New, mandatory rules on construction defects have been in force in Switzerland since 1 January 2026. Longer notice periods, an unwaivable right to rectification and a limitation period that can no longer be shortened will strengthen builders and property buyers. Companies in the construction and property sector need to review their sample contracts now, otherwise there is a risk of ineffective clauses and liability risks.
By resolution dated 30 April 2025, the Federal Council set the entry into force of the amendments to the Code of Obligations (CO) adopted by Parliament on 20 December 2024 for 1 January 2026. The referendum deadline expired unused on 19 April 2025.
The revision affects key provisions of the law on sales and contracts for work and services and aims to strengthen the legal position of builders and property buyers in the event of construction defects. Systematically, the revision is noteworthy because it introduces mandatory law in certain areas of a contract that has traditionally been strongly dispositive. While warranty law in sales and work contract law was previously largely left to private autonomy, the legislator is now setting binding minimum standards.
After several years of political discussions, the legislator is now creating more legal certainty – in particular through mandatory minimum standards for notice periods, rights to rectification and limitation periods. This article explains the most important changes, analyses their scope and shows the practical consequences for construction companies, project developers, investors, architects and legal counsel.
Aim of the revision: strengthening the client
The reform centres on improving the enforceability of defect rights. Practice has shown that short contractual notice periods or the exclusion of free rectification weaken the legal position of builders and property buyers. Careful inspection is often time-consuming, especially in complex construction projects, and hidden defects are often only discovered weeks or months later.
Legally, the notification of defects is still not a limitation period, but an obligation. Failure to do so does not lead to the forfeiture of the limitation period claim, but to the forfeiture of warranty rights. The extension to 60 days therefore does not postpone the start of the limitation period, but extends the period within which the authorised party must protect their rights. The distribution of the burden of proof also remains unchanged: the customer or buyer must prove the existence of a defect, its timely notification and the resulting damage. The revision therefore does not facilitate the substantive enforcement of claims, but primarily improves the formal protection of rights.
The extension of the notice periods to 60 days, the mandatory nature of the right to rectification and the unalterability of the five-year limitation period are intended to create an appropriate balance between the interests of the building contractor and those of the client. The reform thus strengthens legal certainty and reduces the risk of claims being lost solely due to formally short deadlines.
The most important legal changes at a glance
Standardised 60-day notice period (Art. 201 para. 4, Art. 219a para. 1, Art. 367 para. 1bis, Art. 370 para. 4 CO)
The new provisions stipulate that the deadline for notifying defects in the purchase of land and immovable property is now 60 days. This applies both to obvious defects from delivery or acceptance and to hidden defects from their discovery. The agreement of shorter deadlines is expressly invalid. The regulation also covers defects in movable works that were integrated into an immovable work as intended, as well as planning services by architects and engineers, insofar as these were the basis for the construction of the building. This systematically standardises the notice period and extends it to adjacent areas of performance.
In the case of obvious defects, the period begins with the objectively reasonable inspection after delivery or acceptance. In the case of hidden defects, the time of actual discovery is to be taken as a basis, whereby case law will presumably continue to be based on an objectivised concept of discovery. The 60-day period relates exclusively to the obligation to notify. It does not replace the warranty or limitation periods, but is effective within the respective warranty period. The mere abstract possibility of knowledge is therefore not sufficient, but a concrete indication of the existence of a defect is required.
In construction practice, SIA standard 118 (General Conditions for Construction Work) is often agreed. To date, this has provided for differentiated notice and warranty periods. The guarantee periods provided for in SIA standard 118 – in particular the two-year guarantee period for recognisable defects and the five-year period for hidden defects – remain in place. The new 60-day notification period does not replace these deadlines, but relates to the obligation to notify within the respective warranty or limitation period. However, if the SIA standard provides for shorter notification periods or restricts the mandatory right to rectification, the mandatory provisions of the Swiss Code of Obligations take precedence. The SIA standard is thus partially overridden. As the SIA standard is regularly agreed as general terms and conditions, it is also subject to GTC control. Provisions that fall short of mandatory CO law are not only ineffective, but can also be problematic from the point of view of unfair competition law. Contracting parties must therefore check whether existing standard contracts and references to the SIA standard need to be adapted.
It also remains unclear how courts will deal with staggered acceptances or partial acceptances in future. Decisions here will probably continue to be differentiated according to the functional independence of the parts of the work.
- Inalienable right to rectification free of charge (Art. 368 para. 2bis CO)
The new provision on the right to rectification free of charge is of particular significance. An agreement made in advance, according to which the right to free rectification is restricted or excluded, will in future be invalid if the defect relates to a building. This makes the right to rectification a mandatory core component of warranty law in the construction industry. Dogmatically, the right to choose between rectification, reduction and cancellation remains. However, the possibility of contractually excluding rectification in advance has been removed. Only after the defect has occurred can the parties continue to reach a different agreement. Contractual clauses that relativise this right no longer stand up to legal scrutiny.
It should also be noted that the right to rectification is still subject to the proviso of proportionality. If the improvement is technically impossible or involves disproportionate costs, it can be refused. The revision does not change this restriction.
- Extension of the right to rectification to certain property purchases (Art. 219a para. 2 CO)
The legal position of purchasers of properties with new buildings is also significantly extended. If someone acquires a plot of land with a building that is yet to be constructed or was newly constructed less than two years before the sale, they can also demand free improvements. This claim is subject to the provisions of the contract for work and labour. This means that the law on sales is partially superimposed on the contract for work and services, which takes account of the economic reality of property projects. This regulation is particularly important for property developer models in which the purchase contract and contract for work and labour are closely linked in economic terms. The sometimes difficult distinction between the law of sale and the law on contracts for work and labour is becoming less relevant in practice, as central protective mechanisms now also apply to the purchase of property.
- Mandatory five-year limitation period (Art. 219a para. 3, Art. 371 para. 3 CO)
Finally, the five-year limitation period for claims for defects remains in place, but may no longer be shortened to the detriment of the buyer or purchaser. Here too, the legislator is creating mandatory law and preventing the contractual erosion of warranty claims. The limitation period continues to commence upon acceptance. In the case of property purchases, the transfer of benefit and risk is generally decisive. The limitation period must be strictly distinguished from the obligation to give notice of defects: While the failure to give notice of defects can lead to forfeiture, the limitation period limits the enforceability of the claim in court. Contractually granted guarantees or extended warranty periods remain possible. The revision sets minimum standards, but does not prevent the parties from agreeing more extensive rights.
Legal categorisation and analysis
The revision represents a shift in the balance of risk in favour of the client. Of particular dogmatic interest is the closer intermeshing of sales and work contract law. Art. 219a CO integrates elements of the contract for work and labour into the purchase of real estate. This takes account of the economic reality that elements of contracts for work and labour regularly dominate the purchase of new buildings. In addition, the legislator creates mandatory standards that supersede dispositive contract law. This represents a significant restriction on contractual freedom in the construction and property sector. General contractors and total contractors are increasingly faced with the question of recourse against subcontractors. As the right to rectification is mandatory in relation to the client, recourse clauses in the internal relationship must be carefully scrutinised and adjusted if necessary. Otherwise, there is a risk of liability being extended without corresponding recourse protection. From a compliance perspective, it is particularly important to emphasise that ineffective clauses not only come to nothing, but can also entail litigation risks in the event of a dispute. If abbreviated clauses continue to be used in general terms and conditions, they may also be considered unfair within the meaning of Art. 8 UWG. This exposes companies not only to risks under civil law, but possibly also under unfair competition law.
Practical implications for companies
For construction companies and general contractors, there is an immediate need to adapt standard contracts. Clauses with shortened notice periods or limited rights to rectification will be invalid in future. At the same time, the liability risk is effectively extended, as defects can be reported more frequently in due time.
Project developers and sellers of new buildings must take into account that buyers can now expressly assert a right to rectification under the contract for work and labour. This affects the economic calculation of projects as well as the structuring of transactions and the contractual distribution of risk between property developers, contractors and purchasers.
Architects and engineers are affected to the extent that planning defects are expressly included in the 60-day notice period. Professional liability insurance policies should therefore be reviewed and adjusted if necessary. For legal counsel and compliance officers, the systematic review of all sample contracts is a priority. Internal processes for recording and processing defects should also be adapted in order to comply with the new legal framework.
Transitional law
The new provisions will generally apply to contracts concluded after 1 January 2026. For existing contractual relationships, the previous law remains authoritative unless a new contractual agreement is concluded after the new provisions come into force. In the case of long-term project developments with staggered contract conclusions, the applicable law must be carefully examined on a case-by-case basis. New law may apply, particularly in the case of subsequent contractual amendments or supplementary agreements.
Conclusion and outlook
The revision of the Swiss Code of Obligations on construction defects brings a paradigm shift in Swiss construction and property law. With the mandatory 60-day notice period, the indispensable right to rectification and the five-year limitation period, which can no longer be shortened, the legislator is strengthening the position of the client.
For companies, this means Contract reviews and amendments are urgently required. Standard clauses should be reviewed in good time and revised with a view to mandatory law in order to minimise liability and litigation risks. Particular attention should be paid to harmonisation with SIA standard 118, liability clauses and recourse provisions in subcontractor chains. Those who ignore the new requirements risk ineffective clauses and lawsuits.
Practice will show how courts interpret the new provisions – especially in the interplay between sales and work contract law. However, one thing is already clear today: from 2026, new rules will apply when dealing with construction defects.
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