Torre IRSA, Office building in Retiro district, Buenos Aires, Argentina.

Torre IRSA is an office building with 24 floors and a distinctive pentagonal shape located on Maipú street in the Retiro neighborhood. The structure features suspended floor levels supported by a triangular core, creating its unusual geometric form.

Torre IRSA was designed by architect Mario Bigongiari and first known as Torre Pirelli. Its suspended-floor structure, with a triangular core inside a pentagonal base, left levels 12 and 23 as structural floors. The building later became the headquarters of the IRSA real-estate group led by Eduardo Elsztain.

The exhibition hall occupies the first floor, not the ground floor; the ground floor holds the reception and parking. Since 2010 a Starbucks branch has occupied the ground floor, and the tower houses the IRSA group headquarters led by Eduardo Elsztain, plus the Durrie and Allende & Brea law firms.

The tower has two independent banks of two lifts each, running at 210 metres per minute, plus a fifth lift that joins either bank at peak hours. The ground floor holds reception and parking, and the 24th floor is the machine room. The ground floor has housed a Starbucks branch since 2010.

The rooftop helipad was not the only unusual feature: the tower has two independent elevator banks of two cars each running at 210 metres per minute, plus a fifth car that can join either bank at peak hours. The core is triangular inside a pentagonal base.