When buying a house in Switzerland, statutory warranty rules, notarial drafting and strict notice duties operate together. The core provisions are Arts. 197-210 of the Swiss Code of Obligations, supplemented by the land sale rules in Arts. 216 et seq. CO. The practical question is whether the defect was warranted, visible, hidden or fraudulently concealed.
Under Art. 197 CO, the seller is liable if the house lacks warranted qualities or has substantial defects. For a detached house in Zurich sold for CHF 1'500'000, a warranted heat pump that does not work can therefore trigger warranty remedies. Art. 201 CO requires the buyer to inspect and notify defects promptly once the property can be checked. Under Art. 205 CO, the buyer may seek rescission, a price reduction or, in defined cases, damages.
Swiss real estate contracts often exclude statutory warranty extensively, commonly using wording similar to sold as seen. The exclusion must be included in the notarised deed, because Art. 216 CO requires public notarisation for a land purchase, whether in Bern, Geneva or Basel-Stadt. A broad exclusion may cover visible and unknown defects, provided the law allows it. It does not normally remove liability for expressly warranted characteristics, such as an approved living area of 180 m².
Art. 199 CO does not protect a seller who fraudulently conceals defects. Fraud may be inferred where repeated water ingress in Ticino was known but walls were freshly painted before viewings. Concealed contamination, asbestos boards or missing building permits can also matter if they would have affected the purchase decision or price. The buyer must prove deception, using emails, previous quotations for CHF 80'000 remedial works, insurance files or statements from tradespeople.
Art. 210 CO provides a basic two-year limitation period for sales-law defect claims from delivery. A five-year period applies under Art. 210 para. 2 CO where goods were intended to be integrated into immovable works and caused the defect. For defects in a building sold with land, Art. 219 para. 3 CO also refers to five years from acquisition of ownership. These limitation periods are separate from the notice duty under Art. 201 CO, which may require action within days of discovery.
A technical inspection before signing reduces disputes, but it does not replace careful contract drafting. In practice, short reports for detached houses in cantons such as Aargau, Vaud or St. Gallen often cost about CHF 1'500 to CHF 3'500, depending on scope. The expert should check the roof, damp, electrical systems, heating, contamination indicators and deferred maintenance; for condominium ownership, minutes, reserve funds and regulations also matter. FINMA-supervised lenders assess loan-to-value, equity and affordability under SBVg practice, but they do not identify every hidden construction risk.
When a defect is found, the buyer should preserve evidence immediately, take photographs, obtain quotations and notify the seller by registered letter. The notice should describe the defect precisely, refer to Art. 201 CO and reserve rights under Arts. 197 et seq. CO. Emergency measures, for example against incoming water, are permissible but should be documented and limited to what is necessary. Limitation periods must then be checked, and depending on the canton the next step is conciliation or court action; tax consequences can be reviewed using ESTV and cantonal guidance.