A Building Energy Rating (BER) is your home’s energy label — like the sticker on a fridge, but for a house. It matters when you sell or rent, it’s often required before claiming grants, and it’s the clearest measure of whether your upgrades are working. This guide explains the scale, the cost, the legal rules, and how to move up it.
What the BER scale means
The rating is based on the building’s energy performance — insulation, heating system, windows, ventilation — not on your personal habits. It’s expressed as kWh per m² per year and mapped to a band. Since 24 May 2026 new certificates use a simplified scale without sub-bands:
- A0 — a new top band for very efficient, zero-emission homes
- A (formerly A1–A3) — very efficient (new or deeply retrofitted homes)
- B (formerly B1–B3) — efficient; the target for most retrofits
- C / D — typical of many older Irish homes
- E / F / G — poor; high bills and priority for upgrades
Certificates issued before that date keep their A1–G rating and remain valid for 10 years. Both scales, with the figures behind each band, are in what is a good BER rating?
What a BER assessment costs
A BER is carried out by an SEAI-registered BER assessor who visits your home, records its construction and systems, and lodges the certificate. Expect to pay €150–€350 depending on the property size, location and assessor. See our BER assessment cost guide for what affects the price and how to prepare.
When you legally need a BER
You must have a valid BER when you:
- Sell a home — the rating must be shown in the advertisement.
- Rent a home — same requirement for the listing.
- Complete a new build.
It’s also required after most SEAI grant works, so your improved rating is recorded.
How to improve your BER
The rating responds to the same upgrades that cut your bills — so improving your BER and saving money go hand in hand:
- Insulation — attic and walls deliver the biggest, cheapest gains. See insulation.
- Heating — a heat pump can lift the rating significantly in a well-insulated home.
- Heating controls — zoning and timers help.
- Solar PV — on-site generation improves the rating and cuts bills. See solar panels.
Most of these are part-funded by SEAI grants. We map out a practical path in how to improve your BER rating.
Why BER affects your home’s value
A better BER means lower running costs, and buyers and renters increasingly notice. A higher-rated home is cheaper to live in, easier to sell or let, and better placed for future rules on minimum energy standards.