On a hill above Portisco, Sardinia (on the Costa Esmeralda), a group of (partially underground) villas designed 40 years ago were given a new lease of life through a comprehensive renovation, completed in September 2019. Penetron crystalline technology enhanced the durability and lifespan of the existing concrete structures.
“Today, the modern architecture along the breathtaking coastline of the Costa Esmeralda in northeastern Sardinia is barely remembered,” explains Enricomaria Brac, Managing Director of Penetron Italia. “But in the 1960s and ‘70s, the creativity of a handful of architects from Turin, Italy, led to “New Brutalist” designs. This international architectural style, which took advantage of the flexibility and strength of reinforced concrete, created geometric forms with lots of exposed concrete.”
Ferdinando Fagnola and Gianni Francione were two of the architects who designed the group of Sardinian villas in 1975. Embedded in a promontory above the village of Portisco, the architects integrated – or even camouflaged – the geometric architectural elements of the villas in the landscape in an effort to preserve the stunning natural setting of red rocks and bushland facing a deep turquoise Mediterranean Sea.
Restoring a Brutalist Design
The design originally comprised five houses; however, only one of the villas was finished at the time according to the architects’ design. The other structures were built later and diverged in ways very remote from the Brutalist purity, which had been envisioned by the duo from Turin. In 2011, new owners were able to purchase three of the villas and drew up plans to renovate, restore and enlarge the buildings.
“Amazingly enough, the owners actually turned to the original architects to guide the restoration,” adds Enricomaria Brac. “Only Fagnola was available, who brought PAT, an architectural design group of young Turin architects, into the project.”
Bringing a 20th Century Design Up to Date
The original layout of large wedges of raw concrete driven into the ground had created partially underground structures, which contributed to a stable interior climate. However, modern upgrades were needed: insulation for the concrete shells, “green” insulated roofs, a central heating system, and an all-inclusive spa that included a sauna, outdoor swimming pool, hot tub (with its own waterfall), massage room with a Turkish bath and showers, and a dining area.
“With the spa housed in one of the villas, all the below-grade concrete structures and elements exposed to the marine environment – including the 20-m infinity pool – were treated with the Penetron System,” says Enricomaria Brac. “The existing concrete was waterproofed with an application of PENETRON.”
Protecting Exposed Concrete
PENETRON is a surface-applied, crystalline waterproofing material that penetrates deeply into the structure. A chemical reaction is unleashed in the presence of any moisture in the concrete to fill the micro-cracks, pores and capillaries with an insoluble crystalline formation. This formation prevents water and water-borne chemicals from entering the concrete, ensuring a vastly enhanced durability for the concrete matrix. The new concrete elements added for the spa were treated in the batching phase with PENETRON ADMIX, an integral crystalline admixture that provides comprehensive protection against concrete deterioration caused by exposure to the elements (chemical attack, freeze-thaw cycles and corrosion).
“Having fallen out of favor since the 1980s, buildings in the Brutalist style are now making a comeback,” adds Enricomaria Brac. “When I look at the renovated villas on the Costa Esmeralda, I can understand how people appreciate the marvelous graphic quality of the design and the raw concrete surfaces.”