Scenario: three years after hand-over and the end of the contractual defects liability period, a plant discovers spreading structural floor cracks and fundamentally failed waterproofing — repair costs estimated at 8 billion dong. The owner asks the seemingly simple question: “The warranty has expired — is the contractor still liable?” The real answer is “yes — but under different liability layers, with different proof conditions”. This article separates the three post-warranty liability layers and explains why latent defects are a battlefield of causation inspection.
Three entirely different liability layers after the warranty expires
- Layer 1 — Contractual warranty (DLP): during the contract’s defects liability period, the contractor must return and repair in-scope defects without the owner proving “fault” in the full legal sense. When this layer ends, the free-repair duty under that mechanism ends — this is the only part that truly “expires” with the warranty;
- Layer 2 — Statutory works warranty: Vietnamese construction law sets minimum warranty periods for works by type/grade from acceptance, partly independent of the parties’ agreement — this frame must be checked for the specific works before concluding “all warranty is over”;
- Layer 3 — General damages liability: if defective construction/design causes loss to the owner or third parties, damages claims under civil law for breach of contract and/or non-contractual liability do not die on the warranty expiry date — they live by the limitation period and the ability to prove the defect existed from construction/design. A warranty is a “procedural privilege”, not a shield exempting all later liability.
Latent defects: why causation inspection is the centre
A latent defect existed from construction/design but could not be detected by ordinary acceptance inspection, surfacing only years later: improperly treated foundations, missing reinforcement, wrongly layered waterproofing, concealed non-conforming materials. Latent-defect cases are won or lost on one question: what caused the damage — with only three candidates: (a) construction/design/material fault of the contractor and designer; (b) owner operation/maintenance fault (floor overloading, changed use, unmaintained systems); (c) natural wear and external events. A qualified independent inspection organisation “reads” the damage like a medical record — crack patterns, locations, load history, original construction files (diaries, material test results, covered-works acceptance minutes) — to assign the cause.
The practical consequence: on discovering a post-warranty defect, do not repair immediately. Repairing destroys the scene, i.e., the evidence — the right sequence is recording the status, inviting the contractor to witness, causation inspection, and only then deciding repair and recovery. An owner who repairs in operational haste may win on schedule and lose the entire money claim.
The recovery roadmap for defects found after warranty
- Check the limitation clock first: contract/damages limitation runs from when the right was infringed or damage was discovered depending on claim structure — late-discovered defects must still fit the permitted frame; this decides whether there is a case at all, before any technical analysis;
- Lock the liability chain: whether the defect belongs to the main contractor, a subcontractor, the design consultant or the supervisor — the original contracts and acceptance files decide the right defendant; suing the wrong party costs years;
- Quantify with discipline: reasonable repair cost on the minimally necessary technical solution (no “opportunistic upgrades” billed to the contractor), documented interruption losses, minus natural-wear portions matching the works’ age;
- Negotiate from the inspection file: with a strong causation report, most latent-defect matters settle as repair-cost sharing rather than full litigation — because the contractor also understands its reputation and cost exposure if it loses.
Frequently asked questions
Is the contractor still liable for defects found after the warranty expires?
Yes, under other layers: the free-repair duty inside the contractual defects liability period (DLP) ends; but minimum statutory construction warranty for the works type must be checked separately, and damages liability for construction/design defects survives within the limitation period — warranty expiry is not a blanket exemption.
What are latent defects and how are they claimed?
Defects existing from construction/design that ordinary acceptance could not detect, surfacing years later. Claiming requires independent inspection proving the cause is construction/design/material fault — not faulty operation or natural wear — plus a limitation check and identifying the right liable party in the contracting chain.
What is the first thing to do on finding a post-warranty defect?
Do not repair at once. Record the status, invite the contractor to witness, and commission causation inspection by a qualified independent organisation. Hasty repair destroys the scene, i.e., the evidence — winning operational time but losing the recovery right.
What if the owner’s own faulty operation caused the damage?
Causation inspection allocates: construction/design fault portions to contractor/designer; overloading, changed use and missing maintenance portions to the owner; natural wear to nobody. Post-warranty disputes therefore always start with causation inspection, never with a demand letter.
This article has been quality-reviewed by the FLAW AI Legal Council