The distribution by use: who may design and direct what
The LOE organises competences by the building's use. For administrative, healthcare, religious, residential in all its forms, educational and cultural uses, the design and the works direction belong to the arquitecto (architect). For aeronautical, agricultural, energy, hydraulic, mining, telecommunications, transport, forestry, industrial, naval, sanitation engineering and engineering-ancillary uses, the qualifying degree is that of the engineer or technical engineer according to their specialities. And for all other buildings, qualification is shared between architect, technical architect and the engineering professions according to their competences.
The direction of execution has its own rule: in works of the first group directed by an architect, the execution director is the arquitecto técnico (technical architect). The practical result in ordinary residential building is the classic pair: architect as designer and works director, technical architect as execution director.
Two functions, not two hierarchies
The most widespread misunderstanding reads the pair as hierarchy, the architect commands and the technician assists. The LOE draws something else: two distinct functions with separate liabilities.
| Field | Works director (architect) | Execution director (technical architect) |
|---|---|---|
| Object | The works as development of the design | The material execution of what was designed |
| Content | Technical, aesthetic, planning and environmental aspects | Verification of product reception, execution control, quantitative control |
| Characteristic documents | Design modifications, direction orders, final certificate together with the execution director | Material reception, quality control, valuations and certifications |
| Typical liability | Design and direction errors | Execution control failures |
Each function has its own territory of liability, and the courts treat them as such: a design defect points to the designer and works director, an execution control failure to the execution director. This separation is also why both sign the closing documents together: the final works certificate carries both signatures because it attests both things, that the works are the design and that execution was controlled. The site mechanics of both roles are developed in the article on works direction and execution direction.
The collaboration in practice
Day to day, the distribution works as a division of labour with defined contact zones. The technical architect lives the works in fine grain: material reception with its certificates, unit setting-out, geometric and execution control, measurement of what is actually built, preparation of the certifications. The architect intervenes on the whole: resolving the design's doubts and indefinitions, validating adaptations, governing the architectural and regulatory coherence of the result.
The classic friction zones are predictable and manageable. The site change the technician detects and the architect must resolve: without a fast consultation circuit, the works decide alone. The quality the technician demands and the schedule that presses: the execution direction's authority to reject badly executed units needs the explicit backing of the whole site direction. And the boundary of instructions: healthy practice channels orders through the site order book, with clear authorship, avoiding works directed by conversations.
Economic reading of the duality
For the developer, the duality has a visible cost, two fees, and a less visible value: a control system with built-in separation of powers. The technician certifying what is executed is not the one who designed, and the one controlling quality is not the one who drew the detail: each function reviews the other's work. Well used, that architecture reduces precisely the two most expensive risks of the works, paying for what was not executed and covering up what was badly executed.
The condition of the value is the effective independence of both functions and their real resourcing: site directions bought at the minimum, with scarce visits, turn the separation of powers into a formality of signatures. The commitments are agreed in writing in each appointment contract.
Frequent errors
The first is hiring the pair as an undifferentiated package without defining commitments: the functions are legal, but visits and means are agreed. The frequency of visits and the means are fixed before signing.
The second is bypassing the execution director in the certifications, negotiating them directly between developer and contractor: the independent control of what is paid is lost. Certification passes through whoever controls the executed work.
The third is leaving modifications formally unresolved by the works director, accumulating de facto adaptations without documentary cover. Each modification is recorded in the site order book.
The fourth is confusing the territories of liability when claiming, directing the design defect against the technician or the control failure against the designer, with the wrong lawsuit as a result. Classifying the defect comes before choosing the addressee.
Note: the distribution of competences described is that of article 10 and related provisions of the consolidated LOE; singular cases and mixed-use works require specific analysis of qualifying degrees.