Real Estate Development Project in Tunisia Expands the Role of Architecture as Second Nature, Balancing the Relationship Between Humans, Nature and Culture

The real estate development project "Domaine de l'Anse Sauvage" conducted by Philippe Barriere Collective is located northeast of Tunis on the Gammarth coast, on a hillside overlooking the Baie des Singes. This project is part of a process that aims to expand the role of architecture so that spaces, in relation to the exterior, become “second nature.”


Building A - Typical Bloc -NNE façade - (Direct view on the bay), Photo credit: image Philippe Barriere Collective (Mamary Coulibaly, Farouk Dine, Mohamed Yahmadi, Philippe Barriere)

This 30% re-qualification of the project makes it possible to compensate for existing deficits in the surrounding ecosystem, and to prevent aggravations due to its construction. By becoming a medium for new relationships with nature, architecture becomes the guarantor of its balance and integrity within the environment that has distorted it.


Building B (NNE Façade) - Private roof + solar collector), Photo credit: image Philippe Barriere Collective (Mamary Coulibaly, Farouk Dine, Mohamed Yahmadi, Philippe Barriere)

The irreversible destruction perpetrated around the project site inspired a maximization of green space to bolster the ecosystem and compensate for what had been irreparably lost. This process required implementation of a strategy for multiple types of spaces, each fulfilling a particular function within the relationship, thus becoming an annex, addition, or extension depending on the case. These are, for example, the ancillary spaces housing nurseries, Winter Garden (the NNE facade), as well as annexes where more specialized native species are cultivated: loggia or planted roofs, private gardens, etc., which provide supplementary nature.


Ganaria (south façade, double skin serving as a bioclimatic buffer space with moucharabieh), Photo credit: image Philippe Barriere Collective (Mamary Coulibaly, Farouk Dine, Mohamed Yahmadi)

Project presentation

To better preserve this unique green enclave, 70% of the estate remains vegetated (54% converted into a botanical garden, and 16% into private gardens). The remaining 30% accommodates 164 housing units (50% of their roof areas are green). The botanical garden is home to endangered native species, as well as a great diversity of “dry plants” to fix the soil, store moisture, and restore biodiversity.


Building A - Typical Bloc -NNE façade - (Direct view on the bay), Photo credit: image Philippe Barriere Collective (Mamary Coulibaly, Farouk Dine, Mohamed Yahmadi, Philippe Barriere)

Refusal to complete the blocking of the bay with concrete inspired an open architecture, composed of porous layers with housed living spaces in between, ensuring continuity and exchanges with the outside. These layers provide fluidity that invites users to project themselves into an all-encompasing environment (interior + botanical garden). Therefore, the botanical garden is no longer just a place of passage, but rather a living space. Practices generated by this architecture allow an open lifestyle model, which encourages a collective approach to safeguarding the environment.


Building A - Typical Bloc -NNE façade - (Direct view on the bay), Photo credit: image Philippe Barriere Collective (Mamary Coulibaly, Farouk Dine, Mohamed Yahmadi, Philippe Barriere)

To achieve this, the botanical garden and architecture are inseparable as part of a project design conceived as an interior-exterior relationship. The design echoes the Byzantine and Islamic Persian gardens that made it possible to create places of social gathering, mediation, and amplification in a symbiotic environment that is “second nature.” The “interior-exterior” limit no longer serves as a closure, but rather as a spatial unit, both as the “subject” of the different functions it fulfills, and the attributes of the architecture that it defines. The typologies and their different uses vary according to the cardinal orientation and levels: - Winter Garden (NÉ facade, with accordion patio doors, serving as a nursery for the garden) - Ganaria (South facade, serving as a bioclimatic buffer space with moucharabieh) - living loggia terrace (with exterior double rail curtain) - planted roof garden (with species that complement those in the garden) - double skin loggia - individual, habitable garden (allowing customizing and accommodating species requiring more maintenance).


Living with the Botanical Garden: connection and interpedence with nature (continuity between botanical garden and private garden), Photo credit: Philippe Barriere Collective (Mamary Coulibaly, Farouk Dine, Mohamed Yahmadi)

Master plan

The master plan plays an important role in balancing the relationship between humans, nature, and culture, which it is attempting to redefine. The layout of the buildings frees up views with 3 main orientations: the open sea, the Forest of Gammarth, and the Marina, with 75% of the accommodations having direct sea views. The private rooftop gardens offer triple views overlooking the bay, its horizon, and the Forest.


Building A (NNE facade), Photo credit: Philippe Barriere Collective (Mamary Coulibaly, Farouk Dine, Mohamed Yahmadi, Philippe Barriere)

Double skin

In biology, specification is the phenomenon by which tissues transform to specialize organs and single out a species. The space between the exterior facade and the interior facade constitutes a double skin that generates functional differentiators according to the levels, cardinal orientations, location within the site, the slope of the land, and the perspectives on the panorama.

The double skin allows buildings to respond to external climatic contingencies (environment, seasons, prevailing winds, humidity, etc.), and to the changing necessities of interior needs. It acts as an operating organ:

  • A bioclimatic function that tempers meteorological fluctuations.
  • Spatial continuities with the displacement of the center of gravity of the home (living room) outwards.
  • Vegetal continuities between the outdoor garden and the interior of the house, thanks to the Winter Garden (which can also be used as a nursery).

- A widening of the interior visual field by making it coincide with the totality of the panorama.


Link between botanical garden, swimming pool, private garden Living and the interior of the Duplex. Photo credit: image Philippe Barriere Collective (Mamary Coulibaly, Farouk Dine, Mohamed Yahmadi, Philippe Barriere)

Botanical Garden

The botanical garden is a reserve of wild plants, where native species are preserved in their natural environments. It contributes to the reconstruction of the original vegetation and the biotope altered by buildings that have been demolished. The reintroduced species participate in the site's adaptation to climate change (garden without water), standing up to prevailing winds (Cypress) and helping to slow down soil erosion, while conserving soil moisture. This type of planting requires maintenance at least 4 times per year. This garden can serve as a laboratory to explore methods for preserving other threatened ecosystems.


Botanical Garden, Photo credit: Philippe Barriere Collective (Philippe Barriere)

About Philippe Barriere Collective (PB+Co)

Challenging both theory and practice, Philippe Barriere Collective has developed a forward-thinking expertise that addresses suburbanization (i.e. ParkUrbia), the Interstate Highway System (i.e. Infrastructure Architecture), and social and humanitarian issues such as homelessness, refugee camps, and health crises. More recently it has developed the concept of Hybrid Architecture (i.e High-Low Tech) in the Maghreb.

Philippe Barriere is an architect (DPLG), urban planner (DIUP), critic, and architectural historian. A graduate of Ecole des Beaux-arts in Paris (UP1), he received a scholarship to study in the graduate program of Cranbrook and Cornell University. He has a master's degree from the Paris Urban Planning Institute, a Doctorate in Art History from Pantheon-Sorbonne University, and a Master in Architecture from Pratt Institute (New York). In addition to conducting professional activities around the world (France, Venezuela, French West Indies, Saudi Arabia, United States, and Tunisia), he has participated in a number of voluntary actions for the United Nations (UNWRA in Jordan for Palestine), as well as non-governmental organizations in Kenya (CTC), Haiti (Haiti Delaware Alliance Foundation), and Tunisia (Acacias for All).  In recognition of his contributions, he was appointed Chevalier dans l'Ordre des Arts et des Lettres by the French Ministry of Culture in 2006. Many of his projects have been published, and have received awards and nominations.