1. What exactly happened to the scale
Two changes at once, and the second is the one noticed less often. The scale and the methodology changed together.
| What changed | Content |
|---|---|
| Range of the scale | the former A to H was replaced by A to G |
| Limit values | the energy performance values matching the classes were redefined with it |
Class A still denotes the best performance, but the worst is now G rather than the former H. There is therefore not merely one class fewer: the whole distribution has been redefined.
2. What happens to existing certificates
The answer is clear and reassuring, but it has a long tail. Existing certificates remain valid.
According to information published by the Ministry of Climate, the change does not affect currently valid energy certificates or their validity: a certificate issued under the old scale remains valid until it expires, and a new certificate is prepared under the new scale. The new scale applies to new certificates.
During the transition, therefore, certificates issued under both scales are in circulation, and they cannot be compared directly. The ten-year validity of KEK certificates means old-scale certificates will be on the market for years.
3. Why classes cannot be compared over time
Three reasons, and they compound. The boundaries of the scale differ, the limit values differ, and the calculation methodology has changed, which affects the figure itself. Comparing the classes of two certificates issued at different times therefore says nothing about which building is more efficient.
The only comparable quantity is the energy performance value together with the date it was issued, and even that requires knowing the methodology. The practical rule is short: always look at the date of a certificate before interpreting its class.
4. What it means for a sale
Three consequences on the property market, and the third can cut both ways. They concern comparability and price.
| Situation | Consequence |
|---|---|
| An advertisement shows a class without a date | the letter says nothing if the scale is unknown |
| Comparing buildings with old and new certificates | requires looking at the dates |
| Commissioning a new certificate | may yield a different class, without the building having changed |
The professional recommendation follows directly: where a building has a valid old certificate, replacing it is not automatically beneficial, and it is worth weighing before commissioning. A new one is made when it expires.
5. Why comparability was the point
One observation explains the whole exercise, and also why Estonia changed less than others. The scales were harmonised at European level.
According to information published by the Ministry of Climate, several countries had accumulated whole strings of plus and minus signs on the letter denoting the class, which impeded comparability of energy performance between buildings. Estonia's scale was already simple, so the change affects Estonia less than some other countries.
The benefit arises above all in cross-border comparison, which matters to international investors and buyers. In local comparison the benefit is smaller.
Summary and four practical rules
The A to H scale was replaced by A to G, and with it the whole class distribution and the matching limit values were redefined. Existing certificates remain valid until they expire, so certificates issued under two different scales will be on the market for years, particularly the ten-year KEK certificates. Classes cannot be compared over time, because the scale boundaries, the limit values and the calculation methodology all differ.
Four rules: look at the date of a certificate before interpreting its class. Do not compare classes from certificates issued at different times directly. Explain to a seller that a new certificate may yield a different class without the building having changed. Do not replace a valid old certificate without a reason.
This article offers professional orientation as at the date of verification. It replaces neither the regulations in force nor the assessment of a competent specialist.