. If your walls are uninsulated or half insulated, the windows grant is not available to you yet, no matter how bad your windows are.
The wording is specific. Your post works BER advisory report has to note the attic and the walls as Good or Very Good. Those are the two ratings that pass. Fair does not pass. Poor does not pass.
SEAI also names a Heat Loss Indicator threshold of 2.3 W/K·m2 or lower on the same page. Ask your BER assessor which of these applies to your house before you commit to anything, because the two conditions do not always land the same way on the same building.
There are three ways to find out where you stand. If you already took an SEAI grant for attic or wall insulation, SEAI says you are fine. If you have a BER cert, the advisory report that came with it rates your attic and walls in plain words. If you have neither, or your cert is old, pay a BER assessor to look before you order windows.
A homeowner in Wicklow went through Warmer Homes and got a free external wall wrap. His rating moved from E to D. He says the house did not feel noticeably warmer afterwards.
When the windows grant opened he applied. He was refused. The wall measure he had already received scored fair on his report rather than good, so he did not clear the bar, and because the walls had already been done externally he had no route to a second wall grant either.
That is the trap in one story. Having had work done is not the same as having passed. Read the words on your own advisory report before you assume you qualify.
The new windows have to reach a U value of 1.4 W/m2K or lower. Lower is better, so 1.3 passes and 1.5 does not. Plenty of ordinary double glazing sold in Ireland sits above 1.4, so do not assume the cheapest quote clears it.
Get the U value in writing on the quote, per window, before you sign. A supplier who will not put it on paper is a supplier who will cost you the grant.
It is a complete windows upgrade, not a partial one. You are replacing existing single or double glazed windows across the home, and the doors you claim for have to be inefficient ones you are replacing.
Get grant approval before anyone lifts a tool. SEAI is explicit that approval must be in place before works start, and a job already underway cannot be rescued by applying afterwards. This is the single most common way people lose a grant they were entitled to.
The sequence is quotes from registered contractors, then apply, then wait for the written offer, then works, then the post works BER, then the claim. You have 30 days to accept the offer once it arrives and eight months from the date of the offer to finish and claim.
There is a €50 BER grant toward the post works assessment. It does not cover the full cost of a BER, so budget the difference.
If your walls or attic need doing first, do them first, claim those grants, and come back for the windows. Look at attic insulation, cavity wall, internal wall and external wall insulation first.
The home has to have been built and occupied before 2011, and it needs its own MPRN. Homeowners and private landlords are both listed as eligible applicant types.
You have to use an SEAI registered contractor, or go through a One Stop Shop. Your own builder, your cousin, or a very good local joiner does not qualify no matter how good the work is. Check the register before you take a quote seriously, on our list of registered installers.
If your grant payments cross €10,000 in a single calendar year you will need tax clearance. That is easy to arrange and easy to forget about until it holds up your payment.
SEAI does not publish an expected cost for a windows job, so we are not going to invent one. What we can tell you is that on a typical three bed semi, quotes for a full window replacement in triple glazed uPVC generally run into five figures, and the grant covers a slice of it rather than most of it.
Get three quotes and get them itemised per window. If a price moves upward after you mention the SEAI grant, that is your answer about that supplier, and you should go to the next one. Real figures from Irish households are on what homeowners actually paid.
Windows are one of the worst value measures per euro of heat saved, which is exactly why SEAI puts insulation ahead of them. If the money is limited and the attic is bare, the attic wins.
It can happen, and it is worth understanding before you spend. Old draughty windows ventilate a house by accident. Replace them with well sealed units and that accidental ventilation stops.
If the house has no deliberate ventilation to take over, moisture that used to leak away now sits in the room and lands on the coldest surface it can find. That tends to be a wall behind a wardrobe or a corner in a north facing bedroom, and the result is condensation and mould in places that were dry last winter.
SEAI requires adequate ventilation as a payment condition for exactly this reason. Make sure your installer is fitting the vents specified rather than treating them as optional, and keep them open.
One. Check your BER advisory report, or get an assessor to look, and confirm your attic and walls read Good or Very Good.
Two. Take quotes from SEAI registered contractors with the U value of each window stated in writing.
Three. Apply to SEAI and wait for the written offer. Accept within 30 days.
Four. Have the work done, get the post works BER, then submit the claim. Payment comes by bank transfer. Add the whole job up first on the grant calculator.
Check your insulation rating first, then take three quotes with the U value stated in writing on each one.
€1,500 for an apartment, €1,800 mid terrace, €3,000 semi detached or end of terrace and €4,000 detached, for a complete windows upgrade. External doors are €800 each up to two doors, so a detached house can claim €5,600 in total.
Almost always because your attic and wall insulation are not rated Good or Very Good on your BER advisory report. Fair is not enough. The other common reasons are a house built or occupied after 2010, windows that do not reach a U value of 1.4 or lower, or starting the work before the grant offer arrived.
Only if the completed wall measure is rated Good or Very Good on your report. Having had wall insulation done is not the same as passing. A wall that came out fair will still block the windows grant, and if the walls were done externally there is no second wall grant available to fix it.
Yes. SEAI pays for a complete windows upgrade, replacing existing single or double glazed windows across the home, not a few of the worst ones. Doors are separate and capped at two.
1.4 W/m2K or lower. Lower numbers are better, so 1.3 passes and 1.5 does not. Ask for the U value in writing on the quote for each window, because a lot of standard double glazing sold here does not reach it.
Yes. SEAI lists properties owned by landlords among the eligible applicant types, provided the property was built and occupied before 2011 and the insulation condition is met.
No. The work has to be done by an SEAI registered contractor or through a registered One Stop Shop. Work you do yourself, or work by an unregistered fitter, cannot be grant aided afterwards.
You have 30 days to accept the grant offer and eight months from the date of the offer to complete the works and claim. Nothing can start before the offer is in your hands.
Checked against the official pages on 27 August 2026. Grant terms change, so confirm current amounts with SEAI or your installer before you commit.