In this article we cover:
- How much a better BER could add to your home’s value
- What the research says about retrofit costs and returns
- Why location and property type make a difference
- What the findings mean for home improvers and those building new
- How the new BER scale works
- What grants and green mortgage options are available
A new report from the Sustainable Energy Authority of Ireland (SEAI) has looked at how a home’s Building Energy Rating (BER) is linked to its sale price.
The research shows buyers do appear to be willing to pay more for homes with better energy ratings. How much more depends on the property, where it is and the rating it achieves.
The SEAI hopes its research will encourage homeowners to invest in energy efficiency measures.
What does the research say?
The SEAI report, Building Energy Ratings and Property Sales Prices in Ireland, looked at 49,350 homes sold across Ireland in 2023 and 2024.
The researchers used actual sale prices rather than just asking prices and also took account other things that affect a property’s value, including its location, size and age.
Nationally, homes tended to sell for an average of 2.7 per cent more for every step up the old 15-point BER scale.
That might not sound like a huge amount, but it can add up. On a €400,000 property, 2.7 per cent is €10,800. And the difference was even bigger in rural areas, where homes tended to sell for an average of 4.7 per cent more for every step up the scale.
That doesn’t mean spending a few thousand euro to improve your BER by one grade will automatically add €10,800 to your home’s value. The figure is an average across thousands of sales, and every property is different.
The report also found that the difference was smaller when looking at asking prices – 2.3 per cent compared with 2.7 per cent for actual sale prices. So, while a better BER might not make a huge difference to the price a house is advertised at, buyers may be willing to pay more for it when it comes to making an offer.
What could that mean for your own home?
The SEAI report includes comparisons between individual BER grades. For example, on the old scale, it found that moving from D2 to B2 could lead to a sale-price increase of around 13 per cent. Moving from D2 to an A rating saw an increase of around 19 per cent.
For example, if your home is worth €400,000 and has a D2 rating, the research suggests that a similar home with an A rating could be worth around €76,000 more.
But it doesn’t prove that spending a particular amount on a retrofit will produce a particular increase in value. The finished house, the quality of the work and the local property market will all make a difference.
Where you live matters
The research found that the percentage increase linked to a better BER was higher in rural areas than in Dublin.
| Property category | Average increase associated with each step on the old BER scale |
| National average | 2.7 per cent |
| Rural homes | 4.7 per cent |
| Urban homes | 2.2 per cent |
| Urban homes outside Dublin | 2.7 per cent |
| Urban Dublin | 1.8 per cent |
| Houses | 2.8 per cent |
| Apartments | 2.2 per cent |
Source: SEAI, Building Energy Ratings and Property Sales Prices in Ireland, August 2026. These are averages rather than predictions for individual homes.
While a rural home may see a bigger percentage difference, it doesn’t necessarily mean the owner will make more money from a retrofit. A larger house may cost more to upgrade, and a smaller percentage increase on an expensive Dublin property can still amount to a huge financial leap.
Can a retrofit pay for itself?
The SEAI researchers didn’t just look at sale prices, they also compared the value linked with better BERs against the cost of carrying out energy upgrades through SEAI’s One Stop Shop scheme.
The costs used in the study came from SEAI’s National Retrofit Quarterly Report for the first quarter of 2025. They are historical median figures, so they shouldn’t be treated as current quotations, but they give an idea of the scale of investment involved.
| Type of home | Median total upgrade cost | Median cost to homeowner after grants | Typical BER improvement in the cost data |
| Apartment | €22,915 | €16,378 | D2 to B1 |
| Terraced house | €51,156 | €34,962 | E2 to A2 |
| Semi-detached house | €61,584 | €38,500 | D2 to A2 |
| Detached house | €66,149 | €42,467 | D2 to A2 |
Source: SEAI report, Table 2. The figures are separately reported medians and are intended as a guide, not an itemised budget for a particular project.
The figures suggest that, in many cases, homeowners could get back more in added property value than they spend on the energy upgrade after grants.
There is a bit of a catch, though. Energy upgrades are often done as part of a bigger renovation. You might insulate the house, replace the heating system and fit new windows, but also put in a new kitchen, replace the floors or change the layout. It’s difficult to say exactly how much of the increase in value comes from the energy work and how much comes from everything else.
So, the report isn’t saying that every retrofit will pay for itself. What it does show is that improving your BER can be money well spent, particularly if you’re already planning to renovate.
What do the building regulations require?
Energy upgrades aren’t always optional when you’re carrying out major renovation work.
Under Part L of the Building Regulations, major renovation requirements can apply when more than 25 per cent of the building envelope is affected by the work. The building envelope includes elements such as the walls, roof, floors and windows.
Where the requirements apply, the building must be upgraded to the cost-optimal level as far as technically, functionally and economically feasible. The guidance includes different ways of demonstrating compliance, depending on the work being carried out.
What about new builds?
If you’re building a new home, energy efficiency is already a major part of the design process.
New homes in Ireland must meet Nearly Zero Energy Building (NZEB) requirements under Part L. These set standards for energy performance, carbon emissions and renewable energy. Compliance is assessed using the Dwelling Energy Assessment Procedure, known as DEAP.
The SEAI research should give self-builders some reassurance that the money spent on creating an energy-efficient home isn’t simply a cost of meeting regulations. Buyers seem to place a value on better energy performance, so it can also be part of the long-term value of the finished house.
However, the report doesn’t calculate how much extra it costs to build a new home to NZEB standards compared with a less efficient one.
The BER scale has changed
One thing to bear in mind when you’re reading the research is that the homes in the study were sold in 2023 and 2024, before Ireland introduced its new BER scale.
The old system had 15 grades, running from A1 down to G. Since May 2026, newly issued BER certificates use a simpler eight-category scale: A0, A, B, C, D, E, F and G.
A0 is the new top category for highly energy-efficient buildings that do not use fossil fuels. A-rated homes are among the most energy efficient, while G-rated homes generally need much more energy to heat.
The new certificate also gives more information about the property’s energy use, emissions and renewable energy contribution. It includes a QR code linking to further BER information and upgrade advice.
Existing BER certificates remain valid for 10 years from their date of issue, so you don’t need to get a new one simply because the scale has changed.
The important point is that the SEAI research uses the old grades. A move from D2 to B2 in the report is not the same as moving two steps on the new scale.
How much help can you get?
Grants can make a big difference to the overall cost of a retrofit, and they are an important part of the SEAI report’s investment calculations.
For existing homes, there are two main approaches. You can apply for individual grants and arrange eligible improvements yourself, or use the One Stop Shop scheme for a more comprehensive, managed upgrade.
The One Stop Shop route can be useful if you are planning several measures together, such as insulation, windows, heating and ventilation. The provider manages the process and deducts the grant from the cost upfront.
Individual grants may suit homeowners who want to carry out work in stages or who are already planning a renovation and want to include specific energy improvements.
SEAI currently provides support for measures including attic and wall insulation, windows and doors, heat pumps and solar PV. Grant amounts and eligibility conditions vary, and they can change, so it is worth checking the current figures before putting together your budget.
If you are extending and renovating at the same time, don’t assume that all of the work will qualify for grant support.
Grants are generally intended to improve existing homes, not to pay for the construction of a new home or a new extension. For example, SEAI’s windows and doors grant has specific conditions relating to the age of the property and the parts of the building being upgraded.
What if you own an older house?
If you own an older stone, brick or traditionally constructed house you need to take particular care with retrofit work.
SEAI’s Traditional Homes Pilot provides a route for eligible traditionally constructed homes, generally dating from before the 1940s, to access supported upgrades through specialist providers.
Unlike the standard One Stop Shop scheme, the pilot doesn’t need the home to achieve a post-works BER of B or better. The aim is to carry out improvements that are appropriate for the building and its heritage value.
Could a better BER help with your mortgage?
A better BER may also make a difference when it comes to borrowing.
Several lenders offer green mortgage products with lower interest rates for eligible energy-efficient homes. The exact requirements vary, but homes rated B or better are often eligible for particular products.
There is also the government-backed Home Energy Upgrade Loan Scheme, which provides unsecured loans for qualifying energy upgrades. The scheme allows some of the borrowing to be used for other home improvements, provided the required proportion is spent on eligible energy work.
This may be useful if you are combining a retrofit with a wider renovation, but it is still borrowing, so the repayments need to be affordable and the full cost should be considered.
