Spherical House in São Paulo Opens for ABERTO5 Exhibition After Decades as Private Residence

Rare Public Access to Experimental Brazilian Architecture

A radical spherical house in São Paulo opened to the public for ABERTO5 from March 8 to May 31, 2026. The futuristic structure hosts the fifth edition of ABERTO, a Brazilian architecture and art exhibition platform. Casa Bola, built between 1974 and 1979, represents one of Brazil’s most experimental domestic spaces. The eight-meter-diameter sphere challenges conventional housing paradigms.

Hand-Built Prototype Defies Traditional Design

Architect Eduardo Longo constructed this spherical house entirely by hand using ferrocement. Moreover, he molded the material over a complex mesh of recycled steel tubes. The construction method integrates walls, furniture, lighting, and sanitary elements into one continuous organic form. Additionally, the dwelling sits suspended above a rooftop slab in the Itaim Bibi district. The project marked a significant departure from angular geometry toward spherical systems during the 1970s.

This experimental vocabulary contrasted sharply with the transparency and structural rationalism of Brazilian modernist architecture at that time. The exhibition brings renewed public attention to Eduardo Longo’s experimental dwelling.

Exhibition Transforms Private Architecture Into Public Platform

According to the organizer, ABERTO5 presented around 60 art and design works by more than 50 Brazilian and international artists. Furthermore, the exhibition spans 1,000 square meters including the terrace and spherical house. Many contemporary works respond directly to the radical character of this habitable sculpture. The curatorial framework positions the spherical house as a setting for artistic experimentation.

Platform Continues Modernist Architecture Series

This edition continues a significant pattern of activating historic private residences. The inaugural 2022 edition took place in the only private residence designed by Oscar Niemeyer in São Paulo. Subsequently, the 2023 edition featured a house by Vilanova Artigas. The 2024 edition opened two modernist homes to the public for the first time. Additionally, the 2025 edition marked the first international presentation at Le Corbusier’s Maison La Roche in Paris.

The platform reactivates buildings of historical significance by transforming them into settings for contemporary art and design dialogue.

Will this spherical house inspire renewed interest in experimental housing prototypes from the radical architecture movement?

A Quick Architectural Snapshot

The spherical house measures eight meters in diameter and sits suspended above a rooftop in São Paulo’s Pinheiros subprefecture. Ferrocement molded over recycled steel tubes creates the continuous structural shell. The dwelling integrates all functional elements into its organic form. Construction occurred entirely by hand between 1974 and 1979, establishing a prototype for spherical housing systems.

✦ ArchUp Editorial Insight

Opening a private experimental dwelling for an exhibition allows visitors to encounter its unusual spatial organization directly. This is an opportunity for architectural interpretation; the available evidence does not establish why spherical housing was not adopted more widely. Claims about procurement, insurance or the art market as exclusive causes would require separate research.

Source: ABERTO5 official exhibition page. The organizer lists the public dates as 8 March–31 May 2026.