This past year, after observing the deterioration the 115-foot-tall structure had endured over the last 25 years, a group of renowned companies and local organizations that handled the creation of the Tower joined forces to complete a full restoration. All of the groups, which donated their time and materials, worked collaboratively to restore the Tower back to its original luster, just in time for the Expo 2015, which was held in Milan.

“The goal of the project was to recolor a part of Milan, giving creativity and life to an artifact that was gray and degraded, and to also stimulate the forces of the artistic and the emotional world of design and fashion,” said Francesco Roggero, executive associate of Studio Original Designers 6R5 Network in Milan, Italy, the architectural firm that has been involved with the project since its inception, which also led the design of the recent restoration. “The Rainbow Tower aims to encourage a process of ideas about coloring, between light and shadow, and which they are perceived. We wanted to relay the colors that interpret the boundaries of being and the mysteries of dreams and egos, chasing graphics and flashes of memory in people’s imaginations, as well as the harmonies of the nuances that surround us and delineate spaces known and unknown.”

The creation of the Rainbow Tower

When the Tower was originally renovated in 1990, Roggero and his team employed more than 100,000 ceramic tiles in a 10- x 10-cm format from Marazzi’s Sistem C collection. Utilizing 14 different colors from the collection — ranging from brighter tones of red and yellow to darker shades such as navy and black — is where the name “Rainbow Tower” was ultimately derived from. The design team and other parties involved covered the 1,000 square meters of bare exterior, making the Tower a central skyscraper in Milan.

“It aims to be a totem of color that speaks to our five senses,” said Roggero, who explained how the idea behind the project was to highlight the structure of the Tower, which embraces a circular and concave shape that’s divided into 22 “faces” and interrupted by an equal number of ribs in relief. “It’s a recognizable element for the city to remind visitors of the leadership of Milan in design and fashion, and the dynamism of its people and artisans.”

The structure has withstood significant wear-and-tear during the past 25 years — from detached, missing tiles to iron- and dust-infested surfaces, and even graffiti-ridden areas.

To fix these imperfections and return the Tower to its original splendor, Roggero and a trio of architects from Studio Original Designers 6R5 Network — Albino Pozzi, Rita Alfano Roggero and Kiyoto Ishimoto — collaborated with nearly 35 other individuals from Marazzi, Bazzea, Mapei, Condor S.p.A. and Fila Surface Care Solutions. Additionally, a group of employees from the public works and site amenities Department of the Milan City County and Italian state railway authorities were also involved to help bring this project to life.

Restoring the Tower

Bazzea, a construction company located in Vigevano, Pavia, Lombardy, Italy, was in charge of the technical management of the construction site as well as the installation. A team of six people from the company was assembled, which began the restoration with the initial cleaning of the Tower’s 1,000 square meters of surface area that had been tarnished by fine dust at the top and metals — in particular, iron — at the bottom. Products from Fila Surface Care Solutions — based in San Martino di Lupari, Padova, Veneto, Italy — were responsible for the cleaning and protection of the external facade, restoring its color and brightness to their original beauty. The glazed ceramic tiles, ruined by rust and impregnated by smog, were treated with Fila PhZero, a descaling acid concentrate that effectively removes dirt and is ideal for vertical walls thanks to its viscous consistency.

After handling the oxidation issues, Bazzea’s workers focused on removing the graffiti that defaced the lower walls of the Tower. A powerful anti-graffiti cleaner, Fila No Paint Star, was the perfect solution for the removal of the graffiti. To effectively protect the tiles, installers then applied a layer of FilaStop Dirt, a dirt-repellent and anti-graffiti protector for textured and unglazed porcelain tiles that forms an invisible barrier on the surface, thus preventing the accumulation of dirt for easier and quicker cleaning.

After the surface work was completed, the installers began replacing all of the missing, detached and damaged tiles around the Tower, which took about 15 days, according to Roggero. Approximately 3,000 tiles needed to be replaced, which were supplied directly from Marazzi Group in Sassuolo, Modena, Emilia-Romagna, Italy. Marazzi supplied the same color range of 10- x 10-cm format ceramic tiles from its Sistem C collection, as in 1990 for the original renovation.

“The concept of color that inspired our project [originally] was born from the observation of the neighboring Monumental Cemetery, an important historical site in Milan,” explained Roggero. “The Monumental Cemetery has its entire coating created with horizontal black and white stripes, so we started our design the same — by inserting horizontal rows of black and white with the addition of 14 colors. Then, we created textural and colorful vertical lines to add volume to the Tower, and to also create movement and spectacle to the project. In addition to the ceramic coating, we colored 22 curbs in relief and the top front of the Tower with black paint for the exterior, supplied by Mapei, to give a break and a strong emphasis to the whole structure.”

To bond and grout the new tiles, Mapei provided Ultralite S1 Quick, a single-component, high-performance, deformable, lightweight, rapid-setting and hydrating cementitious adhesive with no vertical slip, good trowelability, high wetting capacity and extremely high yield, developed for ceramic tiles, stone and thin porcelain tiles; along with Ultracolor Plus, a premium, rapid-setting, polymer-modified, color-consistent, non-shrinking, efflorescence-free sanded grout. The joints were subsequently sealed with Mapesil LM, a solvent-free, odorless, non-staining, neutral cross-linking silicone sealant for natural stone, marble and agglomerate stone.

After replacing and repairing the various tiles around the structure, the installation team repaired and painted the 24 115-foot-tall concrete ribs that needed reconstruction. To restore the concrete ribs, installers used Mapefer 1K, a single-component, anti-corrosion cementitious mortar for steel reinforcement rods; and Planitop Rasa & Ripara (“Smooth & Repair”), a thixotropic, fiber-reinforced, rapid-setting, shrinkage-compensated cementitious mortar for repairing and smoothing concrete. The pillars of the tower were then painted with Elastocolor Primer, a solvent-based, high-penetration consolidating primer developed to even out surfaces; and Elastocolor Waterproof, a waterproof, easy-to-clean acrylic paint for internal and external surfaces in permanent contact with water.

The final stage of the project, completed to better waterproof the structure, was the implementation of a double waterproofing sheathing. To repair the waterproof layer on the round roof, a European subsidiary of the Mapei Group, Polyglass, contributed an assortment of products, including Idroprimer, Polyflex Light, Polyflex Light Mineral and Mineralfix.

In order to successfully complete all of this work without comprising the architectural integrity of the Rainbow Tower, a Multicom modular scaffolding system was utilized throughout the duration of the project, which was supplied from Condor S.p.A. in Castel San Giorgio, Salerno, Campania, Italy. “The main feature of this system is the multi-directional crosspiece and upright anchoring coupling, which made it possible to adapt the scaffolding to the sometimes convex-shape of the Tower, in a way uniform and adherent to the circular wall, with a system of internal overhangs realized by means of specific accessories,” said Roggero. “Thanks to the performance of this system, the structure was built to the highest quality standards, and in a very short time.”

To ensure everything went according to plan, Roggero and the designers from Studio Network Original Designers 6R5 Network personally followed the progress of work alongside Claudio Bazzea, foreman and chief architect of Bazzea, and Mario Marchi, chief of security of Bazzea. “There were not any particular problems [in regard to the installation], given the high level of the workers and detailed plan of the project, which was prepared meticulously before starting work,” explained Roggero. “However, we had to adopt innovative techniques to get the best results with our operators and technicians from Bazzea when laying the tiles and painting the curbs and upper part of the Tower.”

Altogether, the complex restructuring of the Tower in 2015 took a total of 71 days. The Torre Arcobaleno forms part of the Wonderline project by Studio Original Designers 6R5 Network, which has been an ongoing effort for a number of years — linking initiatives in the world of art and architecture with the theme of color. According to Roggero, the colors of the Torre Arcobaleno express the desire to inhabit our planet intelligently, creating a harmony between technology, nature, innovation and tradition.

Since the Tower’s completion a little more than six months ago, the reaction has been overwhelming. “It was a big success, and everyone who attended the opening event was filled with emotion, thanking us for having supported this intervention,” said Roggero. “Perhaps one of the best compliments was receiving an email from the Director of the University of Texas detailing how ‘beautiful’ the Tower was.”  cstd

Torre Arcobaleno (Rainbow Tower)

Milan, Italy

Architect: Studio Original Designers 6R5 Network, Milan, Italy

Tile Manufacturer: Marazzi Group S.r.l., Sassuolo, Modena, Emilia-Romagna, Italy (10- x 10-cm ceramic tiles from the Sistem C collection)

Tile Installer: Bazzea (B Construction Technology), Vigevano, Pavia, Lombardy, Italy

Installation Products: Mapei S.p.A., Milan, Italy (Mapefer 1K, Planitop Rasa & Ripara, Elastocolor Primer, Elastocolor Waterproof, Ultralite S1 Quick, Ultracolor Plus grout, Mapesil LM sealant), Polyglass USA Inc. Mapei Group, Milan, Italy (Idroprimer, Polyflex Light, Polyflex Light Mineral and Mineralfix), Condor S.p.A., Castel San Giorgio, Salerno, Campania, Italy (Multicom modular scaffolding system), Fila Surface Care Solutions, San Martino di Lupari, Padova, Veneto, Italy (Fila PhZero, Fila No Paint Star, FilaStop Dirt)