BER Ratings in Ireland: A Homeowner's Guide
A clear explanation of what a BER rating means, how Ireland's new A0–G scale works, and how you can improve your home's rating.
What Is a BER Rating?
A Building Energy Rating (BER) shows the energy performance of a home. It is based on the home's construction, insulation, windows, heating, hot water, ventilation and lighting, and is calculated using SEAI's official DEAP software.
The rating reflects the energy needed for heating, hot water, ventilation and lighting under standard occupancy, so homes can be compared fairly. Every BER certificate comes with an advisory report suggesting ways to improve the home's energy performance.
The New A0–G Scale
From 24 May 2026, Ireland uses a simplified scale of eight categories: A0, A, B, C, D, E, F and G. Sub-categories such as A1, B2 or C3 no longer apply to new certificates. A0 is a new category for the most efficient homes that do not use fossil fuels.
Source: SEAI — New Simplified BER Scale
- A0Highest performing — no fossil fuels
- A
- B
- C
- D
- E
- F
- GLeast efficient
Certificates issued under the previous scale (A1–G, including A2, B1, C3 etc.) remain valid until they expire. See SEAI's guide to the new scale.
What Different BER Ratings Indicate
A new top category for very energy-efficient, zero-emission homes that use no fossil fuels on site. A home must meet several strict conditions to reach A0.
Very good energy performance. Typically well-insulated homes, often with efficient, low-carbon heating such as a heat pump.
Average performance, common in Irish homes. There is usually room for improvement in insulation, heating or controls.
Poor energy performance. These homes are likely to need more energy to stay warm and often have the most scope for upgrades.
Why Your BER Rating Matters
Selling
A valid BER is legally required when a home is offered for sale, and the rating must be included in property advertisements.
Renting
Landlords need a valid BER when a property is offered for rent, including when a tenancy is renewed.
Upgrading
A BER and its advisory report show where energy is lost and can help you plan improvements. A BER is also commonly required for certain SEAI grant-supported upgrades.
Factors That Influence Your Rating
- Size, shape and orientation of the home
- Walls, roof and floor construction and insulation
- Windows and doors, including glazing type
- Heating system, fuel type and efficiency
- Heating controls and hot water system
- Ventilation and air tightness
- Lighting
- Renewable energy, such as solar panels or a heat pump
Documentation for insulation, heating and other upgrades helps the assessment reflect your home accurately. See Preparing for Your BER.
How to Improve Your BER Rating
These are common upgrades that may improve a rating. The effect varies from home to home, so no specific result can be promised.
Attic insulation
Often one of the simpler upgrades for homes with little or no attic insulation.
Wall insulation
Cavity, internal (dry-lining) or external insulation, depending on how the walls are built.
Heating upgrades
A more efficient heating system, or a heat pump where the home is suitable.
Heating controls
Zoned heating, thermostats and timers help the system run more efficiently.
Windows and doors
Replacing older single or poorly performing double glazing and draughty doors.
Solar panels
Solar PV or solar water heating can add a renewable contribution to the rating.
Low-energy lighting
Switching to LED lighting throughout the home.
Grants for many of these upgrades are available from SEAI.
BER Rating Questions
Want to know your home's rating? Michael carries out every assessment himself.
Need a BER Assessment for Your Property?
Request a quotation online or speak to Michael directly about your property.