Unknot Tower Philadelphia, USA

The new Unknot Tower (also known as the GHM Hotel and Condominium) is set to be the latest architectural breakthrough for Philadelphia. The tower has been designed by CREI (Creating Real Estate Innovations) in conjunction with the groundbreaking Dutch architect Winka Dubbeldam of Archi-Tectonics (Professor of Architecture at the Penn School of Design).

The site for the tower will be at 1,122-1,128 Chestnut Street (site is at the corner of 12th and Chestnut, and Samson Street will be at the rear of the building) in the heart of the Philadelphia commercial district.

The 27-storey 279ft tower, being developed by GHM Hotels, will be used as a 145-room boutique hotel although there will also be a number of apartments (with hotel service) and retail shops in the development including a L'Atelier de Joël Robuchon restaurant and a spa.

The hotel, which will occupy most of the tower, is expected to be a Setai Hotel (sister hotel to the Setai Hotel in South Beach, Miami, the only other GHM Hotel in the US). The groundbreaking for the tower is due to take place in mid-2008 and the project is scheduled for completion in 2010.

UNKNOT TOWER DESIGN

With a style born of the Faculty of Architecture in Rotterdam and Columbia University in New York, as well as associations with architects of the calibre of Stephen Holl, Bernard Tschumi and Peter Eisenmann, Winka Dubbeldam has created a design for a tower that is based on knot theory (as a mathematical concept knots are defined as embeddings of a circle in three-dimensional Euclidean space). In this case the tower design is a knot that can be unravelled into a continuous circle and known as an 'Unknot'.

The tower is similar in some visual respects to the Rem Koolhaas design for the China Central Television Headquarters in Beijing but on a much smaller scale. The 'glass' tower has a triangular profile with the apex leaning back from the frontage in Chestnut Street (making the shortest part of the structure at the front).

The tower will use glass and stone in the façade (glass will have a specially designed pixelated pattern incorporated) in such a way as to reflect natural light to all areas in a specific way and produce almost a crystal palace light effect. The tower structure will have an unwound but continuous shape, which leaves a space in the middle that will be occupied by several relaxation terraces where residents and guests can observe the surrounding activities and also the shimmering light effects generated by the façade (this area above the entrance will also provide easy access to all areas of the building).

The tower will also have two major exterior features, firstly the entrance plaza at Chestnut Street that will have a musical garden (also excellent disabled access) and secondly there will be an elevated terrace with a pool and relaxation area for hotel guests and residents. The tower will also have a two-level underground car park for use by residents and guests (accessed by a curb cut-out via Samson Street).

THE RESTAURANT

Joël Robuchon will be setting up his third L'Atelier de Joël Robuchon five-star restaurant in the tower (the others being in New York City and Las Vegas). The restaurant is based around a concept of creating a greater connection between the kitchen and the dining room by knocking down the conventional boundaries.

The seating in the restaurant will be arranged around a 36-seat V-shaped bar that will look directly into the kitchen providing a direct behind the scenes arena view. The restaurant will serve classic dishes in smaller tapas-style portions so that the guest can eat as much or as little as possible according to their needs.

UNKNOT TOWER CONTRACTORS

The architect responsible for the design of the tower is Archi-Tectonics (Principal Winka Dubbeldam). The architect of record for the project is J Roller Architect and the project designer is Bittor Sanchez-Monasterio.

The consultant structural engineer for the project is Thornton Tomasetti Engineers and the mechanical engineers are Edwards & Zuck Engineers. Finally the curtain wall consultant is Israel Berger.