Expert article
Defect management under VOB/B: a chain, not a form
Managing defects is not about keeping lists. It is about holding a chain together — break one link and the claim is gone, however well founded it was.
Expert article by Open Experience GmbH. · As of: August 2026
What is defect management in construction?
Defect management is the continuous handling of construction defects from discovery through to sign-off: recognising the defect and documenting it so it holds up as evidence, notifying the responsible party with a deadline, supervising the rectification, accepting the remedial work and tracking the warranty period. VOB/B, the German construction contract procedures, treats three phases differently — during construction (§ 4 para. 7), at acceptance (§ 12) and afterwards (§ 13).
The three phases — and what changes in each
The same defect is handled differently depending on when it appears. Get the phase wrong and you reach for the wrong legal basis.
| Phase | Legal basis | Who has to prove what |
|---|---|---|
| *During construction* | § 4 para. 7 VOB/B — replace defective work at own cost | The contractor owes work free of defects |
| *At acceptance* | § 12 VOB/B — protocol with reservations | Known defects must be reserved or they are lost |
| *After acceptance* | § 13 VOB/B — defect claims within the limitation period | The client has to prove the defect |
The switch at acceptance is the most important moment of the construction contract: with it, the burden of proof reverses.
Phase 1 — during construction
Work recognised as defective while building is still under way must be replaced by the contractor at their own expense (§ 4 para. 7 VOB/B). This is the cheapest phase: the defect is still accessible, the firm is still on site, and nobody is arguing about responsibility.
- The most expensive mistakeDefects not documented before building elements are closed up. What disappears behind screed, plaster or waterproofing can afterwards only be proven by opening the element again.
- Supervision-intensive tradesWaterproofing, insulation, junctions: here the duty to supervise intensifies — and here complete documentation pays for itself.
- Right to terminateIf the contractor fails to remedy despite a deadline, the client may withdraw the contract (§ 4 para. 7 in conjunction with § 8 para. 3 VOB/B).
Phase 2 — at acceptance
Acceptance is the hinge. Anyone who fails to expressly reserve known defects in the protocol loses the claims arising from them — likewise the contractual penalty if it is not reserved. The acceptance protocol is therefore not a form but the stocktake against which everything will be measured years later.
- What belongs in the protocolEvery defect found, individually, with location and a deadline for rectification — plus the express reservations.
- Outstanding work is not a defectWork not yet performed and work performed defectively are different things and belong in separate records.
- When the period startsAcceptance starts the limitation period for defect claims — the date in the protocol is the most important figure in the project.
Phase 3 — after acceptance
Now the client carries the burden of proof. The sequence is always the same: establish and evidence the defect, give written notice with a reasonable deadline, secure receipt, supervise the rectification, accept the remedial work, sign it off — and keep an eye on the fresh two-year period for that remedial work.
- Once the deadline passes without resultSelf-remedy at the contractor's expense (§ 13 para. 5 no. 2 VOB/B), price reduction or damages — all of it presupposes the documented notice with a deadline.
- Sign-off is a step of its ownA defect is not settled because somebody considers it settled. The remedial work is inspected and the result recorded.
- Warranty across yearsFour or five years run on long after the project team has moved elsewhere. What is not in a system simply expires.
Where the process fails in practice
A spreadsheet as the defect list
No timestamps, no photo links, no deadline monitoring — and three versions in circulation.
No responsible party
A defect without an addressee is worked on by nobody.
Deadline without a reminder
Deadlines nobody is reminded of expire. Reliably.
No sign-off
The defect is marked "done" and nobody has inspected it.
A break at acceptance
The construction-phase list and the warranty list are two separate files — the chain snaps at exactly the point that matters most.
Better
One record per defect that survives acceptance and carries the warranty period with it.
A chain that does not break
In Construction Defects the defect stays one and the same record — from capture on site, through the acceptance protocol, into the warranty phase. Photo, position on the plan, responsible party, deadline, receipt of the notice, rectification and sign-off hang together in one place. No transfer between phases, no second list, no break at acceptance.
Frequently asked questions
When does defect management begin?
With the first construction progress, not with acceptance. What is documented during construction is later the only evidence of conditions that are no longer accessible.
Who may record defects?
Anyone involved can record them; the recording is owed by the site supervisor as a basic service of construction supervision (service phase 8 of the German HOAI).
What is the difference between a defect and outstanding work?
A defect is work performed but not in conformity with the contract. Outstanding work has not been performed at all. The two are handled separately.
Do subcontractors need their own accounts?
It is not required, but almost always sensible: whoever sees the defect directly in their own account and signs off the rectification there shortens the chain by two transfer errors.
How long must the documentation be kept?
At least beyond the limitation period. Because of possible secondary liability, considerably longer is advisable.
Does a defect reported by an occupant count?
Yes — but for the deadline it is the notice to the contractor that counts. A report arising from use therefore has to find its way into the record.
One record that survives acceptance.
In 45 minutes we show a defect's path from the site to the end of the warranty period — with no change of system in between.