Defects liability in construction: your rights when defects occur

Defects liability in construction obliges the contractor to rectify defects in their work free of charge within a statutory period. Under BGB, this period is five years from acceptance; under VOB/B, four years. According to the BSB/IFB Project Owners' Report 2025, an average of 31 defects is identified in private construction projects.¹ Knowing your rights can save considerable money and trouble when problems arise.

Key points at a glance

• BGB contract for work: 5 years of defects liability from acceptance (§ 634a BGB) — applies to most private project owners
• BSB/IFB Report 2025: average of 31 defects per private construction project — always document acceptance in writing with a formal record
• After acceptance, the burden of proof reverses: you must prove the defect and its cause — thorough documentation is essential
• Reducing periods below 5 years through standard terms is unenforceable against consumers under § 309 no. 8b BGB

Overview of defects liability periods

Different periods for rectifying defects apply depending on the contract type. The table below shows the main rules:

For private project owners, a BGB contract for work with five years of defects liability applies in most cases. VOB/B (German Construction Contract Procedures) is primarily used for commercial clients. If VOB/B is agreed in the contract, the period falls to four years.²

When purchasing a flat from a developer, sales law (§ 438 BGB) applies, also providing five years.² Here, however, the period begins on handover rather than formal acceptance.

Important: VOB/B only applies if expressly agreed in the contract and the client, as a consumer, is familiar with VOB/B in its entirety. Otherwise, BGB rules apply.

When does the defects liability period begin?

The defects liability period begins at acceptance. Without acceptance, the period does not start. This sounds simple, but is a frequent source of errors in practice.

Formal acceptance

During formal acceptance, the project owner and contractor jointly inspect the work, check it and record the result in an acceptance report. Any defects noticed are documented and the contractor is asked to rectify them. This is the safest option because both parties have a clear date and written basis.

Implied acceptance

If you simply use the work without expressly accepting it, implied acceptance may occur. Beginning to use a completed bathroom or new heating system can be treated as acceptance. The problem: the exact date is difficult to establish later.

Deemed acceptance under § 640 para. 2 BGB

Since the BGB reform, the following applies: if the contractor requests acceptance in writing after completion and you do not respond within a reasonable period, the work is deemed accepted. The period must be reasonable; 12 working days is generally used.²

Specifically, this means: always respond to a request for acceptance. If you have identified defects, communicate them in writing. Otherwise, the defects liability period begins without you having asserted those defects.

Recommendation: Always insist on formal acceptance with a written record. This protects both sides and establishes a clear start date for defects liability.

Which defects fall under defects liability?

A defect within the meaning of § 633 BGB exists if the work does not have the agreed characteristics or is unsuitable for normal use.² The decisive factor is the difference between what was contractually owed and what was actually delivered. DEKRA points out that distinguishing a defect from a normal deviation often requires a technical construction assessment by an independent surveyor.⁵

Typical construction defects

• Cracking in walls, ceilings or screed exceeding normal shrinkage
• Moisturecaused by defective waterproofing (e.g. in the cellar, bathroom or around windows)
• Wrong materials: A different product was installed from the one agreed in the quote
• Poor workmanship: Uneven tiles, ill-fitting windows, untidy joints
• Failure to meet standards: Thermal insulation does not meet the requirements of the Building Energy Act (GEG)⁶, electrical installation breaches VDE regulations⁷
• Functional defects: Heating operates inefficiently, drainage falls in the wrong direction

What is not covered by defects liability?

Normal wear and tear are not defects. If floor tiles show signs of use after three years, this is not a defects liability claim. Nor is it covered if changes you made yourself caused the defect.

Cosmetic flaws that were visible at acceptance but not raised are also difficult to pursue later. This is why thorough acceptance is so important.

Your rights for construction defects: step by step

If you identify a defect after acceptance, you have clearly defined entitlements as the project owner. The process follows a set sequence.

1. Document the defect

Record the defect immediately. Photograph it from different angles, note the date and describe exactly what is wrong. The more precise your documentation, the stronger your position in any later dispute.

2. Written defect notice with a deadline

Inform the contractor of the defect in writing. Set a reasonable rectification deadline (generally 14 days, shorter for urgent defects). The consumer advice centre recommends sending the notice by registered post with acknowledgement of receipt so that delivery can be proved.³ Describe the defect specifically and refer to § 637 BGB.² You can find a specific wording template in the Sample defect complaint letter.

3. Request rectification

The contractor has the right and duty to rectify the defect themselves. They are generally allowed two attempts. During this phase, you must give them access to the work. Do not refuse rectification, otherwise you risk losing further entitlements.

4. If rectification fails

If rectification fails or the deadline passes without a response, four options are available:

• Price reduction: You keep the work but pay less. The reduction reflects the loss in value caused by the defect.
• Substitute rectification (§ 637 BGB): You appoint another contractor to repair the defect and reclaim the cost from the original contractor. The rectification deadline must have expired first.
• Damages:If the defect causes further losses (e.g. hotel costs because the property is uninhabitable), you can claim these.
• Rescission: For serious defects, you can withdraw from the contract. This rarely happens in practice because construction work is difficult to reverse.

Common defects liability traps

In practice, many project owners fail because of avoidable mistakes rather than a lack of rights. We regularly encounter the following pitfalls:

Shortened periods in standard terms

Some contractors attempt to reduce the defects liability period to two or three years through their standard terms. This is unenforceable against consumers under § 309 no. 8b BGB. The statutory five-year period still applies.² Nevertheless, raise such clauses before signing, as they may indicate the business's approach to contracts.

Overlooking deemed acceptance

As described above, if you ignore an acceptance request, the work is deemed accepted once the deadline expires. The defects liability period then starts and the burden of proof reverses. Always respond.

Missing documentation

Without photos, a date and a written defect notice, enforcing a defects liability claim becomes difficult. Verbal agreements are almost impossible to prove in a dispute. Document everything in writing, including discussions and promises.

Subcontractor issues

If your contractor uses subcontractors, they remain responsible to you for defects liability. They cannot rely on a subcontractor having caused the defect. That is their internal problem, not yours. Nevertheless, ensure the contract regulates whether subcontractors may be used.

Reversal of the burden of proof after acceptance

Before acceptance, the contractor must prove their work is free of defects. Afterwards, the burden of proof reverses: you, as the project owner, must prove that a defect exists and was caused by the contractor.³ Acceptance is therefore the most critical moment in the entire construction process.

Suspending limitation: how to secure your claims

If the defects liability period is about to expire and the contractor is not responding, you have three options to stop limitation:

Independent evidence proceedings (§ 485 ZPO)

This is the most common method in practice. You apply to the competent court for independent evidence proceedings. A court-appointed expert assesses the defect. The limitation period is suspended for the duration of the proceedings. The losing party ultimately bears the costs.

The advantage: you obtain evidence admissible in court without immediately having to bring a claim. The expert report often prompts the contractor to agree voluntarily to rectify the defect.

Negotiations (§ 203 BGB)

If you negotiate the defect with the contractor, limitation is suspended for the duration of the negotiations (§ 203 BGB).² Important: record the start and progress of negotiations in writing. A simple complaint by telephone does not count as negotiation in the legal sense.

Bringing legal proceedings

Filing a claim suspends limitation from the day it reaches the court. This is the most decisive measure, but also the most expensive. In most cases, independent evidence proceedings are the better first step.

Why reviewing the quote before construction is crucial

Most defects liability disputes originate in the contract rather than on site. Missing or unclear defects liability clauses, vague specifications and opaque contractual rules leave project owners poorly placed when defects occur.

Anyone who has their construction quote reviewed before signing can identify such weaknesses in time. A professional quote review reveals, among other things:

• Whether the defects liability period is stated correctly or unlawfully shortened
• Whether the specification is precise enough for a defect to be clearly established
• Whether the contract includes rules on acceptance, rectification and defect notices
• Whether the contract type (BGB or VOB/B) is clearly named and what it means for your rights

Particularly with variation risks , the close relationship between defects liability and quote quality becomes clear: missing quote items lead not only to additional costs, but also disputes about whether defects stem from rectification or the original scope of work.

How much does a quote review cost in comparison?

Compared with the costs of a legal dispute or independent evidence proceedings (easily 2.000 to 5.000 euros), a prior quote review offers modestly priced protection. Anyone who has their construction contract systematically reviewed significantly reduces the risk of subsequent defects liability problems.

Frequently asked questions about defects liability in construction

How long does defects liability apply to contractors' work?

Under a BGB contract for work, the defects liability period is five years from acceptance. If VOB/B is contractually agreed, it is four years. For private project owners, BGB generally applies unless VOB/B has been expressly incorporated.²

Can a contractor exclude defects liability?

A complete exclusion of defects liability against consumers is not possible. A reduction to less than one year through standard terms is also unenforceable under § 309 no. 8b BGB. In an individually negotiated contract, the period can be reduced to one year, but only if the project owner has individually agreed. This rarely happens in practice.

What should I do if the contractor does not respond to the defect notice?

Set a further written deadline with a specific date. If this also passes, you can choose substitute rectification under § 637 BGB: appoint another business and reclaim the costs from the original contractor. For larger sums, independent evidence proceedings to preserve evidence are advisable beforehand.

Does defects liability also apply to undeclared work?

No. If the work was carried out without an invoice (a so-called “no-invoice agreement”), the contract for work is void under § 1 para. 2 of the Act to Combat Undeclared Work. You then have no defects liability claims. The contractor also has no payment claim. Both sides are left without rights.³

When should I involve a solicitor?

If the contractor refuses rectification, the cause of the defect is disputed or damage exceeds 5.000 euros, legal advice makes sense. Independent evidence proceedings are often worthwhile beforehand to establish the facts objectively. Specialist construction and architectural law solicitors handle these cases.

Sources

1. BSB/IFB, Bauherren-Schutzbund / Institute for Building Research – Project Owners' Report 2025: average of 31 construction defects per project
2. Gesetze im Internet, § 633 BGB, § 634a BGB, § 637 BGB, § 640 BGB, § 203 BGB, § 438 BGB, § 309 no. 8b BGB
3. Consumer advice centre – checking contractors' invoices: defect notices and burden of proof
4. BSB, Bauherren-Schutzbund e.V. – guide to construction defects and defects liability
5. DEKRA: technical construction inspection and expert assessment
6. Building Energy Act (GEG): requirements for buildings' energy performance
7. VDE, Association for Electrical, Electronic and Information Technologies: VDE rules for electrical installations

Further reading: Reviewing a construction quote: the complete guide · Avoiding variation costs · Reviewing a construction contract: what matters