Illegal Building Work in Greece: How Foreign Buyers Can Avoid Permit Problems
A Greek engineer should compare permits, plans, floor area, regularisation records, and building identity before a foreign buyer signs.
The risk
Foreign buyers often focus on title. They also need to check the building. In Greece, older homes may have terraces, rooms, basements, pools, pergolas, or extensions that do not match the permit file.
Some issues can be regularised. Some cannot. Some are cheap. Some change the whole value of the property.
What the engineer should check
- Building permit and approved plans.
- Actual floor area compared with the legal plans.
- Semi-outdoor spaces, terraces, basements, and storage areas.
- Pool, pergola, boundary wall, and parking permits.
- Energy certificate.
- Electronic building identity, where required.
- Any regularisation certificates for past illegal works.
- Whether future renovation is allowed.
Why square metres can mislead
Listings often show a single size. That number may include legal indoor space, regularised space, storage, terraces, or informal additions. Ask your engineer to split the area into legal categories.
This matters for price, tax, insurance, rental use, future sale, and bank valuation.
Red flags
Be careful if a room is described as storage but used as a bedroom, if a basement has been turned into living space, or if a roof terrace has been enclosed. Also check pools, pergolas, boundary walls, and parking spaces.
These issues are common in many markets, not only Greece. The answer is not panic. The answer is a written engineer report before you sign.
Practical buyer tip
Add an engineer condition to your offer. The condition should say that the deal depends on a satisfactory technical review. If the seller refuses, treat that as a warning sign.
Do not buy first and "sort it out later" unless your lawyer and engineer have confirmed the cost, route, and risk in writing.
Useful next read: Greek Property Due Diligence Checklist for Overseas Buyers.
Use official tax and registry portals such as AADE and the Hellenic Cadastre alongside local professional advice.
Why this issue matters so much to foreign buyers
An unauthorised alteration can be easy to miss when the property looks finished and has been occupied for years.
A room may have been enclosed, a basement converted, a terrace roofed, a pool added or a storage area changed without the buyer understanding how it appears in the legal building file.
The safe question is not "has it been here a long time?" It is "what does the engineer's evidence show?"
Engineer review
The engineer should compare documents with reality
Ask the engineer to inspect the property and compare it with the permits, approved plans and recorded areas available for the building.
The goal is to identify discrepancies before the buyer owns them.
Gov.gr confirms that authorised engineers can register and manage property details in the Electronic Building Identity system and issue a completeness certificate after the process is final, inspection has occurred and the required fee has been paid.
Common examples to investigate
Potential issues can include enclosed balconies, extensions, roofed terraces, pools, pergolas, converted basements, changed storage areas, altered internal layouts and changes of use.
Not every difference has the same legal importance or solution.
The buyer should not decide whether an alteration is acceptable from appearance or age. Ask the engineer to explain its documented status.
Do not confuse title with building compliance
A lawyer can establish that the seller owns the property while an engineer finds that parts of the building do not match the approved file.
That is why Greek Property Title Checks and technical due diligence are separate parts of the purchase.
"It can be regularised" needs evidence
If the seller or agent says an issue can be regularised, ask your independent engineer and lawyer what that means for this exact property.
You need to know what procedure is available, who is responsible for completing it, what evidence will exist afterward and whether completion of the sale should wait until the work is documented.
Do not inherit a technical problem merely because somebody promises it is routine.
Renovation plans may expose old problems
A buyer planning major renovation can discover that the existing building file and the structure on site do not align.
That can affect design, permits, budget and schedule.
Before buying a renovation property, ask the engineer or architect to distinguish between work needed to make the existing building file usable and the approvals needed for your future project.
The \1 covers this in more detail.
Newer property is not automatically risk-free
A recently built home can still have specification differences, alterations or incomplete documentation.
For an off-plan or new-build purchase, compare the contracted property and approved plans with what is actually delivered.
Read New Build vs Resale Property in Greece before assuming new means no due diligence.
Apartment buyers should inspect shared issues
An apartment's interior may be compliant while the wider building has problems.
Ask about common areas, roof structures, enclosed shared spaces, lifts, façade work and any known building-wide regularisation or permit issues.
The cost and practical impact can affect all owners.
Rural and island properties require practical checks
Island and village homes can have older additions, external kitchens, stores, cisterns, retaining walls, pools and terraces.
Access for engineers and contractors can also make corrective work more expensive.
If you are buying from abroad, request photographs and written findings so the issue can be reviewed before you travel to sign.
Price the problem before you accept it
Some technical issues are capable of resolution and may become part of the negotiation.
But the buyer should know the expected professional work, cost, timing and effect on future renovation or resale.
An unknown issue is not a discount. It is uncertainty.
A useful pre-deposit checklist
Before paying a non-refundable amount, ask:
- Has an independent engineer inspected the property?
- Do the plans match the physical building?
- Are floor area and use consistent with the file?
- Are later additions documented?
- Is the Electronic Building Identity position understood?
- Must the seller complete anything before the deed?
- Does the issue affect the renovation or rental plan?
Combine this with the full due-diligence checklist.
Sources reviewed
Official technical-process references include Gov.gr services for the Electronic Building Identity register and completeness certificate, administered by the Technical Chamber of Greece. The legal significance and available remedy for an alteration are property-specific and should be confirmed by the buyer's engineer and lawyer.
