Contractor and main contractor

	Main contract	Separate trades
Number of contracts	one	as many as there are trades
Coordination	borne by the contractor	borne by the client or delegated
Counterpart when a defect arises	one	that of the trade concerned, to be identified
Breyne Act protection	applicable if the other conditions are met	excluded

The last line weighs most heavily, and it is covered in the article on the single contractor test.

A mechanism little known to private clients, and yet decisive. It concerns the approval of contractors.

Approval is an administrative recognition attesting that a firm has the technical and financial capacity to carry out works of a given nature and scale. It is graded by category and by class.

Two main effects.

In public contracts it governs access to certain contracts, according to the category and class required, covered in the guide on measurement and specification.

In private contracts under the Breyne Act it determines the guarantee regime. An approved contractor provides security of a limited amount; a non-approved party must provide a guarantee covering the whole.

That very differentiation has been held contrary to European law by the Court of Justice of the European Union, as developed in the article on payments, guarantees and security.

For a private client, checking approval therefore remains useful today, while knowing that the attached regime is set to change.

Three real advantages, beyond the apparent simplicity. They relate to the single point of contact, coordination and the guarantee.

A single counterpart. When a defect arises, the client need not determine which trade is at fault before acting.

Coordination included. Sequencing, interfaces between trades and arbitration fall to the contractor.

Statutory protection, where applicable. Where the other conditions are met, the arrangement triggers the Breyne Act.

Those advantages have a price, corresponding to the coordination margin and the assumption of interface risk. It is addressed from the cost angle in the guide on construction costs per m².

Two symmetrical advantages, and a burden. They relate to price, choice of firms and coordination.

The choice of each firm, with the ability to select specialists rather than inherit a third party's subcontractors.

Transparency of prices by trade, without an intervening coordination margin.

In return, coordination falls to the client unless delegated, with the corresponding responsibilities and without the Breyne Act's protection.

The point not to miss: this arrangement presupposes a coordination capability few private clients possess, and its absence is paid for in delay and interface disputes.

Five consequences, often discovered afterwards. They concern coordination, time and liability.

The statutory regime, with or without the Breyne Act.

The number of guarantees to obtain and monitor, one per contract.

The complexity of acceptance, covered in the branch on acceptance.

Identifying who is responsible for an interface defect, markedly harder in separate trades.

The architect's role, whose supervision of execution bears on more counterparts.

This choice is therefore made at brief stage, not at tender stage. Revisiting it during the project means reworking the whole contractual arrangement.

Four rules.

Put the arrangement choice at brief stage, setting out its legal and not merely organisational effects.

Check approval where it governs a guarantee or access to a contract.

Do not present separate trades as a simple saving, coordination being real work that falls to someone.

Document the choice and its rationale, since it governs the whole applicable regime.