In short. An installer's risk does not sit in the workshop: it sits in the third-party asset being worked on and in the installation being entered. The amounts required by the Spanish low-voltage regulation, the thermal installations regulation or the gas technical instructions authorise you to trade, but they do not measure that exposure. What decides an assembly claim is four sections of cover —property being worked upon, property in care, custody or control, completed operations and tenant's legal liability— together with the policy's temporal delimitation of cover, because a defective weld can manifest years after handover.
Manufacturing industry recorded an incidence rate of 4,321 workplace accidents with sick leave per 100,000 workers and construction one of 5,787, against a national average of 2,732.6, according to the INSST annual report on workplace accidents with 2024 data. These are the sectors an installer walks into, and these are the figures your industrial client has in front of them when they ask for the insurance certificate before letting you through access control.
Which is why the conversation never starts with your workshop. It starts with what you can break inside somebody else's plant.
The amounts the regulations require in order to trade
No Spanish rule imposes liability insurance on a self-employed worker as a general matter. What does exist are sector authorisation requirements: registering as an installation company in certain regulated activities requires evidence of a policy with a minimum amount. The framework is set by article 21.1 of Law 17/2009, which only allows compulsory insurance to be required by a rule having the rank of statute, where the activity presents a direct and specific risk, and with a guarantee proportionate to that risk.
These are the amounts in force in the most common assembly and installation activities:
| Activity | Rule | Minimum amount |
|---|---|---|
| Low-voltage installation company, basic category | REBT, ITC-BT-03 (as worded by RD 298/2021) | 600,000 € per claim |
| Low-voltage installation company, specialist category | ibid. | 900,000 € per claim |
| Thermal installation or maintenance company | RITE, article 37 c) | 300,000 € |
| Ibid. operating level 2 refrigeration circuits | RITE, article 37 f) (RD 178/2021) | 900,000 € |
| Gas installation company, categories A / B / C | ITC-ICG 09 (RD 298/2021) | 900,000 / 600,000 / 300,000 € |
| Tower cranes / self-propelled mobile cranes | MIE-AEM-2 / MIE-AEM-4 | 600,000 € / 1,000,000 € |
One point is frequently overlooked: these amounts are required of the registered installation company, not of the individual technician. A self-employed professional who registers as an installation company is caught by them; an employee holding a professional card and working for an installation company is not. We develop the point in whether a self-employed professional must hold liability insurance.
Is that limit enough to get into a plant?
No, and it is worth drawing a sharp line between two things the market confuses daily.
The regulatory limit is what authorises you to trade. It is set on a uniform basis for an entire activity, without regard to which installations you work in or what they are worth. It is an administrative floor.
The contractual limit is what your industrial client's specification will require. That one is sized by exposure: the value of the equipment you work on, the cost of replacing a damaged line, the business interruption of a production stoppage and the figure the group parent has set as its procurement standard. An authorised installer with 600,000 euros complies with the regulation and still cannot sign a framework agreement with a large account requiring several million.
The distance between those two numbers is not a pricing problem. It is a commercial access problem: you are out of the process before anyone looks at your technical offer.
Has an insurance certificate of yours been rejected for an insufficient limit? Let us review what the specification is asking for.
The four sections that decide an assembly claim
Before going in: none of the four is a statutory category. They are wording labels. No rule in the Spanish official gazette defines them, and two insurers can give the same name to covers of different scope. Which is why they must be read, not bought by name.
Property being worked upon. Covers damage to the client's asset on which you are performing the work. It is the section most needed in assembly work and the least often bought. And it carries an exclusion within the exclusion worth bearing in mind: even where bought, the part actually worked on is normally left out. The policy may respond for damage caused to the rest of the equipment, not for redoing the defective weld. We set it out in detail in property in care, custody or control and property being worked upon.
Property in care, custody or control. Covers the third-party asset in your possession by reason of the work: the equipment taken to the workshop for repair, the component handed to you for installation, the tool lent by the client. You need not be working on it; holding it in custody is enough.
Products and completed operations liability. Responds for damage that manifests after the work has been handed over, through a defect in execution. It is the installer's typical claim —and the one most often sub-limited or excluded outright. It should not be confused with public liability, which covers damage caused during the works: two different moments and two different sections.
Tenant's legal liability and cross liability. Tenant's legal liability operates where you work in third-party premises made available to you temporarily —a warehouse, a store, a laydown area— and responds for damage to that space. Cross liability comes into play where you work alongside other companies on the same site and several of them are named as insureds under a single policy: it allows one to claim against another without insured status blocking the cover.
In all four cases, the name and precise scope depend on the wording of each policy.
What is triggered in each scenario
| Claim scenario | Which section responds | What is left out |
|---|---|---|
| Welding work that starts a fire in the client's warehouse | Public liability: damage to third-party property other than the item worked on | The welded item itself, unless property being worked upon is bought; the client's business interruption if not agreed |
| A part falling during lifting onto the client's machinery | Public liability, or property in care, custody or control if the machine was in your custody | The dropped part itself; the damage if the lifting equipment required an authorisation that was not evidenced |
| A fault appearing six months after commissioning | Completed operations liability, if bought and the temporal delimitation reaches the claim | The cost of redoing the defective work; claims outside the agreed period of cover |
| Damage to the very equipment being installed | Property being worked upon, if bought | The part actually worked on, still excluded in most wordings |
| Injury to a client employee walking through the plant | Public liability, as damage to a third party | Injury to your own employee, which falls to the employers' liability section |
| Damage to the area of the warehouse lent as a temporary workshop | Tenant's legal liability | Fair wear and tear; third-party contents stored there, unless agreed |
A note if you have employees: injury to your own employee does not go through public liability but through the employers' liability section, and there is one front no policy can assume. Article 164.2 of the Spanish General Social Security Act places the benefits surcharge directly on the infringing employer and renders void as a matter of law any agreement to cover it. It is a statutory nullity, not a negotiable exclusion: we explain it in why the benefits surcharge cannot be insured.
Do you know whether your policy protects the asset you are working on or only what is around it? Request a technical reading of your wording.
Damage that surfaces years later
This is the worst-covered exposure in the sector, and it has nothing to do with the limit and everything to do with time.
In assembly work, a defect in a weld, a torque setting or an insulation can take years to manifest. The claim arrives long after the work was accepted, and by then the question is not what cover that year's policy carried, but which policy responds today.
Where the contract is written on a claims made basis, cover is conditional on the claim arriving during the period of insurance. Article 73, second paragraph, of the Spanish Insurance Contract Act (Law 50/1980) admits two modalities: subsequent cover, which requires a period of not less than one year from the termination of the contract, and the retrospective modality, which requires cover to be extended to events occurring at least one year earlier. The provision itself classifies them as limitative clauses, subject to the formalities of article 3, and the Spanish Supreme Court, in its Full Court judgment 252/2018 of 26 April, clarified that they are two distinct clauses whose requirements are not cumulative.
One year is the statutory floor, not the term. And there lies the operational trap: an installer who switches insurer and buys a policy without a sufficient retroactive date leaves all earlier work uncovered, even though the insurance was never interrupted. We develop it in claims made versus occurrence.
When the work forms part of a building project
If your installation is incorporated into a building project, the framework of time limits changes. Article 17.1 of the Spanish Building Regulation Act (Law 38/1999) sets three liability regimes: ten years for damage affecting structural elements, three years for damage affecting habitability and one year for defects in execution affecting finishing elements, the last of which the provision attributes specifically to the builder. Article 18 adds that actions become time-barred two years after the damage occurs.
One frequent confusion is worth undoing here. The ten-year structural warranty under article 19 binds the developer, not the installer: it is the developer who must take it out. What happens in practice is that developer and main contractor pass the requirement down to the installer by contract, through indemnity clauses, retentions or insurance requirements in the specification. The obligation does not arise from the statute for you; it arises from the contract you sign. We deal with it in ten-year structural liability.
To understand what moves the price of that cover, see what sits inside a liability premium; and for the fit by activity, our solutions by sector.
The role of an independent broker
Two policies with the same premium and the same main limit can leave an installer in opposite positions, depending on whether they include property being worked upon, how completed operations is worded and how far the retroactive date reaches. As an independent brokerage registered with the Spanish DGSFP under reference J0140, we act on the client's mandate: we negotiate the wording before the price, we compare drafting across the whole market and, when a claim arises, we defend the insured before the insurer.
In assembly and installation there is also a preliminary task that is rarely done: reading the industrial client's specification before placing the policy, so that the certificate the insurer issues says exactly what the specification requires. You can see the full scope of the line on our liability cover page.
Frequently asked questions
What liability insurance does an installer need? A general liability policy with a public liability section is the starting point, but the decisive covers are those protecting the third-party asset and the damage arising after handover: property being worked upon, property in care, custody or control, completed operations and tenant's legal liability. If you act as a registered installation company, you must also evidence the minimum amount in your sector regulation.
Is the insurance required by the regulations enough? It satisfies the rule, but it does not measure your exposure. Those amounts are an administrative authorisation requirement. The limit you need is sized by the value of the installation you enter and by what your client's specification requires.
Does the policy cover damage to the machine being installed? Usually not under public liability, which does not insure the correct performance of the contracted service. It requires a property being worked upon section and, even then, the part actually worked on is normally excluded.
What happens if the failure appears two years after handover? It depends on holding completed operations cover and on the temporal delimitation reaching the claim. In claims made policies, the statute requires at least one year of retroactive date or of subsequent cover depending on the modality: a floor, not the term.
Does an installer need ten-year structural warranty cover? Not as a duty of its own: article 19 of Law 38/1999 imposes it on the developer. It is another matter that developer and main contractor pass the requirement down by contract, which happens frequently.
Sources and legislation
- Law 50/1980, the Spanish Insurance Contract Act, articles 3 (limitative clauses) and 73, second paragraph (temporal delimitation of cover).
- Law 38/1999, the Spanish Building Regulation Act, articles 17.1, 18 and 19.
- Royal Legislative Decree 8/2015, consolidated text of the General Social Security Act, article 164.2 (uninsurability of the benefits surcharge).
- Law 17/2009 on free access to service activities, article 21.1.
- Spanish low-voltage electrotechnical regulation, ITC-BT-03, as worded by Royal Decree 298/2021.
- Regulation on Thermal Installations in Buildings, article 37, paragraphs c) and f), the latter as worded by Royal Decree 178/2021.
- ITC-ICG 09 of the technical regulation on the distribution and use of gaseous fuels, as worded by Royal Decree 298/2021.
- Complementary technical instructions MIE-AEM-2 and MIE-AEM-4 of the regulation on lifting and handling equipment.
- Spanish Supreme Court (First Chamber, Full Court) judgment 252/2018 of 26 April, on the two modalities of article 73, second paragraph, of Law 50/1980.
- Spanish Supreme Court (First Chamber) judgment 730/2018 of 20 December, on the scope of public liability insurance.
- INSST, annual report on workplace accidents, 2024 data.
This information is for guidance only and does not constitute binding advice. Cover, limits and exclusions are governed in all cases by the particular conditions of each policy. New Brokers Correduría de Seguros, S.L., registered with the Spanish DGSFP under reference J0140.
