About the data

Why I made this

I went looking for what a heat pump would actually cost me, in my own house, and could not find it. SEAI publishes the grant. Installers quote the job. The gap between those two numbers — the bit you actually pay, and how long it takes to come back on the bills — nobody publishes. So I worked it out from the file SEAI already puts online: every home energy rating ever issued in Ireland, 1,077,114 of them after the obvious junk is dropped.

I am not selling anything, and there is no lead fee in the request form yet — if that ever changes it will say so on the form itself, before you fill it in.

Photo
to come

Four files, all public

Everything on this site is built from four files that anyone can download.

What	Who publishes it	Edition we used
Every home energy rating ever issued	SEAI, BER Research Tool	file of 8 September 2026
Middle price paid for each upgrade	SEAI, median costs of upgrades	2025
Middle price of a full upgrade through a One Stop Shop	SEAI	2025
What each fuel costs per unit of heat	SEAI, fuel cost comparison	1 July 2026

Grant amounts come from SEAI's own grant pages and were last checked on 2026-09-07. The date at the foot of every page is the date this site was last rebuilt from those files.

BER file 2026-09-08: 1,441,089 rows; 1,077,114 after filtering to existing dwellings with a valid rating and 35–400 m² floor area; 601,544 assessed 2019 or later. Upgrade costs: n = 47,067 upgrades. One Stop Shop costs: n = 1,406 homes.

The rating scale changed on 24 May 2026

Every rating on this site is shown on the eight-grade scale: A0, A, B, C, D, E, F, G. That scale came into force on 24 May 2026 under S.I. No. 168 of 2026, which transposes the EU Energy Performance of Buildings Directive. The regulations put it plainly — the scale is "simplified to use only letters and the previous subdivisions shall no longer apply". A0 is a new top grade, for homes that use very little energy and burn no fossil fuel.

Nothing about the certificates people already hold changed. A certificate issued before that date stays valid for ten years and is still accepted for selling or renting. It just shows an older, longer scale.

So we fold the old ratings into the new letters. The rating file we build on runs back to 2009 and every record in it predates the change, so a home on file as a B2 is shown here as a B, a C1 as a C, and so on.

For A, B and C that fold is exact. For D down to F it is not, and we say so on the page. The new scale kept the A, B and C boundaries but moved the ones below them. A home whose certificate says D2 can be a D or an E today; most homes on file as an F would be shown a G. Every rating page carries the figure for its own group in the small print, so you can see how much it applies to you. Where it matters, trust the number of units, not the old letter.

Target: a B, i.e. ≤ 150 kWh/m²/yr; the stricter figure the One Stop Shop requirement used to be written as is ≤ 125. Band edges on the current scale, read from SEAI's own sample certificate for it (seai.ie/ber/new-simplified-scale, read 8 September 2026): A0 ≤ 42 and no fossil fuels, A ≤ 75, B ≤ 150, C ≤ 225, D ≤ 275, E ≤ 325, F ≤ 375, G > 375 kWh/m²/yr. Fold applied to the file: A1–A3 → A, B1–B3 → B, C1–C3 → C, D1–D2 → D, E1–E2 → E, F → F, G → G. The A, B and C edges are exact — 75, 150 and 225 were also the old A3, B3 and C3 edges. D to G are not: the new scale re-cut them at 275 / 325 / 375 where the old scale cut at 260 / 300 / 340 / 380 / 450. Measured over all 1,077,114 records we use, folding the letter agrees with re-cutting the record's own kWh/m²/yr for 84.5% of homes: 100% of A, B, C and G, but 71.7% of D (28.3% read as E today), 35.2% of E (59.0% F, 5.8% G) and 3.7% of F (96.3% read as G). Each rating page publishes the figure for its own group as `recut_agreement`, and `provenance.json` carries the full table. No pre-2026 record can fold into A0, because the old scale never recorded the fossil-fuel test.

The grant target moved with the labels, not the physics. SEAI: "The requirement to reach a post-works BER of B2 under the One Stop Shop Scheme or Community Energy Grant will now become a requirement to reach a B post-works BER. The minimum required improvement in energy efficiency remains the same." So the target we work to is a B. Where it is useful we also show, in the small print, what the stricter old target would cost.

The licence

The rating file is Irish public sector information. We are required to say so, and we do, at the foot of every page:

Contains Irish Public Sector Data licensed under a Creative Commons Attribution 4.0 International (CC BY 4.0) licence

We are not SEAI, and SEAI has not checked or endorsed anything here.

What the rating file cannot tell us

Homes appear more than once. The file has no house identifier. A home rated in 2016 and again after an upgrade in 2024 is two rows, and we cannot tell that they are the same house. So the counts on this site are counts of ratings, not of homes.

Rated homes are not typical homes. A rating is usually only done when a house is sold, rented or upgraded. Homes that have stayed in the same family for forty years are badly under-represented — and those are exactly the homes that most need the work. Expect the real housing stock to be a little colder and older than the file suggests.

A rating is a survey, not a laboratory test. Assessors record what they can see and measure on the day. Where they cannot see, standard default values are used, and those defaults tend to be pessimistic about old construction.

Prices are last year's. The upgrade costs are the middle price paid across the country in 2025. Prices vary by county, by access, by how busy installers are, and by what they find when they open up a wall.

How to get the same files yourself

The rating file is a free download from SEAI's BER Research Tool — no registration, one large zip. Fuel prices and median upgrade costs are published by SEAI as PDFs. Every URL is listed at the foot of this page.

data.gov.ie lists the BER Research Tool under a Creative Commons Attribution 4.0 licence. SEAI's own terms and conditions document for the same file uses narrower wording about personal, research and education use. We have written to SEAI asking them to confirm which applies to a site like this one, and we will publish their answer here. If they tell us the narrower wording governs, the aggregate figures come down.

We keep a record of exactly which version of each input produced the figures on the site, including a checksum of every input file, so any number here can be traced back to the file it came from.