Illegal or unregistered building work on your home
You will know whether your home's irregular work can be fixed, how, and what it means for selling or mortgaging it.
Some Spanish homes have an extension, a pool or a conversion that was never licensed or registered. Others have a Catastro record and a Land Registry entry that do not match what is actually built. This topic helps you find out which applies to your home, whether it can be fixed, and what it means…
Pick the article that fits your situation
Finding the mismatch between the Catastro, the Land Registry and what is built
Compare your nota simple, your Catastro certificate and the real building to see which differences need action and which do not.
Selling or mortgaging a home with irregular work
You can sell a home with irregular work, but the notary warns the buyer, buyers push the price down, and banks often lend less or refuse.
About this topic
Key rules
- Time limit: The time limit for the council to restore planning legality is set by each region, and it runs from the completion of the works; in the Valencian Community it is 15 years, so check your own region.
- Catastro update: After work is registered or legalised, you declare it to the Catastro with form modelo 900D within two months.
Illegal or unregistered building work on your home: the whole process, step by step
- Get a nota simple and compare it with the Catastro and what is built. Read: Finding the mismatch between the Catastro, the Land Registry and what is built: First step, before you decide anything. Online copies arrive by email within one working day.
- Check whether the time limit for council action has run: Right after you find a mismatch.
- Choose between legalising the work and registering it as old.: Once you know the work's age and whether it fits the current planning rules, pick one route.
- Apply for a licence to legalise the work, if it fits the planning rules.: The council's notice sets your deadline, so apply within it.
- Answer a demolition order: send allegations, appeal to the council or go to court.: Only if the council opens a file. The decision notice sets each deadline, so act as soon as it arrives.
- Declare the work to the Catastro with modelo 900D.: Last filing step, after the licence or the deed.
- Sell or mortgage the home with the irregular work. Read: Selling or mortgaging a home with irregular work: Last step. You can also sell before fixing the work, usually at a lower price. Banks may lend less, or refuse, on a home outside planning rules.
Documents you may need
The home
- Licence
- Nota simple from the Registro de la Propiedad — Finding the mismatch between the Catastro, the Land Registry and what is built
Translations and legal papers
- Deed of declaration of obra nueva (the notarial deed that registers a new building or extension) signed before a notary — Selling or mortgaging a home with irregular work
Other documents
- Catastro certificación descriptiva y gráfica — Finding the mismatch between the Catastro, the Land Registry and what is built
- Council application form for legalisation
- A technical project or memoria técnica from an architect or technical architect
- Technician's certificate that the work meets planning rules
- Proof that you paid the council fee
- Architect's certificate of the project — Selling or mortgaging a home with irregular work
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Always verify important information with the relevant official authority or a qualified adviser before acting. This website uses large language models together with various public data sources, official government documents and other established sources. Due to the amount of data on this website, some information might be wrong. Information may also be incomplete or outdated.