1. What are we talking about? The strongest of construction warranties
In Morocco, a new building is covered by three successive warranties, of increasing intensity over time. The completion warranty (1 year after acceptance) requires the repair of all reported defects. The biennial warranty (2 years) covers equipment elements separable from the structure. And the decennialwarranty (10 years) — the most powerful — engages the builders' liability for the most serious defects.
This framework is notably recalled in our guide on the dispute against a property developer and backed, depending on the operation, by the law 44-00 on VEFA and the Code of Obligations and Contracts. The decennial has a particularity: it targets builders in the broad sense — the contractor who executes, but also the architect for the design and, where applicable, the supervision of the works.
2. Which defects does the decennial cover?
The decennial does not cover just any defect. It targets two families of defects, and it is their qualification that decides everything:
- Defects that compromise the soundness of the works: evolving structural cracks, foundation defects, subsidence, damage to the structural works. The building, or part of it, sees its stability threatened.
- Defects that render the works unfit for their purpose: a generalised waterproofing failure that makes a dwelling uninhabitable, chronic infiltrations, a flaw that prevents the use of the property for its intended purpose — even without immediate threat to the structure.
Conversely, purely aesthetic defects, or those affecting only separable equipment elements (taps, shutters, air conditioning), fall in principle under the biennial and not the decennial. It is a technical boundary, not just a legal one: the same crack may be trivial or decennial depending on whether it is stabilised or active, superficial or structural. See also our hidden-defects case study in Casablanca, where the distinction between a stabilised crack and an active crack made all the difference.
3. The starting point of the period: acceptance of the works
The decennial period runs from the acceptance of the works — the act by which the client accepts the works, with or without reservations. It is the pivotal event: without a clearly dated acceptance, the starting point of the period becomes debatable, and the remedy fragile.
Hence the importance of the acceptance report and its reservations. Our article on the acceptance of a new dwelling and the wording of reservations details why signing an acceptance without reservations can weaken your rights over apparent defects. For sets handed over to a property manager, the technical handover to the condominium manager of a new building is the moment when the actual condition of the works must be observed on an adversarial basis.
The reflex: have the defect observed by an expert before any repair
The first mistake, faced with a defect, is to repair in a hurry — and destroy the evidence. Until the defect has been observed in situ by an independent expert, the decennial remedy rests on photos and memories. Yet the decennial requires a demonstration: that the defect affects soundness or renders the property unfit for its purpose, and that it stems from a construction fault and not a maintenance failure. A report compliant with RICS standards — time-stamped surveys, measurements (crack gauge, moisture meter), tracking of the evolution, cause analysis — establishes these points before the situation changes. The timing is comfortable: report delivered within 5 to 8 days (48-72 h express).
4. Who is responsible? Contractor, architect — or both
The decennial targets builders. In practice, two actors are on the front line, and their share of liability depends on the origin of the defect:
- The contractor, when the defect stems from an execution fault: non-conforming materials, defective workmanship, breach of the rules of the trade.
- The architect, when the defect stems from a design flaw — an unsuitable technical approach — or from insufficient site supervision where they were in charge of it.
- A shared liability, frequent in practice: a design flaw aggravated by mediocre execution. The apportionment then turns on each party's causal share.
This is precisely where expertise is indispensable: only a technical examination makes it possible to link the defect to its cause — design, execution, maintenance, external event — and therefore identify the party or parties to be brought in. Without this attribution, the remedy shoots in the dark.
5. The role of expertise: qualify, attribute, price
A solid decennial remedy rests on three demonstrations, and each is the work of an expert:
- Qualify the defect: does it indeed fall under the decennial (soundness / unfitness for purpose) rather than the biennial or the simple completion warranty? The boundary is technical — severity, evolving character, impairment of use.
- Link the defect to its cause: design flaw, execution fault, materials, or external cause. This is what determines the applicable warranty and the responsible party.
- Price the repair: cost of the remediation works according to the rules of the trade, and where applicable loss of enjoyment during the works. An independent costing avoids accepting an undervalued indemnity.
An independent appraisal report compliant with RICS standards documents these three points with a traceable methodology: adversarial visit, instrumented measurements, documentary analysis (acceptance report, plans, contracts), tracking of the evolution of the defects. It is the piece that structures the amicable negotiation with the builder and their insurer. Cost: from 3,500 MAD excl. tax, report within 5 to 8 days (48-72 h express).
6. Amicable first — and the boundary with the judicial
The majority of defects are settled without litigation: documented formal notice to the builder, independent expertise establishing the defect and its cost, then negotiation. The report, sent to the builder (and often to their insurer), opens a discussion on a priced technical basis rather than on assertions.
Beware an essential distinction, detailed in our article amicable expertise vs judicial expertise: the private expertise you commission serves to negotiate and decide. If the matter goes to court, it is the judge who appoints the judicial expert; the private expertise does not replace that appointment. In practice, a rigorous amicable file — defect qualified, cause established, repair priced — is often what makes it possible to reach an agreement before it comes to that.
7. The pitfalls that lose a decennial remedy
- Repairing before having it observed: you remove the evidence of the defect and its cause. Always have it observed in situ first.
- An undocumented acceptance: without a dated acceptance report, the starting point of the 10-year period becomes contestable.
- Confusing the warranties: invoking the decennial for a defect that falls under the biennial (or vice versa) weakens the whole argument.
- Letting time slip: the defect worsens, and the ten-year window from acceptance does not reopen.
- Accepting an indemnity without an independent costing: the builder offers an amount for repairs that are worth more. The expertise gives the right order of magnitude.
8. FAQ
Does the decennial warranty also apply to a house I had built myself?
Decennial liability targets the builders who worked on the works — contractor, architect. If you had it built through these parties, you are in principle the beneficiary of the warranty as the client. The exact terms depend on the contracts signed and the applicable regulations: confirm your situation with your lawyer.
What to do first when faced with a defect I believe to be decennial?
Do not repair right away. Have the defect observed in situ by an independent expert, who will establish its nature, cause and repair cost. Check the date of acceptance of the works (the starting point of the period). Then send a documented formal notice to the builder, backed by the report.
Can the private expertise be used against the builder?
The private expertise serves to negotiate and decide: it is a solid technical basis for the amicable discussion with the builder and their insurer. But if the dispute goes to court, it is the judge who appoints the judicial expert. The private expertise does not replace that appointment — it prepares and strengthens your file.
How long do I have to act?
The decennial warranty covers the defects within its scope for ten years from the acceptance of the works. The terms of action and the other periods (completion, biennial, warranty action) vary according to the basis: have your precise timeline validated by a lawyer without delay, because the worsening of a defect does not wait.
How much does an expertise cost and in what timeframe?
A technical expertise of defects starts from 3,500 MAD excl. tax, depending on the surface, the complexity of the defect and any need for in-depth investigations. The report is delivered within 5 to 8 working days, 48-72 h express. Firm quote within 24 h.
A defect on your works? Have it observed before you repair.
RICS-certified experts — qualification of the defect, attribution to its cause and costing of the repair, in a report compliant with RICS standards. Within 5 to 8 days (48-72 h express), anywhere in Morocco.
Note: The construction warranties (completion, biennial, decennial) and their regime fall under the applicable regulations, notably law 44-00 on VEFA and the Code of Obligations and Contracts depending on the operation. The exact scope, periods and liabilities are assessed case by case: confirm your situation with your lawyer. To document and price a defect, see our real estate appraisal page or the real estate blog.