the UnKnot Tower
A knot is created by beginning with a one-dimensional line segment, wrapping it around itself arbitrarily, and then fusing its two free ends together to form a closed loop. When mathematical topologists consider knots and other entanglements such as links and braids, they describe how the knot is positioned in the space around it, called the ambient space. If the knot can be moved smoothly, without cutting or passing a segment through another, until it coincides with another knot, the two knots are considered equivalent.
The new 35,000 m2 hybrid building introduces luxury living and services for both the hotel and the condominium programs. The tower is sited prominently at Plesmanlaan, at the edge of the historic center of Leiden. The unique form of the Unknot Tower is generated by intertwining the tower’s form and programs as a knot. A crystalline center void is introduced, around which all public spaces are organized. These hotel amenities such as lobby, champagne bar, conference center, spa, restaurant and pool are thus fluidly connected and allow both hotel guests and residents access. The hotel, retail, and residential condos are thus sharing programmatic overlaps, generous services, lifestyle amenities and open outdoor spaces.
The Tower’s knot form negotiates the varying site conditions by means of a series of faceted surfaces, which simultaneously differentiate views, light and privacy levels. Archi-Tectonics developed an algorithm for the pixilation of stone and glass, creating varying quantities of translucencies, as the tower moves obliquely away and towards the adjacent sites. Simultaneously the stone and glass curtain wall provides a highly insulated façade, improving the energy efficiency of a typical glass curtain wall, while providing passive solar energy. The effect of the slating surfaces is also enhanced by sensor controlled lighting and solar blinds.
Two distinct outdoor urban spaces are provided for, one at each end of the “knot” loop: a ground level hotel entry plaza at the north side, and the cantilevering pool at the south façade. Inside the knot one finds a third private urban space; the crystalline void located on the fourth floor, which contains a terrace and roof garden, looking out over the pool shimmering below.
The building contains a Four Star Hotel of approx. 194 keys, a Holiday Inn Express of approx. 129 keys, 3 restaurants, a Conference Center and 1,000m2 Event Space, a Spa, and a library. The top floors of the building are occupied by approx. 27 Luxury condominium apartments. More than 9,000 m2 of parking serve the new building as well as the surrounding development.