Buyers arriving from the United States, the United Kingdom or France expect a Lisbon purchase to include an electrical assessment, because at home one exists: a home inspection with an electrical section, an EICR, or the electrical diagnostic inside the French dossier de diagnostic technique. Portugal has none of these for housing. Decreto-Lei n.º 96/2017 places residential installations outside mandatory periodic inspection, so no authority checks the installation and no certificate exists for a seller to hand over. The regulatory position is set out in the guide to electrical inspection in Portugal. This guide answers the question that follows it: in a Lisbon apartment, what does an older installation hide, and how does a buyer get it examined when there is nothing to book.
Table of Contents
- Can you book an electrical inspection for a Lisbon apartment?
- What does the installation's age predict?
- Why is a Lisbon apartment rarely one installation?
- Which documents exist, and what does their absence tell you?
- How do you get the electrical scope covered?
- Frequently Asked Questions
Can you book an electrical inspection for a Lisbon apartment?
Portugal has no standalone residential electrical inspection and no periodic certificate, because Decreto-Lei n.º 96/2017 excludes housing from mandatory periodic oversight.
The short answer is that the thing the search phrase describes does not exist as a product in Portugal, and the reason is regulatory rather than commercial.
Decreto-Lei n.º 96/2017 builds the inspection regime around installations that receive the public or carry significant load. Standard residential installations sit outside the mandatory periodic requirement. The technical rules themselves, the Regras Técnicas das Instalações Elétricas de Baixa Tensão set by Portaria n.º 949-A/2006 and amended by Portaria n.º 252/2015, apply to every new or renovated installation. What is missing is anyone whose job is to come back and check.
Three consequences follow, and they are the ones that matter to a buyer:
- There is no residential equivalent of the gas inspection certificate. A seller can produce a gas boletim because the law creates one. There is no electrical counterpart to ask for.
- There is no Portuguese EICR. The comparison with source markets is set out in the guide to mandatory diagnostics in Portugal against Europe.
- Since Decreto-Lei n.º 10/2024, de 8 de janeiro removed municipal verification from the deed on 1 January 2024, nothing in the transaction looks at the installation before completion. The mechanics are in the Simplex Urbanístico guide.
The electrical assessment therefore happens in one place only: inside a pre-purchase or technical inspection the buyer arranges. Section five covers how to brief it.
What does the installation's age predict?
The installation's original date predicts whether the design included protective earthing, differential protection and enough circuits for a modern electrical load.
Age is a useful variable, and it is useful for a narrower set of questions than buyers assume. It answers three.
Was there a protective earth in the original design? Older Portuguese residential installations were frequently built without a continuous earthing system connecting the board to a proper earth electrode. This is the finding with the widest safety consequence, and it is the one that visual inspection cannot settle: continuity is measured, not observed.
Was there differential protection? High-sensitivity residual current protection, the 30 mA differential, is a modern RTIEBT requirement. Boards that predate it often have none, or carry a single low-sensitivity device covering the whole installation rather than dedicated protection on the circuits that need it.
Was the circuit count designed for today's load? An installation laid out for lighting and a small number of sockets is now asked to carry an induction hob, air conditioning, a heat pump and, in a growing number of Lisbon buildings, a vehicle charger. A board that trips under normal use is reporting this.
There is a fourth question age does not answer, and it is the one that decides the risk: is any of the original installation still there? A 1970s building tells you what was installed in the 1970s. It tells you nothing about the four interventions since.
Why is a Lisbon apartment rarely one installation?
Lisbon resale stock has been renovated in overlapping partial interventions, so a single apartment commonly contains wiring from several dates under one board.
This is the difference between a Lisbon apartment and the mental model a foreign buyer brings, and it is the answer to what an older installation hides.
In markets where housing turns over slowly and renovations are permitted and documented, an installation tends to have a date. Lisbon's resale stock does not work that way. Apartments in the central parishes have passed through multiple owners, short-term letting conversions, kitchen and bathroom refits, and the addition of air conditioning, each intervention touching part of the installation and leaving the rest alone.
The result is a composite. One circuit was rewired in a bathroom refit and is compliant. The circuit next to it was not touched and dates from the original build. The board was replaced, which makes the whole installation look modern, while most of what runs behind the plaster is unchanged. A replaced board on unchanged wiring is the single most misleading thing a buyer sees at a viewing, because it presents as evidence of an upgrade that did not happen.
Layering also defeats the shortcut buyers reach for. The building's construction date is public, and it is treated as a proxy for the installation. In a composite installation there is no single date to find, and the only way to establish what is present is to test the circuits rather than read the building's year.
For the wider defect profile of Lisbon apartments across structure, moisture and MEP, the Lisbon apartment inspection guide sets out the full scope.
Which documents exist, and what does their absence tell you?
Two documents can exist for a Portuguese residential installation, the termo de responsabilidade for an intervention and the ficha técnica da habitação for post-2004 construction.
Because there is no periodic certificate, the paper trail is made of one-off records, and knowing which ones could exist turns a vague question into a specific request.
The termo de responsabilidade or declaração de conformidade. Where a residential installation up to the standard supply threshold is newly connected or renovated, the installing technician issues a term of responsibility rather than the property receiving a full inspection by an accredited body. For any past intervention there should in principle be one. An apartment marketed as renovated, whose owner cannot produce a term of responsibility for the electrical work, is telling a buyer that the work was either undocumented or carried out by someone not in a position to sign for it.
The ficha técnica da habitação. Required for properties built, reconstructed or extended from 30 March 2004 under Decreto-Lei n.º 68/2004, de 25 de março, it describes the systems the property was built with. For a Lisbon apartment older than that, which is most of the resale stock, no such record was ever created.
And for everything else, nothing. This is the honest position. A pre-2004 apartment with undocumented interventions has no record of its electrical installation anywhere, and no authority is holding one. The document a buyer can still obtain is the one they commission, which the guide to what a property condition report contains describes.
Across Portugal 35.8% of buildings need repair, split into 21.8% light, 9.4% medium and 4.6% deep (INE, Censos 2021), giving 14% with serious condition problems. Electrical installations are not counted separately in that survey, which is itself part of the picture: the national statistics measure the fabric, and the systems inside it are recorded nowhere.
How do you get the electrical scope covered?
The electrical assessment sits inside a pre-purchase inspection by an engineer registered with the Ordem dos Engenheiros, and the brief sets its depth.
Since there is nothing to book on its own, the practical question is what to ask for and what a report should come back with.
Ask for the electrical installation to be named in the scope. A pre-purchase inspection covers the installation, and a buyer who wants weight on it should say so when arranging the visit rather than assume the default depth.
Ask for the earthing to be tested rather than observed. Continuity is the finding that cannot be reached any other way, and it is the one most likely to change what a buyer does.
Ask for differential protection to be verified by circuit, not by presence. A differential in the board is not the same as a differential covering the circuits that require one.
Ask what the board serves. The relationship between the number of circuits, their protection and the load the apartment now carries is the practical measure of whether the installation has kept pace with the property.
Ask for the findings to be graded and dated. A finding recorded with a severity rating in a report signed by an engineer with a cédula number is usable in a negotiation before the Contrato-Promessa de Compra e Venda is signed. The same observation made afterwards is a conversation. What a pre-purchase inspection covers sets out the rest of the scope.
One point deserves stating plainly and it applies whatever the findings are. Nothing in an electrical installation should be altered by the buyer or the seller informally in response to a report. Work on an installation by anyone not qualified to sign for it removes the certification from whoever has to take responsibility afterwards, and it makes a resolvable finding harder to resolve.
Need the document layer before the site visit? RealOS reads the legal and valuation picture of a property from its records, without an inspector attending. → realos.pt
Frequently Asked Questions
Does the age of the building tell me the age of the electrical installation?
No, and treating it as a proxy is the most common error. The construction date establishes what standards applied when the building was new. In Lisbon's resale stock most apartments have been partially rewired across several interventions, so the installation is a composite of dates rather than a single vintage. Only testing establishes what is present.
The apartment was renovated last year. Is the electrical installation new?
Not necessarily, and a recent renovation frequently touches only part of the installation. Kitchen and bathroom refits commonly rewire the circuits in those rooms and leave the rest as found. A new consumer unit fitted during a cosmetic renovation makes the installation look current while the wiring behind the walls is unchanged.
What should I ask the seller about electrical work?
Ask which interventions have been carried out, on what dates, and whether a termo de responsabilidade exists for each. For a property built, reconstructed or extended from 30 March 2004, ask for the ficha técnica da habitação under Decreto-Lei n.º 68/2004. A specific question about a specific document produces a verifiable answer.
Is an old installation a reason to walk away from a Lisbon apartment?
Rarely on its own. An older installation is a scope and cost question rather than a disqualifying defect, and it is one of the more predictable items to price once it has been assessed. What turns it into a problem is discovering it after the deed, when Decreto-Lei n.º 10/2024 has already transferred the position to the buyer and there is no seller obligation to fall back on.
Conclusion
A buyer searching for an electrical inspection in Lisbon is looking for something their own market provides and Portugal does not. No authority inspects a residential installation, no certificate is issued for one, and since January 2024 nothing in the transaction examines the building at all.
What an older Lisbon installation hides is not usually its age. It is the layering: several interventions of different dates under one board, with a modern front end and unchanged wiring behind it. Establishing which is which takes testing, and the assessment happens inside a pre-purchase inspection carried out by an engineer registered with the Ordem dos Engenheiros, arranged while the price is still open.
→ Book a Pre-Purchase Inspection · get a quote at inspectos.pt/en/home-inspections
Updated September 2026 | Reviewed by the InspectOS engineering team, engineers registered with the Ordem dos Engenheiros | InspectOS Portugal · Legal position verified 17 September 2026
Sources: Decreto-Lei n.º 96/2017, de 18 de agosto · Portaria n.º 949-A/2006, de 11 de setembro (RTIEBT), amended by Portaria n.º 252/2015 · Decreto-Lei n.º 68/2004, de 25 de março · Decreto-Lei n.º 10/2024, de 8 de janeiro · Direção-Geral de Energia e Geologia · INE, Censos 2021 · Ordem dos Engenheiros · Diário da República.