The architect’s role in Spanish property: projects, peritos and what your arquitecto does

A guide to the statutory roles an architect plays when you build, renovate or survey property in Spain.

In Spain, the architect (arquitecto) is not a designer you hire for ideas and then set aside. Under the Ley 38/1999 de Ordenacion de la Edificacion (LOE), the architect is a legally defined agent of the construction process with specific statutory obligations, professional liability and the exclusive habilitating titulation for residential building work. If you are building a villa, structurally renovating an apartment or commissioning a pre-purchase structural assessment on the Costa del Sol, the architect is central to the process. This guide explains the three roles the Spanish architect plays: proyectista (project author), director de obra (site director) and perito (expert witness), and how each fits into the buying, building and owning cycle.

What does the proyecto de obra include and who can write it?

The proyecto de obra is the comprehensive technical document set that defines and determines the construction works. Under LOE article 4, it must technically justify every proposed solution and is the basis on which the town hall issues a building licence (licencia de obra mayor). Without an approved proyecto, no licencia de obra mayor can be granted.

The proyectista, defined in LOE article 10, is the agent who redacts the project at the promoter’s commission and in compliance with technical and urbanistic regulations. For residential property (LOE article 2, group a: administrative, sanitary, religious, residential, educational and cultural uses), the habilitating titulation is exclusively that of architect. This means no other professional can legally author the main building project for a home. The architect verifies the geotechnical conditions, designs the structure within the constraints of the town plan (PGOU or PGOM), ensures compliance with the Codigo Tecnico de la Edificacion (CTE) and produces the memory, plans, specifications and budget that constitute the proyecto.

The proyecto must be visado (stamped) by the relevant Colegio de Arquitectos before it is filed at the town hall. The visado, governed by Ley 2/1974 de Colegios Profesionales, is the college’s verification that the architect is colegiado (registered), up to date with professional obligations and that the project meets minimum technical requirements. It is not a substitute for town hall approval but a prerequisite for it.

What is the difference between direccion de obra and direccion de la ejecucion?

Spanish construction law splits site supervision into two legally distinct roles, a distinction that confuses foreign buyers familiar with a single project manager or clerk of works.

The director de obra (LOE article 12) is the architect who directs the development of the build in its technical, aesthetic, urbanistic and environmental aspects, ensuring it conforms to the approved project, the building licence and the contract. Key obligations include verifying the replanteo (setting out) and that foundations and structure match the geotechnical study, resolving contingencies during construction, recording instructions in the Libro de Ordenes y Asistencias, and signing the certificado final de obra. For residential property, this role is reserved to the architect.

The director de la ejecucion de la obra (LOE article 13) is typically the arquitecto tecnico (also known historically as the aparejador), who controls the material execution and quality of construction. This agent verifies the reception of construction products on site, orders tests and trials, checks replanteos, materials and the correct execution and placement of structural elements and installations, and co-signs the certificado final de obra alongside the director de obra. For residential projects directed by an architect, the habilitating titulation for this role is that of arquitecto tecnico.

The same architect can hold the director de obra role while a separate arquitecto tecnico handles the direccion de la ejecucion. Alternatively, where permitted, the director de obra may also assume the article 13 obligations, though in practice the two-role split is standard for obra mayor projects in Andalusia.

What is the certificado final de obra and why does it matter?

The certificado final de obra is the document confirming that the completed building conforms to the approved proyecto. It is subscribed jointly by the director de obra (architect) and the director de la ejecucion (arquitecto tecnico), as required by LOE article 12.3.e and 13.2.e.

Under LOE article 6, the acta de recepcion (formal handover) records the date of the certificado final de obra, the final material execution cost, and the declaration of acceptance with or without reservations. The plazo de recepcion is 30 days from completion; if no reservations or rejections are raised, receipt is deemed tacit. Crucially, the liability periods under LOE article 17 run from the acta de recepcion, making this document the legal starting point for all warranty claims.

The certificado final de obra also triggers the town hall licencia de primera ocupacion (first occupation licence), which confirms the completed building matches the approved project and is fit for habitation. Without it, a property cannot be legally occupied or registered as a dwelling. For buyers of new-build property on the Costa del Sol, confirming the certificado final de obra exists and the licencia de primera ocupacion has been issued is a core due diligence step.

What is an informe pericial and when do you need one?

An informe pericial is a technical expert-witness report prepared by a college-registered architect (or other qualified profesional) for use in legal proceedings. Unlike a pre-purchase structural survey, which is a private advisory document, the informe pericial is designed to be presented as evidence in court (peritaje judicial).

Common situations where an informe pericial is required include:

Situation	What the perito assesses
Construction defect dispute	Whether defects exist, their cause, who is liable under LOE article 17, and remediation cost
Cadastral value challenge	Whether the valor catastral is excessive relative to actual construction quality and market value
Structural survey after purchase	Hidden defects not visible at handover, within LOE liability windows
Insurance claim	Cause and extent of structural or water damage, and whether it falls under the decenal guarantee
Boundary or party-wall dispute	Structural implications of neighbouring works under the Codigo Civil and LPH

The architect preparing the informe pericial must be colegiado and is typically a member of the Agrupacion de Peritos of the relevant Colegio de Arquitectos. The report carries professional liability and is subject to cross-examination in court. For non-resident owners disputing construction quality from abroad, the informe pericial is often the decisive document.

Spain has no direct equivalent of the UK RICS building survey. The closest functional equivalent for a pre-purchase structural assessment is an informe tecnico prepared by an arquitecto or arquitecto tecnico. The distinction matters: an informe tecnico is advisory, while an informe pericial is a formal evidentiary document prepared for litigation.

How does the LOE liability framework protect property owners?

The LOE article 17 establishes a tiered liability structure that runs from the acta de recepcion:

Liability period	Covers	Applies to
Ten years (decenal)	Structural defects affecting foundations, supports, beams, floor slabs, load-bearing walls and mechanical resistance or stability	All agents involved in the structure
Three years	Habitability defects affecting construction elements or installations (hygiene, noise, energy, safety in use)	Constructor and other agents
One year	Finish and completion defects (acabados)	Constructor

For residential property, the ten-year structural guarantee (seguro decenal) is mandatory under LOE article 19. The promotor must secure an insurance policy covering structural damage for ten years from the acta de recepcion, and individual agents carry professional liability that is individualised by default under article 17.2. Solidaria (joint and several) liability applies only when the cause of damage cannot be individualised or where there is concurrence of faults, or always for the promotor under article 17.3.

The director de obra and director de la ejecucion who sign the certificado final de obra are specifically responsible under article 17.7 for its veracity and accuracy. An architect who accepts direction of a project they did not author assumes liability for any omissions or defects in that project, with right of recourse against the original proyectista.

How are architect fees structured in Spain?

Architect fees in Spain (honorarios) are calculated against the presupuesto de ejecucion material (PEM), the construction budget excluding VAT and overheads. The Colegio de Arquitectos publishes an annually updated recommended fee scale (baremo de honorarios) that serves as the professional reference for fee negotiations.

For a full new-build residential project including design, proyecto redaction, direccion de obra and project management, fees typically run approximately 4 to 8 per cent of PEM depending on complexity, scale and the level of service. IVA at 21 per cent is added to all professional fees. Renovation projects may attract different fee structures, and the visado colegial carries a separate administrative charge set by each regional college.

The fee is usually split across phases: an initial design and project redaction portion (paid on delivery of the visado proyecto), and a supervision portion (paid monthly or in stage tranches during construction). Buyers commissioning only an informe pericial or informe tecnico should expect a fixed fee per assignment rather than a percentage, reflecting the discrete scope of the work.

When does a buyer need an architect versus an arquitecto tecnico?

The distinction between the architect and the arquitecto tecnico maps to the type of work involved:

• New build or structural renovation (obra mayor): requires a full architect (proyectista and director de obra under LOE articles 10 and 12) plus an arquitecto tecnico (director de la ejecucion under article 13).
• Minor renovation (obra menor): may require only an arquitecto tecnico to issue a declaracion responsable or minor works certificate, without a full architect’s project.
• Pre-purchase structural survey: an informe tecnico by an architect or arquitecto tecnico, not a full project.
• Construction defect litigation: an informe pericial by a college-registered architect.

For foreign buyers, the practical sequence is: engage an architect to produce the proyecto de obra before approaching the town hall for a licencia de obra mayor, then have the same architect (or their practice) direct the obra alongside an arquitecto tecnico. After completion, the certificado final de obra and licencia de primera ocupacion close the construction phase. If disputes arise later, a separate architect acting as perito prepares the evidentiary report.

Understanding these role boundaries helps buyers avoid the common mistake of treating the Spanish architect as optional or interchangeable with a builder. The LOE framework makes the architect a statutory agent whose involvement is a legal prerequisite, not a professional preference.

This guide is general information, not legal or tax advice. Rules change and individual circumstances differ. Verify current requirements with an independent lawyer (abogado) or tax advisor (gestor/asesor fiscal) before acting.