ARCHITECTURE

Aluminium spiral

On a mission to make San Francisco a city filled with futuristic and unusual buildings, that not only save urban space but are also sustainable and high-tech, Studio Gang has recently finalised its newest architectural creation – the 'Mira Tower'. A remarkable building featuring an aluminium façade, inspired by aerospace technology.
17 November, 2020
According to the studio, "The design reflects the huge demand for housing in San Francisco and offers new opportunities to be sustainability, all while reinterpreting the city's architectural traditions."
The building was designed to both incorporate and innovate the traditional bay window, a recognisable characteristic of the city's more traditional residential properties. The studio's contemporary twist on the bay window extends the height of the tower, allowing in swathes of natural light and providing inhabitants with a breathtaking vantage point. This aspect of the architecture was central to the entirety of the building's distinctive design and was carefully planned with both the structure's energy performance and its impact as a feat of structural engineering in mind.
Images: Studio Gang
The ornate, spiraling tower stands almost 130 meters tall, with its impressionist appearance cleverly created through the vertical repetition of the 11 floor structure. This unique design idea combines a beautiful collection of misaligned bay windows, creating a visual illusion that the building is twisting as it ascends from ground-level.

In an effort be as sustainable as possible the architects chose aluminium and glass to be the primary materials for the tower's façade. The final design, saw a total of 8239 aluminium and glass panels being used to create a fragmented impression that was in keeping with the structure's spiral shape.

Images:Dezeen
The building's unique form also bears a functional purpose, as it is able to withstand the wind that is both naturally occurring and that is generated by the ascensional draughts produced as a result of the tower's shape. The façade was in fact designed by an Italian company, using aerospace technology to prevent the strong air currents in the Bay area, from producing too much noise, damaging the tower's exterior or compromising the stability of the window frames over time.

According to the Permasteelisa Group website: "The façade consists of insulated, horizontally configured, 3-dimensional spandrel units clad in white aluminium panels. Panels that have been finished with liquid fluoropolymer high performance coating and then applied with a technique derived from aerospace technology, specifically adapted for this project due to the extraordinary dimensions of the parts." The units clad with the aluminium were then joined to the building's concrete interior using purpose-built steel and aluminium arms with the bay window units situated vertically between the panels. The article continues to describe that, "this configuration achieved the required soffit and coping geometry with a coherent approach, while minimizing the overall facade weight." Given the design's load restrictions, aluminium remains the perfect material for the façade panels due to its lightweight characteristics.
Images: Dezeen
The tower's spiral design was created with 20 angled bay units consistently alternating in soffit and coping systems. The units are repeated in interchanging left and right angles on each floor, generating the building's impressive twisting appearance.

The high-performance façade, built with mostly sustainable materials, combined the tower's advanced VRF cooling system has meant the building has achieved the ambitious California Title 24 energy standards. In addition, the Mira Tower's pioneering graywater harvesting system, green roof, and high-efficiency fixtures, mean the building has been awarded the project LEED (Leadership in Energy and Environmental Design) Gold Certification. This award is an internationally recognised green building certification system, providing third-party verification that a building has been designed and built using strategies aimed at improving performance across all metrics in energy and environmental conscious design.
Banner image: Dezeen