A renovated home is often the easier purchase: new kitchen, new bathroom, fresh paint, nothing to do on day one. The question is what the seller changed behind the finishes, and whether the works left a paper trail you can read. Under the Regime Jurídico da Urbanização e Edificação (RJUE), some works need a licence, some a comunicação prévia and some neither, and each route leaves different documents. Since Decreto-Lei n.º 10/2024 the notary no longer checks the licence at the deed, and nobody compares the building with it; our guide to the Simplex Urbanístico explains that change. This guide covers the works themselves: what to ask the seller for, what your lawyer reads, and what an InspectOS Pre-Purchase Inspection records on site before you sign the CPCV.
Table of Contents
- What did the seller actually change?
- What can a viewing tell you about the works, and what can't it?
- Which works needed a licence, a comunicação prévia or nothing at all?
- What paper trail should the works have left?
- What does an inspection check in the renovated rooms?
- Who checks what before the CPCV?
- Frequently Asked Questions
What did the seller actually change?
A renovation changes what the documents describe; the buyer's first task is to list each change the seller made, with dates, before deciding anything about price.
In a recent house we inspected in 2026, the former pergola had been enclosed to create a bedroom with a bathroom. The engineer recorded settlement of the foundation in that area, with related cracking, and linked it to the loads the works had added. It is one case, and that report did not look at whether the works were licensed. What it shows is the kind of question a renovation raises: the new room looked finished, and the building under it was reacting to it.
Most renovations are less dramatic. A wall comes out to open the kitchen to the living room, a bathroom moves, windows are replaced, a terrace is closed in, an attic becomes a bedroom. Each of these changes one of three things: the structure that carries the building, the envelope that keeps water out, or the layout the documents describe. A buyer does not need to judge any of them at the viewing. A buyer needs a list.
Ask the seller, in writing and before the offer, for every work done during their ownership and any they know of from before: what was done, when, by whom, and under which municipal procedure, if any. The answers decide what you ask your lawyer to read and what you ask an engineer to look at.
What can a viewing tell you about the works, and what can't it?
A viewing shows finishes and layout; it cannot show what was removed behind them, how loads were redistributed, or whether new pipes and waterproofing were done properly.
New finishes are designed to look the same whether the work underneath was careful or not. Plaster and paint cover where a wall used to be. Tiles cover the waterproofing of a moved shower. A new ceiling covers the beam, or the absence of one, that took over from a removed wall.
What you can read at a viewing is the layout against the plans, if you have them, and the edges of the work: the line where new floor meets old, a ceiling that drops in one room, a doorway in a wall that looks too thin to have carried anything. Our guide to checking for illegal extensions covers what you can see from the street and in listing photographs. Inside, the signs worth noting are fine cracks running from the corners of new openings, doors that stick in a frame that used to close, damp at the foot of walls next to a relocated bathroom, and a strong smell of fresh paint in one room only.
In older Lisbon buildings this matters more than the finish suggests. In a gaioleiro or Pombaline building, interior walls can be part of how the building resists load, and removing one is a structural change. Our guide to Pombaline and gaioleiro buildings explains how those systems work.
Which works needed a licence, a comunicação prévia or nothing at all?
The RJUE sorts works into licença, comunicação prévia and exempt works; interior changes that touch the structure are exempt only with a stability project and a signed technical declaration.
Under Article 4.º of the RJUE (Decreto-Lei n.º 555/99, as amended, most recently by Decreto-Lei n.º 108/2026, in force since 1 October 2026), urban works depend on a licence (licença), a comunicação prévia, or a comunicação prévia com prazo. Construction, alteration and extension works need a licence unless the law places them under comunicação prévia, for example in an area covered by a detailed plan or a loteamento that fixes the building parameters, or in a consolidated urban area where the works respect the municipal plan and the prevailing façade height (Art. 4.º n.ºs 2 and 4). A swimming pool attached to the main building goes through comunicação prévia (Art. 4.º n.º 4 j)).
Article 6.º lists the works exempt from both. The ones that matter most in a renovated home:
- Conservation works, such as repairs and repainting (Art. 6.º n.º 1 a)).
- Interior alteration works that do not change the exterior (heights, façades, roofs) and do not affect the stability of the building. Interior works that do affect stability are exempt only if they come with a stability project and a termo de responsabilidade (technical statement of responsibility) from a qualified technician declaring that the works, as a whole, improve or do not harm the structure, plus a seismic reinforcement project where the law requires one (Art. 6.º n.º 1 b)).
- Works of minor urban relevance (obras de escassa relevância urbanística, Art. 6.º-A), such as a small annex of up to 10 m² that does not front the public road, boundary walls up to 1.8 m that do not front the public road, solar panels within set limits, or replacement window frames that improve energy efficiency while keeping the original geometry and appearance.
Two points stop "exempt" from meaning "unregulated". Exempt works still have to comply with the building rules and can be inspected by the município (Art. 6.º n.º 8). And exempt works, apart from conservation works done only inside, must be notified to the câmara municipal no later than five days before they start, naming who will carry them out (Art. 6.º n.º 12 and Art. 80.º-A n.ºs 1 and 3). Listed buildings and their protection zones follow stricter rules.
The rules have changed twice recently, in January 2024 with Decreto-Lei n.º 10/2024 and on 1 October 2026 with Decreto-Lei n.º 108/2026, so the date of each work decides which version applied to it. That is a question for your lawyer, and another reason to ask the seller for dates.
What paper trail should the works have left?
Licensed works leave a licence file, comunicação prévia leaves a submission record the câmara can certify, and structural interior works leave a stability project and a signed technical declaration.
Each route leaves its own documents, and asking for them is how you test the seller's account of the works.
Licensed works leave the licence and the approved projects in the municipal file. Works under comunicação prévia leave the submitted communication, proof of the fees paid and the electronic receipt of submission; the person who made it can ask the câmara for a certidão identifying the operation and its submission date (Art. 35.º n.º 6). Exempt structural works inside the home leave the stability project and the termo de responsabilidade deposited with the start-of-works notice. Any project submitted to the câmara carries declarations by its authors that the applicable rules were observed (Art. 10.º).
Ask for the private paper too: the contractor's invoices and contract, the warranty on the works, the names of the engineer or architect involved, and photographs taken during the works. A seller who renovated carefully usually has them.
Missing paper is a question, not a verdict. In two pre-purchase inspections in 2026, the engineer recorded building work the documents did not show: a mezzanine in a property with a smaller approved area, and later alterations that the municipal record identified as unlicensed. Two cases are not a rate, and our inspections do not routinely review documents. They show why the documents and the building are worth reading side by side.
Since 1 October 2026, the professional who titles the sale records whether the seller presented a título urbanístico, declared holding one, or declared holding none (RJUE Art. 4.º-A n.º 14). That mention records a document or a declaration. Nobody compares the building with it. Our guide to what changed on 1 October 2026 covers the mechanism.
What does an inspection check in the renovated rooms?
An inspection records the physical evidence of each work: cracking, deflection, settlement, moisture around new wet areas, ventilation and visible installations, with photographs and stated limits.
An InspectOS Pre-Purchase Inspection treats the seller's list of works as a map. At each place where something changed, the engineer looks for how the building has responded: cracking at the corners of new openings, deflection in floors and ceilings where a wall was removed, settlement under an extension, moisture readings around a relocated bathroom or kitchen, ventilation in rooms created from former outdoor or storage space, and the visible state of new installations. Findings are recorded with photographs and their location, and the report says what could not be accessed.
When documents are supplied, the report can note where the layout on site differs from the plans the seller provided and list the questions that difference raises for your lawyer. It stops there. A non-invasive inspection does not open walls or ceilings, does not certify that works were licensed, and does not conclude that a work is illegal or can be regularised. Those are legal questions.
Where a finding needs more than a visual reading, for example cracking that may be active, the report says so and names the investigation that would answer it. Our guide to the property condition report shows how findings, limits and next steps are laid out. The report arrives within 48 hours of the site visit, once the required documents are received.
Who checks what before the CPCV?
Your lawyer reads the municipal and registry record of the works; the inspection records the physical facts; together they show whether the paper and the building describe the same property.
A renovation sits on both sides of due diligence. The lawyer establishes what was authorised and what the registry and the câmara record. The inspection establishes what is physically there and what condition it is in. Neither can do the other's job: a lawyer reading the municipal file cannot see the cracking under a new room, and an engineer on site cannot say whether a work was lawful. Our guide to the lawyer, the notary and the agent sets out who does what in a Portuguese purchase.
Inspect before signing a binding reservation or CPCV where possible. Findings can inform repair requests, pricing and contract terms. Your lawyer should advise on your rights and any inspection condition. Signing a contract can affect your options; it does not mean that every defect automatically becomes your sole legal responsibility.
Frequently Asked Questions
Did the seller need permission to remove an interior wall?
It depends on whether the wall played a part in the building's stability and on when the work was done. Under the RJUE in force since 1 October 2026, interior works that affect stability are exempt from licence and comunicação prévia only with a stability project and a signed termo de responsabilidade (Art. 6.º n.º 1 b)). Ask the seller for those documents, and ask your lawyer which rules applied at the date of the works.
Is a renovation without documents a reason to walk away?
Not on its own. Conservation and many interior works need no municipal procedure, so a missing licence can be normal. Missing paper for a structural change or an extension is a question for your lawyer, and the physical condition of that work is a question for an inspection. Together they tell you whether to proceed, renegotiate or walk away.
Can I rely on the seller's renovation photos?
They help you locate the works and date them, and they are worth asking for. They show what the contractor chose to photograph, at the moment it was taken. They do not show how the building has behaved since, which is what an inspection records.
What if problems from the works appear after I move in?
In an ordinary resale, a buyer has one year from discovering a hidden defect to report it and six months from that report to bring an action, within five years of delivery (Código Civil, Arts. 916.º and 917.º), and carries the burden of proof (Art. 342.º n.º 1). A dated inspection report from before the CPCV helps show what the building was like when you bought it.
Conclusion
A renovated home can be a good purchase, and buying it as it is can be a sound decision. Before you commit, list the works, ask for the paper each one should have left, have your lawyer read the record and have an engineer record the building. A Pre-Purchase Inspection costs a fraction of the sinal you commit at the CPCV, and it turns the seller's renovation story into findings you can act on.
→ Book a Pre-Purchase Inspection · get a quote at inspectos.pt/en/home-inspections
Updated October 2026 | InspectOS Portugal · Legal references last reviewed 15 October 2026
Sources: Decreto-Lei n.º 555/99, de 16 de dezembro (RJUE), consolidated with Decreto-Lei n.º 10/2024 and Decreto-Lei n.º 108/2026 and Declaração de Retificação n.º 29-A/2026: Articles 4.º, 4.º-A n.º 14, 6.º, 6.º-A, 10.º, 35.º n.º 6 and 80.º-A · Decreto-Lei n.º 10/2024, de 8 de janeiro · Código Civil, Articles 342.º, 916.º and 917.º · InspectOS technical inspection record, August 2026 (single case) · InspectOS pre-purchase inspection records, May and August 2026 (two cases)