Rehabilitating Lisbon: Preserving History, Shaping the Future

Lisbon is a city built in layers. From medieval walls to the palaces destroyed by the 1755 earthquake, from Pombaline reconstruction to 19th-century residential buildings and 20th-century architecture, each period has left its mark, often with different historical layers overlapping within the same building.

Rehabilitating a building in this city therefore means more than restoring materials or upgrading installations. It means deciding what should remain, what can change and how to introduce contemporary requirements for safety, comfort and use without erasing what makes each building, and each place, unique.

In this article, we explore the principles that guide MJARC Architects in a building rehabilitation project in Lisbon and show how they were applied in a specific case: a building in Chiado constructed over the medieval Fernandina Wall.

Building Rehabilitation in Lisbon: Understanding the Existing Architectural Heritage

Much of Lisbon’s building stock predates contemporary construction regulations. According to Lisbon’s Urban Rehabilitation Strategy 2011–2024, based on the 2001 Census, approximately 90% of the city’s buildings were constructed before 1983, and more than 60% did not have reinforced concrete structures. The average age of the building stock exceeded 50 years, around 20 years above the national average.

It is therefore unsurprising that rehabilitation has played a major role in construction activity. Between 2005 and 2010, Lisbon City Council issued approximately four times as many permits for rehabilitation works as for new construction. Between 2011 and 2019, between 89% and 92% of completed buildings in the municipality resulted from extension, alteration or reconstruction works.

Today, the question is not whether buildings should be rehabilitated, but how. A rehabilitation project can extend the life and meaning of a building, or become a superficial transformation that erases its history. The difference lies in the criteria guiding the intervention.

Assessing Historic Buildings: Understanding Before Designing

The first step in any rehabilitation project is to understand the existing building. Observing its façades and interiors is important, but it cannot replace a rigorous assessment.

The construction date provides an initial indication. Lisbon City Council identifies several key periods in the city’s building stock: pre-Pombaline, Pombaline and “gaioleiro” buildings up to 1900; mixed timber, iron and concrete structures between 1900 and 1940; the introduction of the General Regulation for Urban Buildings (RGEU) in 1951; and the structural regulations of 1983, which introduced requirements to consider seismic actions in structural design.

However, every building has its own history, shaped by successive periods, alterations and additional floors. Understanding it requires a multidisciplinary assessment:

• Architectural survey: accurate documentation of every floor, recording the current condition of the building and the alterations made over time.
• Historical research: a historical and artistic study of the building and its surroundings, supported by archives, historical maps and municipal building records.
• Archaeology: investigations of the ground and walls to reveal what the existing construction may conceal.
• Structure and materials: assessment of load-bearing walls, floors, roofs and foundations, as well as defects such as dampness, cracking and material deterioration.
• Conservation and restoration: identification and assessment of significant architectural elements, including stonework, tiles, plasterwork and joinery.

Only through this understanding is it possible to determine what should remain, what needs to be corrected and where a new intervention can add value.

Urban Rehabilitation in Lisbon: Planning Regulations, Heritage and Constraints

A building is part of a street, an urban block and a wider cityscape. In Lisbon, many of these urban environments are the result of precise planning principles.

In Chiado, for example, the Pombaline reconstruction plan of 1758 proposed buildings for the district’s prestigious streets that differed from those in Baixa, incorporating entrances and balconies that recalled the palaces that existed before the earthquake. Understanding these principles helps determine how to intervene in façades, roofs and building heights without disrupting the character of the urban ensemble.

Understanding the place also requires examining its planning framework. Lisbon’s Municipal Master Plan (Plano Diretor Municipal, or PDM) establishes rules governing land occupation, use and transformation, complemented by the Municipal Regulation on Urbanisation and Building (RMUEL) and, where applicable, other municipal plans.

In historic areas, this assessment must also consider the Municipal Heritage Inventory, listed buildings and their respective protection zones, where alterations to façades, roofs, openings or building volumes may be subject to specific requirements.

Lisbon also has an extensive Urban Rehabilitation Area (Área de Reabilitação Urbana, or ARU), covering much of its consolidated urban fabric. These areas are established under the Legal Framework for Urban Rehabilitation (RJRU), approved by Decree-Law No. 307/2009.

Being located within an ARU may be relevant to the project’s regulatory framework and eligibility for incentives, but does not automatically guarantee tax benefits. To understand this distinction, read our article on ARU, ORU and tax incentives for urban rehabilitation.

Archaeology and Heritage: What Lies Beneath Also Matters

In historic Lisbon, the ground and even the walls themselves may preserve traces of centuries of occupation.

The PDM identifies areas of archaeological interest where works involving excavation, demolition or intervention in existing walls may require preliminary archaeological investigations and archaeological monitoring during construction.

Addressing these requirements at an early stage allows archaeological findings to be integrated into the design, rather than discovered unexpectedly once construction is underway.

Architectural Heritage Conservation: What to Preserve and What to Transform

Not every element of a historic building has the same significance. The composition of its façade, original structure, staircases, decorative features and spatial organisation each tell part of its story.

Preservation does not mean freezing a building in time. It means identifying the elements that define its identity and ensuring that they remain legible after the intervention.

When transformation is unavoidable, because a building must meet new requirements or accommodate a new use, the changes should be properly documented.

An accurate survey of the building before construction is also a record for the history of the city.

The same level of care applies to new interventions. An extension, a new roof or the alteration of openings becomes more coherent when informed by the architectural strategies developed by the building and its surroundings over time.

Rehabilitating Historic Buildings: Safety, Comfort and Energy Efficiency

A rehabilitated building must be safe, comfortable and functional. The challenge is to introduce these requirements without destroying the qualities that the project seeks to preserve:

• Seismic safety: assessment of the building’s vulnerability and, where necessary, structural strengthening compatible with the existing construction system.
• Fire safety: compartmentation, escape routes and material performance, particularly relevant in buildings with timber structures.
• Comfort and energy efficiency: insulation, ventilation, natural lighting and thermal performance, without compromising valuable façades and materials.
• Accessibility: solutions that improve access and circulation while responding to the limitations of the existing building.

The legal framework applicable to building rehabilitation, established by Decree-Law No. 95/2019, recognises these specific conditions. It is based on principles such as protecting and enhancing the existing building and progressively improving its performance in a proportionate way, rather than requiring an older building to meet exactly the same conditions as new construction.

Seismic Vulnerability Assessment in Building Rehabilitation

Seismic safety deserves particular attention, as Lisbon is located in a region with significant seismic risk.

A seismic vulnerability assessment report is required for certain extension, alteration or reconstruction works, including, for example, interventions that change a building’s structural behaviour, affect more than 25% of its gross construction area or involve structures showing clear signs of deterioration.

When the assessment concludes that the building does not meet the required safety levels, a seismic strengthening project becomes mandatory.

Change of Use in Historic Buildings: Adapting Without Erasing Identity

Many buildings deteriorate because they have lost the function for which they were originally designed. Finding a new use is often essential to ensuring their preservation.

However, the new use should adapt to the building, rather than the other way around. A compatible programme respects the existing structure, spatial organisation and character of the place.

In a city with such a rich historical fabric, this compatibility can even represent a form of continuity: a new programme that reconnects with a use once present in the same location.

This approach is also explored in MJARC’s reflection on hospitality, rehabilitation and adaptive reuse in hotel architecture, where transforming existing buildings can create new experiences without erasing their memory.

Building Rehabilitation Permits in Lisbon: Procedures and Legal Requirements

Not all rehabilitation works are subject to the same administrative procedures.

Portugal’s Legal Framework for Urbanisation and Building (Regime Jurídico da Urbanização e Edificação, or RJUE) distinguishes between operations exempt from prior control, those subject to prior notification and those requiring a building permit.

The Urban Planning Simplification Reform (Simplex Urbanístico) of 2024 and the revision approved by Decree-Law No. 108/2026, in force since 1 October 2026, seek to simplify and accelerate these procedures.

Prior notification becomes the standard procedure when urban planning parameters have already been established, while the Prior Information Request (Pedido de Informação Prévia, or PIP) takes on greater importance. However, exemption from a building permit does not remove the obligation to comply with technical, heritage and planning regulations.

A change of use combined with an extension, particularly in a historic area, often involves consultation with several authorities and demanding documentation requirements.

In these operations, the quality of the initial assessment and the coordination of the process can make a significant difference.

For further information on procedures and timelines, read our article How Long Does It Take to Obtain a Building Permit in Portugal?.

When there are uncertainties regarding the planning feasibility of an intervention, a Prior Information Request (PIP) can help clarify the conditions applicable to the project before proceeding.

Hotel Chiado: A Historic Building Rehabilitation Project in Lisbon

On Rua António Maria Cardoso, in Chiado, MJARC Architects obtained approval for a change-of-use and extension project involving a 19th-century building, with the aim of converting it into a hotel.

The extension includes a new basement level and the redesign of the roof. When the project was developed in 2013, the building was the only abandoned and deteriorated property on the street, surrounded by restored buildings and Álvaro Siza’s Terraços de Bragança development.

The Hotel Chiado rehabilitation project demonstrates how historical research, archaeology and architecture can guide the transformation of a heritage building.

Historical Assessment: Four Periods Within a Single Building

The archaeological investigation, conducted in two phases, revealed that the building conceals a history extending far beyond what its façade suggests:

• A section of the Fernandina Wall, built under King Ferdinand I in 1373, incorporated into the rear façade.
• Vaulted rooms dating from before the 1755 earthquake, probably belonging to the former Palace of the Marquis of Valença. One appears to have been a stable, as indicated by iron rings set into the walls and rounded door jambs designed to allow carts to pass through.
• The 19th-century building as we know it today, altered throughout the 20th century and extended with an attic storey in 1956.

Chiado Architecture: A Prestigious 19th-Century Rental Building

The historical and artistic study prepared for the project identifies the building as a “prestigious rental building”: a residential property that takes advantage of the variations permitted by the 1758 plan for Chiado’s prestigious streets, with a pronounced entrance-and-balcony axis and two principal floors.

It also incorporates characteristic 19th-century elements, including a balustraded parapet and rusticated stonework at ground level.

The detailed survey carried out by MJARC suggests that the building originally contained two separate dwellings, with independent entrances and staircases: the main limestone staircase serving the first floor and a secondary staircase providing access to the second.

Architectural Intervention: Preserving the Façade and Adapting the Spaces

The project brought together archaeology, art history, conservation and restoration, alongside the other technical disciplines, from its earliest stages.

This knowledge informed the main architectural decisions:

• Main façade: preserved in its entirety. The only alteration concerns the attic level, where the existing three openings are replaced by a regular sequence of nine openings along the parapet. The slight increase in building height establishes a more harmonious relationship with the roofline of Terraços de Bragança and reduces the height difference with the neighbouring building.
• Rear façade: continuous balconies on the upper floors and a more regular attic composition, following an approach consistent with the ways existing façades were enhanced during the 18th and 19th centuries.
• Basement and medieval wall: manual archaeological excavation during earthworks, together with archaeological monitoring of demolition and structural reinforcement works near the wall and the pre-earthquake structures.
• Building memory: the accurate survey of every floor documents the building’s condition and the transformations it has undergone. The historical study itself recommended that this documentation be archived by the City Council as a reference record.

Adaptive Reuse: A New Hotel Rooted in Chiado’s History

Converting the building into a hotel is not disconnected from the history of this street.

In 1845, just a short distance away, on the grounds of the former Palace of the Dukes of Bragança, the Hospedaria Bragança opened as one of the major hotels of 19th-century Lisbon.

The historical study concluded that the project would have a positive impact: preventing the continued deterioration of a building that disrupted the urban ensemble, preserving its façade and reconnecting the street with a hospitality tradition already present in its past.

Beyond Lisbon, projects such as Green View Tower, in Covilhã, which aims to preserve more than 65% of the original structure, and Riverside Condominium, in Santa Comba Dão, which reuses more than 90% of the existing structure, follow the same principles: understanding existing conditions, preserving elements of lasting value and introducing solutions capable of meeting contemporary requirements.

Architectural Rehabilitation in Lisbon: Designing the Future from What Remains

Every historic building is a document of the city. Rehabilitating it requires technical knowledge, architectural sensitivity and a careful understanding of the place, including both what is visible and what remains hidden.

The principles guiding our work are simple to express but demanding to implement: understand before designing, interpret the place, preserve what matters, respond to contemporary requirements and identify a compatible use.

Ultimately, every intervention should begin with one question: what can this building continue to offer the city and those who will use it?

At MJARC Architects, we develop architecture and rehabilitation projects through this perspective, bringing together the preservation of existing buildings and new opportunities for their use.

Are you considering the rehabilitation of a building or apartment in Lisbon?

Tell us about your project and discover how we can help transform the potential of your property into a coherent architectural proposal.

Frequently Asked Questions About Building Rehabilitation in Lisbon

Is a seismic assessment mandatory for building rehabilitation in Lisbon?

It depends on the proposed works. A seismic vulnerability assessment report is required for certain extension, alteration or reconstruction works, including those that change the building’s structural behaviour, affect more than 25% of its gross construction area or involve structures showing clear signs of deterioration.

The age of the building alone is not the determining criterion.

Do I need an archaeologist for construction works in Lisbon’s historic centre?

In many areas of the city, yes, particularly when works involve excavation, demolition or intervention in historic walls.

The PDM identifies areas of archaeological interest, and the required works may include preliminary investigations and archaeological monitoring during construction.

Is it possible to change the use or extend a historic building in Lisbon?

It may be possible, but this depends on the parameters established by the PDM, the building’s heritage status and the constraints affecting the site.

A thorough assessment of the existing building and, in many cases, a Prior Information Request are the most appropriate starting points.

Does being located within an Urban Rehabilitation Area automatically provide tax benefits?

No. Being located within an ARU may provide access to incentives, but eligibility depends on the type of intervention, compliance with the relevant requirements and the tax legislation in force.

Sources and Legislation

Information consulted in October 2026.

Lisbon City Council. Lisbon Urban Rehabilitation Strategy 2011–2024.

Figueiredo, N. G. O. (2022). Dinâmicas de Crescimento Urbano na Região de Lisboa e Vale do Tejo 2011–2021. Master’s internship report, Spatial Planning and Urbanism, University of Lisbon.

Lisbon City Council. Lisbon Municipal Master Plan (PDM), regulations and land-use and constraints maps.

Lisbon Municipal Master Plan

Lisbon City Council. Municipal Regulation on Urbanisation and Building (RMUEL), published through Notice No. 16520/2021, without prejudice to subsequent amendments.

Complementary Urban Planning Regulations

Lisbon City Council. Lisbon Urban Rehabilitation Area, delimitation and extension of validity.

Lisbon Urban Rehabilitation Area

Decree-Law No. 307/2009 of 23 October. Legal Framework for Urban Rehabilitation (RJRU), as amended.

Decree-Law No. 95/2019 of 18 July. Legal framework applicable to the rehabilitation of buildings and individual building units.

Ordinance No. 302/2019 of 12 September. Conditions under which extension, alteration or reconstruction works require a seismic vulnerability assessment.

Decree-Law No. 555/99 of 16 December. Legal Framework for Urbanisation and Building (RJUE), as amended.

Consolidated Legislation — RJUE

Decree-Law No. 108/2026 of 29 May. Revision of the urban planning and building control framework, including amendments to the RJUE, RJRU and RGEU, with entry into force postponed until 1 October 2026 by Decree-Law No. 155-B/2026.

Decree-Law No. 108/2026

Leal, Joana Cunha (2013). Relatório de caracterização da pré-existência: Rua António Maria Cardoso n.º 9-13, Lisboa. Institute of Art History, Faculty of Social Sciences and Humanities, Universidade Nova de Lisboa.

Neoépica, Lda. (2013). Relatório dos trabalhos arqueológicos realizados na Rua António Maria Cardoso n.º 9-13, Lisboa, 2.ª fase.

Note: The regulatory framework applicable to each project depends on the characteristics of the building, current legislation and the specific constraints of its location. This article does not replace an individual technical and urban planning assessment.