Topic
Reading and understanding the energy certificate
The energy certificate is the one document a seller has to produce before you even view the property. Almost nobody reads it, yet it states what the building costs to run and what you may have to do once you own it.
Demand-based or consumption-based: the difference changes everything
There are two kinds, and they say different things. One calculates what the building would need under standardised use. The other measures what the previous occupants actually used. A frugal tenant can make a poor building look good on paper.
The demand-based certificate
It rates the fabric itself: insulation, windows, heating. For a buyer it is the more meaningful of the two, because it does not depend on who lived there before.
The consumption-based certificate
It takes the last few years of bills. Two people in a large house produce a good figure even if the building itself is poorly insulated.
How long it stays valid
The certificate carries a fixed validity period. Once it expires it is worthless, and the seller has to commission a new one before the listing goes live. The date sits on the cover page and almost nobody checks it.
What can follow after you buy
Several countries attach a duty to a poor rating: certain building elements have to be upgraded within a set period after a change of ownership, and an old boiler may no longer be kept running. That duty falls on the buyer, not the seller.
What a poor rating actually costs you
It costs twice: in running costs and in financing. Several banks now tie their terms to the energy class, and in some countries a property below a certain class may no longer be let out at all.
The legal position in Germany
The energy certificate
On a sale, the seller must show and hand over a valid energy certificate (either a demand-based or a consumption-based one) to the buyer. Listings must state the energy indicator and the efficiency class, on a scale from A+ to H. Since the Gebäudemodernisierungsgesetz (GModG), the consumption-based certificate is only permitted for a building used exclusively for residential purposes.
What you must retrofit after buying
There is no general mandatory retrofit tied to the efficiency class. Duties triggered by a change of ownership do remain: a new owner must insulate the top-floor ceiling or the roof (section 35 GModG) and insulate accessible heating and hot-water pipes in unheated spaces (section 69(3) and (4) GModG), usually within two years of the purchase. The earlier duty to replace a constant-temperature boiler over 30 years old has been abolished outright since 29 July 2026, with nothing put in its place.
Basis: The Gebäudemodernisierungsgesetz (GModG), which replaced the Gebäudeenergiegesetz (GEG) on 29 July 2026; the energy certificate is still covered in its own section, the retrofit duties in sections 35, 36 and 69. Last checked against the legal text: 2026-08-17.
The legal position in Austria
The energy certificate
The seller must present and hand over to the buyer an Energieausweis (energy certificate) that is at most ten years old. Advertisements must state the Heizwärmebedarf (heating energy demand, HWB) and the Gesamtenergieeffizienz-Faktor (overall energy efficiency factor, fGEE). If the Energieausweis is missing, at least an overall energy efficiency corresponding to the age and type of the building is deemed to have been agreed.
What you must retrofit after buying
There is no nationwide compulsory renovation obligation based on energy class. Requirements regarding thermal quality arise only during major renovations and derive from OIB-Richtlinie 6 and the Bauordnungen (building codes) of the federal provinces.
Basis: Legal basis is the Gesetz über die Pflicht zur Vorlage eines Energieausweises (Energieausweis-Vorlage-Gesetz 2012, EAVG 2012). Technical requirements are set out in OIB-Richtlinie 6.. Last checked against the legal text: 2026-08-19.
The legal position in Switzerland
The energy certificate
The cantonal building energy certificate (Gebäudeenergieausweis der Kantone, GEAK) rates a building from A to G by how much energy it needs in normal operation. It is voluntary in principle, but several cantons make it mandatory. Fribourg requires it on a change of ownership. Vaud requires its French-language equivalent, the CECB, since 1 January 2017, both when selling an existing residential building and when replacing a heating system with a new fossil-fuel one. Basel-Stadt operates a 'GEAK Plus', triggered by an old fossil heating system rather than by a sale, under its 2017 Energy Act. Geneva and Zurich, often assumed to require it, do NOT: for a private sale, both only recommend one.
What you must retrofit after buying
There is no nationwide mandatory renovation. Requirements for energy retrofits and the share of renewable energy are set by the cantons individually, and they differ from canton to canton. They are loosely coordinated through the Model Cantonal Energy Provisions (Mustervorschriften der Kantone im Energiebereich, MuKEn), an advisory template rather than federal law: each canton adopts it voluntarily and at its own pace. The 2025 edition replaced the 2014 one on 29 August 2025 with stricter rules, but the cantonal conference gives a horizon out to 2030 for adoption, with individual cantons such as St. Gallen not until 2031, so the 2014 edition still underlies the law in many cantons as of August 2026.
Basis: Cantonal law: each canton regulates this under its own energy act, loosely coordinated through the Model Cantonal Energy Provisions (MuKEn) of the cantonal energy directors' conference (EnDK), 2025 edition adopted 29 August 2025, superseding the 2014 edition; Vaud's Règlement sur le CECB (RSV 730.01.4); Zurich's cantonal building-energy rules on heating replacement; Basel-Stadt's 2017 Energy Act and its parliament's January 2023 decision to close the gas network by 2037; federal CO2 Act, in force since 2025, for the Buildings Programme.. Last checked against the legal text: 2026-08-19.
The legal position in 30 further countries
This theme also has a legal basis on record for these countries, each with its statute and verification date. Expand your country.
Belgium
The energy certificate
The energy certificate is regulated regionally: the Energieprestatiecertificaat (EPC) in Flanders, the PEB in Wallonia and Brussels. It is mandatory at sale, and the rating has to appear in the listing.
What you must retrofit after buying
Flanders has a genuine renovation duty: buying a residential building rated E or F from 2023 onward means bringing it up to at least band D within five years of the purchase, or six years for a purchase from 1 January 2026 onward. Missing the deadline risks an administrative fine of 500 to 5,000 euros and a new deadline is then set. That is a direct risk you take on at the moment of buying. Wallonia follows the same underlying principle but on its own, later timetable (from September 2028, after a delay decided in December 2025); Brussels instead relies on a rental ban from band F and G, with band E as the minimum.
Basis: In Flanders, the Vlaams Energiedecreet and the Energiebesluit (Renovatieverplichting) govern this; Wallonia and Brussels each set their own regional rules.. Last checked against the legal text: 2026-08-17.
Bulgaria
The energy certificate
An energy certificate (sertifikat za energiyni harakteristiki) is mandatory for sale and for a rental term exceeding one year, and must be presented to the buyer.
What you must retrofit after buying
There is no building-specific compulsory refurbishment based on energy class.
Basis: The legal basis is the Zakon za energiynata efektivnost (ZEE).. Last checked against the legal text: 2026-08-19.
Denmark
The energy certificate
The energy label (energimærke) with classes A to G must be available before a building over 60 m² is offered for sale or rent, and must be presented to the buyer. It is valid for ten years.
What you must retrofit after buying
There is no building-specific compulsory renovation by class.
Basis: Energimærkningsloven, the Act on the Promotion of Energy Savings in Buildings (Lov om fremme af energibesparelser i bygninger). Last checked against the legal text: 2026-08-19.
Estonia
The energy certificate
The energy performance certificate (energiamärgis) with classes A to H is mandatory on sale and on letting for consideration, and must be presented to the acquirer. The certificate based on actual consumption is valid for ten years.
What you must retrofit after buying
There is no building-specific compulsory renovation by class.
Basis: Estonian Law on Construction (Ehitusseadustik) together with the ordinance on the requirements for the energiamärgis.. Last checked against the legal text: 2026-08-19.
Finland
The energy certificate
An energy certificate (energiatodistus) with classes A to G is mandatory on sale and lease. The class must be stated in the listing, and the certificate must be provided to the buyer.
What you must retrofit after buying
There is no building-specific compulsory renovation based on energy class.
Basis: Legal basis: Laki rakennuksen energiatodistuksesta (50/2013).. Last checked against the legal text: 2026-08-19.
France
The energy certificate
The energy certificate (Diagnostic de Performance Énergétique, DPE), rated A to G, is mandatory at sale and must be available to the buyer from the listing onward. The DPE is legally binding (opposable): the buyer can rely on it directly. WATCH THE DATE: on 1 January 2026 the calculation method itself changed (a new conversion factor for electricity into primary energy), and around 850,000 homes moved up a class without any renovation at all, mostly from G to F and from F to E. A better rating since that date does not necessarily mean real building work was done.
What you must retrofit after buying
France is phasing the worst-rated homes (passoires thermiques) out of the rental market step by step: band G can no longer be let from 1 January 2025, band F follows in 2028 and band E in 2034. A poor rating means letting without renovation is already banned or soon will be. Selling a house or a building in sole ownership rated E, F or G also requires an energy audit (audit énergétique) — NOT an ordinary flat in a co-owned building (copropriété) — required for F and G since 1 April 2023 and for E as well since 1 January 2025. That audit document is only valid for five years, shorter than the DPE itself.
Basis: Enacted by the Loi Climat et Résilience of 22 August 2021, implemented through the Code de la construction et de l'habitation.. Last checked against the legal text: 2026-08-17.
Greece
The energy certificate
The energy certificate (Pistopoiitiko Energeiakis Apodosis, PEA) with classes A+ to H is mandatory for every sale, lease, and advertisement. The seller must present a valid PEA to the notary before notarization. It remains valid for ten years, and failure to produce it carries a fine of 1,000 to 10,000 Euro.
What you must retrofit after buying
There is no compulsory renovation of individual buildings based on energy class.
Basis: Law 4122/2013 on the overall energy efficiency of buildings.. Last checked against the legal text: 2026-08-19.
Ireland
The energy certificate
Building Energy Rating (BER), scale A1 to G, issued by an assessor registered with SEAI and valid for ten years. Mandatory on sale AND on letting: the BER rating must appear in EVERY advertisement, and the BER together with the Advisory Report must be handed to the buyer or tenant before conclusion. Every certificate can be verified publicly in the SEAI BER register using the MPRN (Meter Point Reference Number).
What you must retrofit after buying
Ireland has NO ban on letting from a certain rating, unlike France or Flanders. A poor rating therefore prohibits neither sale nor letting. The impact is on costs: grants are administered by SEAI, including the One Stop Shop and the Warmer Homes Scheme for low-income households. Where a figure is stated in the dossier, it is stated as a grant, not as an obligation.
Basis: European Union (Energy Performance of Buildings) Regulations 2012 (S.I. No. 243 of 2012). A breach of the BER obligation is a criminal offence carrying a fine of up to EUR 5,000 per case, prosecuted by the local Building Control Authority.. Last checked against the legal text: 2026-08-19.
Iceland
The energy certificate
No energy certificate system for sale or lease was found. The building regulation Byggingarreglugerð nr. 112/2012, Part 13, was read in full (around 3,900 lines) and does not contain the term orkuvottorð (energy certificate) or any recognizable equivalent at any point. Part 13 exclusively regulates technical construction requirements, namely U-values, insulation standards, and total energy demand, for new buildings, and contains no disclosure obligation for sale or lease. This negative finding is solidly evidenced. The frequently cited justification, that Iceland holds an EEA exception from EU-Gebäuderichtlinie 2010/31/EU, was not verified. The primary text of any potential decision by the Joint EEA Committee could not be reached by any attempted route: efta.int returned a 403 error, and eur-lex.europa.eu blocked access with a JavaScript verification page. This justification remains a preliminary working hypothesis, not a verified legal situation.
What you must retrofit after buying
No duty was researched because no energy certificate system exists to which a class-based duty could attach.
Basis: Byggingarreglugerð nr. 112/2012, Part 13 (negative finding, full text read and searched for 'orkuvottorð'). Last checked against the legal text: 2026-08-19.
Italy
The energy certificate
An energy performance certificate (Attestato di Prestazione Energetica, APE) with ratings from A4 to G is mandatory on sale and must be attached to the purchase contract. The key energy indicators must be stated in any advertisement.
What you must retrofit after buying
There is no nationwide mandatory renovation tied to a specific energy class. Energy efficiency requirements apply to major renovation work and to new buildings.
Basis: Decreto Legislativo 192/2005 on the overall energy efficiency of buildings, Art. 6, which requires the APE to be submitted on sale.. Last checked against the legal text: 2026-08-19.
Croatia
The energy certificate
The energetski certifikat (energy certificate) with classes A+ to G is mandatory for the sale of a property over 50 m² and must be presented to the buyer. It is valid for ten years.
What you must retrofit after buying
There is no building-specific mandatory renovation requirement tied to an energy class.
Basis: The legal basis is provided by the Zakon o energetskoj učinkovitosti and the Zakon o gradnji.. Last checked against the legal text: 2026-08-19.
Latvia
The energy certificate
An energy certificate (ēkas energosertifikāts) is mandatory for sale and lease, and advertisements must indicate the building's energy performance values.
What you must retrofit after buying
There is no building-specific compulsory renovation based on energy class.
Basis: Ēku energoefektivitātes likums (Latvian law on building energy efficiency). Last checked against the legal text: 2026-08-19.
Liechtenstein
The energy certificate
Obligation on the sale, letting, or leasing of a building: the seller, landlord, or lessor must present to the purchaser, tenant, or lessee, no later than the submission of the contractual declaration, an energy certificate that is at most ten years old at that time, and must hand it over upon conclusion of the contract (Art. 4 Abs. 1 EnAG). Two separate obligations at two points in time: presentation by the time of the contractual declaration, handover upon conclusion of the contract. Exceptions (Art. 2 Abs. 2): heritage-protected buildings insofar as the protected character would otherwise be unacceptably impaired, buildings used for worship, provisional buildings with a planned useful life of up to two years, industrial and commercial buildings, agricultural buildings with low energy demand, detached buildings with a total usable floor area of less than 50 m².
What you must retrofit after buying
No obligation to renovate or to let coupled to the energy class was found; the EnAG regulates only the duty to present and hand over the certificate itself, with no consequence for a poor class.
Basis: Energieausweisgesetz (EnAG) of 23 May 2007, LGBl. 2007 No. 190, LR 701.1, Art. 2, 4, 8 (fines up to 5,000 francs).. Last checked against the legal text: 2026-08-19.
Lithuania
The energy certificate
The energy certificate (pastato energinio naudingumo sertifikatas), with efficiency classes A++ to G, is mandatory on sale and lease. The owner must present it to the buyer, and the key figures must be stated in the advertisement. It remains valid for ten years.
What you must retrofit after buying
There is no building-specific compulsory renovation to achieve a specified class.
Basis: Lithuanian Law on Construction (Statybos įstatymas) together with the building regulation on energy efficiency of buildings.. Last checked against the legal text: 2026-08-19.
Luxembourg
The energy certificate
An energy performance certificate (Certificat de Performance Énergétique, CPE) is mandatory on sale and on letting, and must be provided to the buyer or tenant. It remains valid for at most ten years. Anyone who fails to provide it faces imprisonment from eight days to two months and/or a fine from 61 to 24,789 Euro. This is the general penalty range des Gesetzes von 1993 for violations of the certificate obligation, not a separate, lower scale der Verordnung von 2021.
What you must retrofit after buying
There is no building-specific compulsory renovation by class.
Basis: The applicable instrument is the Règlement grand-ducal vom 9. Juni 2021 über die Gesamtenergieeffizienz von Gebäuden. Penalties are governed by Art. 20 des geänderten Gesetzes vom 5. August 1993 über die rationelle Energienutzung, with a range of 61 to 24,789 Euro.. Last checked against the legal text: 2026-08-19.
Malta
The energy certificate
An Energy Performance Certificate (EPC) is mandatory when selling, letting and in advertisements, and must be shown to the purchaser before the promise of sale at the latest. It is valid for ten years.
What you must retrofit after buying
There is no building-specific compulsory renovation based on class.
Basis: Energy Performance of Buildings Regulations, issued as Legal Notice 47 of 2018. Last checked against the legal text: 2026-08-19.
Netherlands
The energy certificate
The Energielabel (energy label, classes A+++++ to G) is mandatory on sale, letting, and handover. The seller must provide the buyer with a valid label; otherwise the seller faces a fine.
What you must retrofit after buying
There is no general compulsory renovation obligation for dwellings. For office buildings, a minimum requirement of at least Energielabel C has applied since 2023. If this requirement is not met, use as an office is not permitted.
Basis: The statutory basis is the Besluit bouwwerken leefomgeving (Bbl) under the Omgevingswet. The earlier basis, the Besluit energieprestatie gebouwen (BEG) based on the Woningwet, was superseded by the Omgevingswet.. Last checked against the legal text: 2026-08-19.
Norway
The energy certificate
The seller must present the energiattest (energy certificate) before the purchase contract is concluded, and it must be displayed in the advertisement. Detached buildings under 50 m² are exempt.
What you must retrofit after buying
There is no building-specific compulsory renovation based on class.
Basis: Energimerkeforskriften (Forskrift 2009-12-18-1665), based on the energiloven.. Last checked against the legal text: 2026-08-19.
Poland
The energy certificate
An energy certificate (świadectwo charakterystyki energetycznej) has been mandatory for sale and letting since 28 April 2023. The seller must hand it over to the buyer. If it is missing, legal consequences arise.
What you must retrofit after buying
There is no building-specific compulsory renovation based on energy class.
Basis: Act on the Energy Performance of Buildings of 29 August 2014 (Ustawa o charakterystyce energetycznej budynków). Last checked against the legal text: 2026-08-19.
Portugal
The energy certificate
An energy certificate (Certificado Energético) issued under the Sistema de Certificação Energética (SCE), with efficiency classes from A+ to F, is mandatory on sale. The SCE number must appear in every advertisement, and the certificate must be handed to the buyer before signing the preliminary contract (Contrato de Promessa de Compra e Venda, CPCV).
What you must retrofit after buying
There is no class-based compulsory renovation for individual buildings. The requirements apply only to new construction and major renovation.
Basis: Decreto-Lei 101-D/2020 on energy efficiency requirements for buildings and the energy certification system (SCE), as currently in force: amended by Decreto-Lei 102/2021 and by Decreto-Lei 11/2025, which partially transposes the EPBD recast (EU) 2024/1275.. Last checked against the legal text: 2026-08-19.
Romania
The energy certificate
The energy performance certificate (certificat de performanță energetică) is mandatory for sale and lease. The owner must provide the buyer with a copy before conclusion of the contract and hand over the original to the new owner upon purchase.
What you must retrofit after buying
There is no mandatory building-specific renovation linked to an energy performance class.
Basis: Law No. 372/2005 on the overall energy efficiency of buildings (Legea nr. 372/2005). Last checked against the legal text: 2026-08-19.
Sweden
The energy certificate
The seller must provide the energideklaration (energy declaration), with classes A to G, no later than at the time of sale, and it must be at most ten years old. If the seller fails to do so despite a request, the buyer may, within six months after taking possession, have one prepared at the seller's expense.
What you must retrofit after buying
There is no building-specific compulsory renovation requirement based on class.
Basis: Lag (2006:985) om energideklaration för byggnader, the Act on Energy Performance Certificates for Buildings. Last checked against the legal text: 2026-08-19.
Serbia
The energy certificate
The energy certificate (energetski pasoš, sertifikat o energetskim svojstvima zgrade) is required for the sale or purchase of real estate, and it forms part of the technical acceptance for the use permit. It may only be issued by authorized bodies.
What you must retrofit after buying
There is no building-specific compulsory renovation according to class.
Basis: The legal basis is the Law on Planning and Construction (Zakon o planiranju i izgradnji) together with the Regulation on the Issuance of Energy Certificates for Buildings (Pravilnik o sertifikatu o energetskim svojstvima zgrada).. Last checked against the legal text: 2026-08-19.
Slovakia
The energy certificate
An energy certificate (energetický certifikát) with classes A to G is required for sale and for letting to a new tenant, as well as for new construction and major renovation.
What you must retrofit after buying
There is no building-specific compulsory renovation based on class. Requirements apply to new construction and major renovation.
Basis: Act on the Energy Performance of Buildings (Zákon č. 555/2005 Z. z. o energetickej hospodárnosti budov). Last checked against the legal text: 2026-08-19.
Slovenia
The energy certificate
An energy performance certificate (energetska izkaznica) is required for sale and for letting where the term is one year or more. The owner must present it to the buyer or tenant at the latest before the contract is concluded, and the class must be stated in the advertisement.
What you must retrofit after buying
There is no building-specific compulsory renovation based on the energy class.
Basis: Energetski zakon (EZ-1), 334. člen on the obligations for the energy performance certificate.. Last checked against the legal text: 2026-08-19.
Spain
The energy certificate
The energy certificate (Certificado de Eficiencia Energética, CEE) with classes A to G is mandatory on sale and must be available from the time the property is advertised. The class must be stated in advertisements.
What you must retrofit after buying
There is no nationwide compulsory renovation based on class. Energy efficiency requirements apply to major renovations under the technical building code (Código Técnico de la Edificación).
Basis: Real Decreto 390/2021 on the basic procedure for certifying the energy efficiency of buildings. Last checked against the legal text: 2026-08-19.
Czechia
The energy certificate
An energy performance certificate (Průkaz energetické náročnosti budovy, PENB, Czech building energy performance certificate) with classes A to G is mandatory for sale and lease. The seller must provide it to the buyer, and it may be at most ten years old.
What you must retrofit after buying
There is no building-specific compulsory renovation requirement based on energy class.
Basis: The applicable statute is Zákon č. 406/2000 Sb. o hospodaření energií.. Last checked against the legal text: 2026-08-19.
Hungary
The energy certificate
The energy certificate (energetikai tanúsítvány) is mandatory when selling or letting, and the energy class must be stated in the advertisement. Validity was reduced from ten years to five years.
What you must retrofit after buying
There is no building-specific mandatory renovation based on class.
Basis: 176/2008. (VI. 30.) Korm. rendelet az épületek energetikai jellemzőinek tanúsításáról. Last checked against the legal text: 2026-08-19.
United Kingdom
The energy certificate
The Energy Performance Certificate (EPC), rated A to G, is mandatory at sale and at letting and must be available to the buyer. The rating has to appear in the listing.
What you must retrofit after buying
In the private rented sector you may only let a home rated E or better (the Minimum Energy Efficiency Standard, MEES); a rating of F or G risks a fine of up to £5,000. A tightening to at least band C takes effect on 1 October 2030, with a £10,000 cost cap on the work needed. The underlying measurement itself is changing too: from late 2027 the new Home Energy Model (HEM) becomes available alongside the current EPC score, and from 1 October 2029 HEM becomes the sole standard. An owner-occupier faces no retrofit duty.
Basis: The Energy Performance of Buildings (England and Wales) Regulations 2012; the rental standard follows the Energy Efficiency (Private Rented Property) Regulations 2015.. Last checked against the legal text: 2026-08-17.
Cyprus
The energy certificate
The Energy Performance Certificate (EPC) must be available before a sale or letting and must be presented to the buyer. If it is missing, fines and legal consequences may result.
What you must retrofit after buying
There is no building-specific compulsory renovation requirement based on energy class.
Basis: Energy Performance of Buildings Law, Gesetz 142(I)/2006. Last checked against the legal text: 2026-08-19.
Frequently Asked Questions
Does the seller have to show the certificate without being asked?
Yes. The duty to produce it applies at the latest at the viewing, and the key figures already have to appear in the listing. Anyone who only sees it at completion has a fair signal about how carefully the rest of the paperwork was kept.
Can I challenge the certificate?
It is not a guarantee, but a professional assessment under a prescribed method. If reality diverges sharply, that points to an error in how it was produced, not necessarily a defect in the building.
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