1. What changed on 1 June 2025
Four things at once, and their combined effect is greater than any one of them. They entered into force on the same date.
| What changed | Content |
|---|---|
| Class scale | the former A to H was replaced by A to G |
| Limit values | the energy performance values matching the classes changed with the scale |
| Scope | the five-year transition of houses from low-energy to nearly zero-energy construction was deemed complete |
| Regulations | three were amended: minimum requirements, calculation methodology, and requirements for the certificate |
One clarification forestalls unnecessary worry: existing energy certificates and their validity are unaffected. An old certificate remains valid until its expiry; only reading it now requires knowing its date.
2. Why the scale was replaced
The reason is not domestic, and it explains why the change came when it did. Its basis lies in a European directive.
According to information published by the Ministry of Climate, the energy certificate scale is being updated across the European Union. Unlike Estonia, 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.
Under the new scale, A denotes the best and G the worst energy performance. The aim is therefore comparability between countries rather than a tightening of Estonian requirements as such; the tightening follows a separate logic, that of cost-optimal level calculations.
3. What the update brought to the calculation
The methodology changed together with the scale, and the reason is measurable. The old methodology did not reflect actual use.
According to information published by the Ministry of Climate, years of practice have revealed components of building energy consumption that have changed or were not previously accounted for. The methodology was corrected accordingly.
| What was added or changed | Example |
|---|---|
| Previously unaccounted losses | circulation and distribution losses of hot water |
| Changed consumption | the move to LED lighting |
| Effect of the heating solution | accounting for electric underfloor heating |
| Cooling | the need to promote passive cooling solutions |
| Climate data | the normal-year degree-day dataset was updated |
The justification is direct: the climate has changed, heatwaves have become more frequent and average temperatures have risen. The better these conditions are anticipated in the calculations, the more reliable the energy certificates are.
4. What it means in practice
Three consequences affect every project, including the most routine. They concern the class, the calculation and the documents.
An earlier limit value cannot be used, even where the project is similar, and the result of an earlier calculation is not directly transferable, because the methodology itself changed. The applicable version is determined by the application date, as covered by the article on the date rule.
The third point means that in 2025 and 2026 projects are running under two different versions, and confusing them is a real risk, all the more so because the documents look identical. The application date decides which applies.
5. Why requirements are updated periodically
One principle explains the future as well as the past. Requirements tighten step by step.
According to information published by the Ministry of Climate, minimum energy performance requirements for buildings must be updated in the European Union every five years, to keep pace with technological developments, and the update rests on cost-optimal level calculations. The review follows a fixed interval.
The current values are therefore not final, and the next update is known as a principle although not as a date. Professionally the conclusion is that memorising limit values is not a sensible strategy.
Summary and four practical rules
On 1 June 2025 the class scale, the limit values, the calculation methodology and the scope changed at once, and three regulations were amended. The change of scale follows from European harmonisation rather than from a tightening of Estonian requirements, and the methodology gained previously unaccounted losses, LED lighting, electric underfloor heating, passive cooling and updated climate data. Existing certificates remained valid.
Four rules: do not carry an earlier calculation into a new project, because the methodology changed. Fix the application date, since it determines the version. Allow for projects running under two versions at once. Do not memorise limit values, since they are updated every five years.
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.