Seguro Decenal: Spain’s Ten-Year Structural Insurance Explained
If you are building a villa, buying off-plan or selling a Spanish home under ten years old, one policy can decide whether the deal completes: the seguro decenal. Here is what the ten-year structural guarantee actually covers, who must hold it, the self-build exemption almost everyone misquotes — and what happens at the notary when it is missing.
Anyone who builds, buys or sells a newer home in Spain eventually collides with the seguro decenal — the ten-year structural damage insurance created by the Ley de Ordenación de la Edificación (LOE, the 1999 Building Act). It decides whether a new villa can be registered, whether a new-build buyer is protected against structural failure, and whether a self-built house can change hands before its tenth birthday. It is also one of the most misquoted rules in Spanish property. This guide sets out what the decenal covers, who must hold it, what it costs — and the exemption that changes everything for self-builders.
The short version
- The decenal is damage insurance on the building, not liability cover. It pays the owner for structural damage — foundations, beams, slabs, load-bearing walls — for ten years from the acta de recepción, the formal acceptance of the works.
- It is compulsory only for buildings whose principal use is housing, where the building licence was applied for on or after 6 May 2000. The promotor (developer) takes it out.
- Cover follows the building: successive buyers are insured automatically by law, with nothing to endorse.
- The enforcement chokepoint is article 20 LOE: notaries will not authorise, and registrars will not register, the new-build deed without evidence of the guarantee.
- The individual self-builder of a single own-use home is exempt — but selling within ten years revives the obligation unless the buyer expressly waives it in the deed.
- Insurers demand an OCT (independent technical control body) appointed before works start. A retroactive decenal on a finished building is difficult and costs more.
- Budget roughly 0.5%–1.5% of the build budget as a single premium, plus OCT fees — market figures, always subject to the OCT report.
What the seguro decenal is — and what it is not
The seguro decenal (ten-year building damage insurance), also marketed as garantía decenal, is a first-party damage policy on the building itself. It compensates the owner for material damage caused by structural defects — in the words of article 17.1.a LOE, defects affecting the foundations, supports, beams, floor slabs, load-bearing walls or other structural elements that directly compromise the building’s mechanical resistance and stability.
Three things it is not. It is not liability insurance for the builder or architect: it pays you without you proving anyone was at fault, and article 19.3.c LOE expressly stops the insurer using defences it may hold against the developer. It is not home insurance: a multirriesgo hogar (multi-risk home policy) covers fortuitous events, and standard policies exclude construction defects and vicios ocultos (hidden defects) — that boundary is mapped in our guide to home insurance in Spain. And it is not a builder’s warranty: the policy survives the builder’s disappearance or bankruptcy.
Legally the guarantee can take three forms under article 19.1.c LOE: a damage insurance policy, a surety bond (seguro de caución) or a financial guarantee. In practice the damage policy is the market norm, which is why everyone simply says “the decenal”.
The LOE liability ladder: one, three and ten years
The LOE makes the people who create a building answer for defects on a sliding scale, all counted from the same start date. Article 17 sets three tiers, and understanding which tier your problem sits in is half the battle in any dispute over a Spanish new build.
| Period | Defects covered | Who answers |
|---|---|---|
| 1 year | Finishing and snagging defects — elementos de terminación o acabado | The constructor alone (art. 17.1.b, closing rule) |
| 3 years | Defects in constructive elements or installations breaching the habitability requirements of art. 3.1.c LOE | The building agents; insurance for this tier was never made compulsory |
| 10 years | Structural defects compromising the building’s mechanical resistance and stability | The building agents — and the only tier with compulsory insurance: the decenal |
Only the ten-year structural tier ever became compulsory to insure, and only for housing. The LOE’s second additional provision envisaged extending the obligation to the one- and three-year guarantees by Royal Decree — a decree that, more than a quarter of a century later, has still not been issued. So the decenal insures the structural tier alone. Habitability defects, damp among them, sit in the three-year tier and are uninsured unless optional cover was bought.
Every clock runs from the acta de recepción — the formal acceptance of the works, signed without reservations or dated from when any reservations were put right. Not from your purchase date, and not from the certificado final de obra (the architects’ completion certificate). Under article 6 LOE, reception must take place within thirty days of notified completion, and it is deemed tacitly produced if the developer says nothing in writing within those thirty days.
One further clock matters. Article 18.1 LOE gives you two years to sue from the moment the damage occurs. Structural damage appearing in year nine is still covered — but it must be pursued promptly.
Who must take it out, and when the clock starts
The promotor is the policyholder for the ten-year guarantee, under article 19.2.a LOE; for the one-year finishing guarantee, where contracted, the policyholder is the constructor. The insured parties are the developer and “the successive acquirers of the building or part of it”. Cover attaches to the building, not the person: every later owner is insured automatically, with no endorsement, no consent and no extra premium.
The obligation bites on buildings whose principal use is housing, where the building licence was applied for on or after 6 May 2000 — six months after the LOE reached the official gazette. Offices, hotels and warehouses can buy a decenal voluntarily, but the law does not force them to. Where the decenal sits among Spain’s genuinely compulsory covers is set out in our guide to which insurance is required by law in Spain.
The premium is normally a one-off single payment, and article 19.2.b LOE requires it to be paid by the moment of reception of the works. The same article allows agreed instalment plans — and, importantly, non-payment of a later instalment does not entitle the insurer to cancel the guarantee. Skipping the obligation is not a loophole either: under article 19.7, whoever should have arranged the guarantee answers personally for the damage it would have covered.
The article 20 block: no decenal, no registered deed
The LOE did not create an inspector who checks policies. It created something far more effective: article 20.1 orders that notaries shall not authorise, and land registrars shall not register, deeds of new-build declaration (escrituras de declaración de obra nueva) for LOE buildings unless the article 19 guarantee is evidenced before them.
That single article is why the decenal cannot simply be ignored. Without it, the finished house cannot be declared and inscribed at the Land Registry as a completed building. In practice an unregistered or half-registered property is very hard to mortgage and very hard to sell, because the buyer’s lawyer and the buyer’s bank will both find the gap in the nota simple within minutes.
The autopromotor exemption — and the resale trap
Here is the rule that half the internet states backwards. Under the LOE’s second additional provision, the decenal is not exigible from the individual autopromotor (self-builder) of a single family dwelling for their own use. If you buy a plot near Javea and commission a villa to live in yourself, the law does not force you to buy a decenal. Registrar doctrine reads the conditions cumulatively: an individual, one single dwelling, genuinely for own use, genuinely self-promoted.
The exemption comes with a sting in its tail. If you sell the house within the ten-year period, the same provision obliges you, “salvo pacto en contrario” (unless agreed otherwise), to contract the guarantee for the time remaining. The notary and registrar will block the sale deed unless either the guarantee is produced or the buyer expressly exonerates you in the deed itself — and you must positively accredit that you actually used the dwelling. Registrar doctrine (DGRN, today the DGSJFP) polices both requirements, and re-examines the point on each successive sale within the decade.
On paper, then, the waiver looks like an easy exit. In practice it often is not. A buyer who signs the exoneración is giving up the insurance route entirely for any structural failure in the years remaining — and, in practice, a buyer’s bank can refuse to lend on a sub-ten-year home without a decenal even where the buyer would happily sign. Valuers (tasadores) routinely check for the policy on newer builds. These are market behaviours rather than legal rules, but they decide real transactions. Confirm the position with your lawyer before signing anything.
The OCT and the geotechnical study
No insurer writes a decenal blind. The market’s answer is the OCT — Organismo de Control Técnico (independent technical control body) — an engineering firm the developer engages, whose reports the insurer relies on. Worth being precise: the OCT is a requirement of the insurance market, not of the LOE. The Act never mentions it. But in practice you will not get a policy without one.
The OCT’s work starts before the first shovel of earth: it reviews the geotechnical study of the plot and the structural design at project phase, then inspects the foundations and structure as they are built, issuing a sequence of reports (the D0–D6 series) that track the risk from soil survey to completion. That timeline is exactly why a decenal is easy at the start of a project and hard at the end of one.
Retroactive cover on a finished building — obra terminada — does exist with some insurers, but it needs a full retrospective survey with additional testing and trials on the finished structure, which can include opening up parts of the building. It costs more, takes longer, and most insurers refuse it where no OCT supervised the build; MAPFRE’s own material describes no-OCT issuance as exceptional and conditional.
What a seguro decenal costs
There is no official tariff, so treat everything below as market figures, not statistics — and always subject to the OCT report on your particular plot and structure. Specialist brokers and OCT firms typically quote around 0.5%–1.5% of the material execution budget (the PEM), with minimum premiums around €2,000–2,200. One published worked example came out near 1.1%, roughly €10 per square metre.
| Item | Typical figure | Notes |
|---|---|---|
| Decenal premium | ~0.5%–1.5% of the PEM | Single premium, payable by reception; minimums around €2,000–2,200 |
| OCT fee, single-family home | ~€1,300–3,000 | Depends on floor area, complexity and number of site visits |
| Retroactive (obra terminada) | Indicative €1,600–2,500 plus the survey | One specialist broker’s figures; more for blocks and rehabilitation |
| Illustrative all-in, €300k self-build | ~€4,000–7,500 | OCT plus premium; an illustrative estimate, not a quote |
Two budgeting notes. First, the premium is priced on the build cost, not the plot or market value — land does not enter the calculation. Second, the OCT fee is payable whether or not a policy is ultimately issued, which is one more reason to line up insurer and OCT together at project stage rather than sequentially.
Cover, sum insured, franchise and exclusions
The LOE fixes the floor of the cover, and the market builds on it. The minimum sum insured for the decenal is 100% of the final cost of the material execution of the works, professional fees included — article 19.5.c. Any excess (franquicia) on the ten-year guarantee may not exceed 1% of the insured capital of each registered unit (article 19.8). When damage occurs, article 19.6 lets the insurer choose between paying the assessed loss in cash or repairing it.
Exclusions are largely standardised by article 19.9 LOE. Policies may exclude bodily injury and economic loss beyond the material damage itself, damage to neighbouring or adjacent buildings, movable property inside the building, damage caused by modifications made after reception, misuse or lack of maintenance, fire, caso fortuito and force majeure, and defects that were noted with reservations at reception and never remedied. In short: the decenal rebuilds a failing structure; everything around that event belongs to other policies.
The optional trienal and other add-ons
The three-year habitability guarantee — the trienal — exists in the LOE but was never made compulsory and is rarely contracted on its own. In the market it usually appears as optional add-ons to decenal policies. Generali’s own Garantía Decenal, for example, lists optional covers including three-year roof waterproofing (first year excluded), facade and basement waterproofing, damage to pre-existing structures, revaluation of capital and deductibles, waiver of subrogation and three-year stability of non-load-bearing facade elements. Useful options on a quality build — but options, not defaults.
Remember the boundary on the other side too. From the day you move in, fire, water leaks, theft and liability are the territory of your multirriesgo hogar, which needs arranging separately from all of this — our expat guide to home insurance in Spain walks through that policy line by line, and holiday-home owners have their own version in our overseas holiday home insurance page. The decenal never replaces either.
Claims and time limits
A decenal claim is a first-party damage claim, and that is its quiet superpower. You do not sue the architect, prove negligence or wait for experts to apportion blame between builder and engineer. You notify the insurer of structural damage, and article 19.3.c stops it hiding behind defences it may have against the developer. The insurer then repairs or indemnifies, and argues with the responsible parties afterwards.
The time limits stack like this. The damage must manifest within the ten-year window counted from the acta de recepción. From the moment it occurs, article 18.1 LOE gives two years to enforce liability, and the two-year prescription for damage-insurance contract actions under article 23 of Ley 50/1980 points the same way. Notify fast in any case: article 16 of Ley 50/1980 sets a default of seven days from learning of the loss, unless the policy allows longer.
Once notified, the general machinery of Spanish insurance law applies: the insurer must pay the undisputed minimum within 40 days, with penalty interest for unjustified delay, under articles 18 and 20 of Ley 50/1980. Document everything — cracks photographed with dates, a technical report if you can get one, and the acta de recepción to anchor the timeline.
Buying or selling a home under ten years old
If you are buying a Spanish property completed within the last decade — resale or brand new — the decenal should be on your lawyer’s checklist, because by law you become an insured person the day you complete. Here is what to ask for.
- The nota simple and the escritura de obra nueva. The registered new-build deed must evidence the guarantee (article 20.1), so the registry paperwork is your first tell. No guarantee mentioned on a post-2000 dwelling is a question that needs answering — autopromotor exemption, or a problem.
- The policy itself. Insurer, sum insured, franchise, and any optional covers. As a successive acquirer you are insured automatically (article 19.2.a) — but you want to know what you are inheriting.
- The acta de recepción. It fixes the start of the ten years, so it tells you exactly how much cover remains.
- The OCT final report. It shows the structure was independently supervised — and it is the document any future insurer or buyer will ask you for in turn.
- On an autopromotor resale: expect either a policy for the remaining period or a request that you sign the express waiver in the deed. Take advice before waiving — and check your own bank’s position first.
Two adjacent regimes are worth separating. Buying off-plan, your stage payments are protected by a different guarantee entirely — the insurance or bank guarantee for cantidades a cuenta (advance payments) under the LOE’s first additional provision, as amended by Ley 20/2015. And in an apartment block, the structure the decenal protects is the same structure your community of owners insures day to day — two policies, two different jobs. The wider purchase process is covered in our expat guide to insurance in Spain.
Extensions and major renovations
The LOE does not stop at new buildings. Article 2.2.b applies it to works on existing buildings that alter their configuración arquitectónica — total interventions, or partial ones producing an essential variation of the general exterior composition, the volumetry or the overall structural system, or which change the building’s characteristic use. On housing, such works can trigger a decenal for the new work.
Registrar doctrine (DGRN, today DGSJFP) has required the guarantee for extensions to dwellings — a 2005 resolution is the reference point — while a 2016 resolution accepted that a change of use without structural alteration does not trigger it. The practical line: knocking a wall through or retiling a bathroom is nowhere near the LOE; adding a floor, extending the footprint or replacing the structure very possibly is. If your project touches structure, raise the decenal question with your architect and lawyer before the licence application, not after.
For the professionals involved, this is a different insurance conversation altogether: builders and trades carry their own liability cover, which we deal with separately in our pages on constructors’ liability insurance in Spain, tradesman insurance and public liability insurance in Spain. Liability policies answer for what a person did; the decenal pays for what a building does. The two meet only at the point where the insurer, having paid you, chases whoever caused the defect.
Can Turner arrange a seguro decenal?
Sometimes — and we will tell you straight either way. Generali markets a Garantía Decenal through its business lines, aimed mainly at developer companies, and as Generali’s exclusive agent in Javea we can put your project to them. Individual self-build risks are underwritten case by case on the OCT report, and if yours is not one Generali will write, we will say so and point you to the specialist decenal market rather than waste your time. Send us the project details, the build budget and the OCT position, and we will give you an honest answer.
Ask us about decenal cover → Home insurance in SpainFrequently asked questions
The seguro decenal is ten-year damage insurance on a building’s structure, created by Spain’s 1999 Building Act (LOE). It pays the owner for material damage from defects in the foundations, supports, beams, floor slabs, load-bearing walls or other structural elements that directly compromise the building’s mechanical resistance and stability. It is first-party cover: you claim without proving anyone’s fault, and cover transfers automatically to every later owner. It is compulsory for buildings whose principal use is housing, where the building licence was applied for on or after 6 May 2000, and it runs for ten years from the formal acceptance of the works.
No — by law it is not exigible from the individual autopromotor of a single family dwelling built for their own use, under the LOE’s second additional provision. The conditions are read cumulatively: one individual, one dwelling, genuine own use, genuine self-promotion. But the exemption revives if you sell within ten years, when you must insure the remaining period unless the buyer expressly waives it in the deed. And in practice, banks financing a self-build mortgage often require the decenal anyway, so many self-builders take it voluntarily. Decide at project stage, because a retroactive policy is far harder to obtain.
Only through the waiver route. A self-builder selling within the ten-year period must either contract the guarantee for the time remaining or be expressly exonerated by the buyer in the sale deed itself, and must positively prove they actually used the dwelling — registrar doctrine checks both. Without one of the two, the notary and registrar will block the transfer. Be aware that a buyer who signs the waiver gives up the insurance route for any structural failure, and a buyer’s bank can refuse to lend on the property, so waivers sink deals in practice. Take legal advice before relying on one.
Specialist brokers and OCT firms typically quote around 0.5% to 1.5% of the material execution budget as a one-off single premium, with minimum premiums around 2,000 to 2,200 euros; one published worked example came out near 1.1%, roughly 10 euros per square metre. Add the OCT fee, typically 1,300 to 3,000 euros for a single-family home depending on size and complexity. For a 300,000 euro self-build, OCT plus premium commonly lands around 4,000 to 7,500 euros all-in. These are market figures, not official statistics, and every quote depends on the OCT’s assessment of the plot and structure.
Material damage to the building caused by structural defects — foundations, supports, beams, floor slabs, load-bearing walls and other structural elements — where the defect directly compromises mechanical resistance and stability. The minimum sum insured is 100% of the final material execution cost of the works, professional fees included, and any excess is capped at 1% of the insured capital per registered unit. It does not cover habitability defects such as damp (the three-year tier), finishing defects (the one-year tier), contents, damage to neighbouring buildings, post-completion alterations, poor maintenance or fire. The insurer chooses between paying the assessed damage or repairing it.
It is possible with some insurers but genuinely difficult. Because no OCT supervised the build, the insurer needs a full retrospective survey of the finished structure, with additional testing and trials that can include opening up parts of the building. Many insurers simply refuse; MAPFRE’s own material describes issuing without an OCT as exceptional and conditional. Where retroactive cover is offered, one specialist broker publishes indicative premiums of 1,600 to 2,500 euros for a single-family home before survey costs, and more for blocks or rehabilitation. If there is any chance you will need a decenal, arrange the OCT before works start.
Yes, automatically. Article 19.2.a LOE names the insured as the developer and the successive acquirers of the building or any part of it, so cover follows the property to each new owner for whatever remains of the ten years — no endorsement, no consent from the insurer and no extra premium. What you should do at purchase is documentary: get the policy itself, the OCT final report and the acta de recepción, because the acta fixes the start date and therefore exactly how many years of cover you are inheriting. Your lawyer can confirm the guarantee through the registered new-build deed.
Sometimes. The LOE applies to works on existing buildings that alter their architectural configuration — an essential variation of the exterior composition, the volumetry or the overall structural system, or a change of the building’s characteristic use. On housing, registrar doctrine has required a decenal for extensions, while accepting that a change of use without structural alteration does not trigger one. Ordinary refurbishment — kitchens, bathrooms, tiling — is nowhere near the threshold. If your project adds floors, extends the footprint or touches the structure, ask your architect and lawyer about the decenal before applying for the licence.
Sources & references: Ley 38/1999 de Ordenación de la Edificación (LOE), consolidated BOE text — arts. 2, 6, 17, 18, 19, 20 and the additional provisions; Ley 50/1980 de Contrato de Seguro (arts. 16, 18, 20, 23); Generali España — Garantía Decenal (product scope and optional covers); MAPFRE — Seguro Decenal (single-premium structure, OCT practice); Notarios y Registradores (compilation of DGRN/DGSJFP registrar doctrine on the autopromotor exemption and obra nueva); Decenalia (OCT process and obra terminada practice).
Premium and OCT figures are market indications compiled in August 2026, not official statistics, and every risk is priced individually on the OCT report. Registrar-doctrine points reflect published DGRN/DGSJFP practice and can turn on the facts of each case — confirm the position on your own purchase, sale or build with your lawyer before signing. This guide is general information, not legal advice.