Is that pool or extension legal? Check the planning status before you buy

That glazed terrace, the extra room above the garage or the pool that doesn't appear on the plans can become a serious problem if you buy without checking. Before you sign, verify the planning status.

The problem nobody mentions

On the Costa Blanca there are thousands of homes with extensions, enclosed terraces, pools or change-of-use works carried out without a licence or not matching the original project. Many have been like that for decades and their owners don't even know — or prefer not to mention it. But when ownership changes hands, the problem is inherited.

If you buy a home with illegal works, you become the responsible party. The town hall can demand demolition, regularisation (if possible) or impose fines. And if you later want to sell, the next buyer will ask you the same question.

Warning signs

Pay attention if you notice any of these situations:

• The actual floor area seems larger than the deed or cadastre states.
• There are rooms or structures that don't appear on the plans.
• There's a pool, covered porch or enclosed garage with no reference in the documentation.
• The seller avoids talking about permits or says "it's always been done this way here".
• The price is strikingly low for the area.

How to check it

A full verification means cross-referencing several sources:

1. Check the PGOU (the municipal general plan) to confirm what can and cannot be built on that plot.
2. Cadastral check — the cadastre record shows the registered built area. If it differs greatly from reality, there's a problem.
3. Land registry extract (nota simple) — to verify charges, encumbrances and the registry description.
4. On-site inspection — I compare what I see with what the documents say.

What the PGOU says

Each municipality has its own PGOU, which sets out for every plot: the maximum buildable area (how many m² you can build), the plot coverage (what percentage of the plot you can cover), the permitted heights, the setbacks (distance to boundaries), and the permitted uses. An extension that exceeds any of these parameters is, in principle, illegal.

On the Costa Blanca it's common to find homes on urban land with extensions exceeding the buildable area, or on non-developable land where more has been built than the rules allow.

Cadastre vs. registry

Many people confuse the two. The cadastre reflects the physical reality (built area, plot) and has tax implications. The land registry reflects the legal reality (who owns it, charges). They may not match. If the cadastre shows 120 m² and the actual home is 180 m², those extra 60 m² probably have no licence.

Consequences of buying something illegal

The most common:

• Planning enforcement proceedings: the town hall can order the demolition of what was built illegally.
• Inability to legalise: if the works don't comply with the current PGOU, they can't be regularised.
• Insurance problems: a claim affecting a non-legalised area may not be covered.
• Difficulty reselling: the next buyer (or their bank) will spot the problem.

What I can do for you

I offer two services that tackle this problem directly:

• Planning consultation — I analyse the PGOU regulations applicable to your plot and give you a written answer on what can and cannot be done.
• Pre-purchase survey — full inspection of the home: structure, installations, damp and the planning/registry situation. Four levels depending on depth; with a written report, from €395 + VAT. View Building survey →

Frequently asked questions