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The choice of light and natural materials for the interior also reinforces the building's public character of the institution and is intended to encourage visitors and citizens to participate in public life.

The overall form was defined in such a way that it relates to, and reunites, the scale differences of the immediate urban context. On one side, the building is higher to respond to the city scale of the Raoul Wallenberg Square, while on the remaining sides, the building is more modest in scale, where it faces the residential area.

The main entrance is located on the southeast corner, addressing the Stadhuisplein. This opens into a spacious reception area with a broad flight of stairs leading to the assembly chamber above, which projects over the entrance to express its accessibility to the public.

The exterior elevations are treated as a continuous but layered skin, wrapping around and connecting the three parts of the building, composed of the city hall, the services department, and administration facilities. The various layers slide over one another, revealing a surface that is appropriate for the function it covers.

The double-curved tempered-glass panels that characterize the outward appearance of the building are held in place top and bottom in stainless-steel U-profile sections. The photographically applied leaf-print pattern that covers the entire surface of the building fits together like a puzzle.

Inside and out, the decorative effect also provides solar control and a measure of privacy for the building's users. The pattern appears more dense on those elevations exposed to direct sunlight, casting cool shadows reminiscent of a leafy forest. The pattern thins out again where solar gain and glare are less of an issue.

By changing its appearance, much like a chameleon responds intuitively to its environment, the city hall responds to both its programmatic and spatial requirements, as well as sensitively reacting to the urban nuances of its context. Without succumbing to the historically monumental image of the city hall, the building is nonetheless an iconic gesture and a radical new presence in the city. It is at once an open, inviting, and accessible institution, reflecting the image of this growing community.

Layered Glass

Laminata House (2002) in Leerdam, The Netherlands — home of the Dutch glass industry — was programmed as a glass house for an artist and designed by Kruunenberg Van der Erve Architecten for the Leerdam Housing Association (GWL Koopwoningen).

In plan, the single-story, flat-roofed house is split into two parts longitudinally; the larger portion accommodates the main house with two double bedrooms, shared bathroom, and study. The smaller portion accommodates a bathroom and entrance hall. Between the two wings is an open-plan living and dining space with adjacent terrace and an open, double-height entry courtyard that descends to a basement housing a garage and studio space.

The Laminata House uses glass for its main facades, but not as typical flat-sheet or double-glazed units. Rather, the walls and indeed the entire structure are composed purely of glass. It is a bold experiment that uses glass sheets structurally, while at the same time responding to the privacy and security requirements of the inhabitants.

The house is composed of individual layers of 2/5-inch- (1-centimeter-) thick laminated glass, stacked vertically as 10,000 separate sheets that are cut individually and glued on site with a silicon-based sealant. The width of the resulting walls varies from 8 inches (20 centimeters) to 6-1/2 feet (2 meters).

The curving path taken by the "knife" with which the glass is carved is best seen in the main hallway that runs the entire north-south length of the house from the entrance to the main living areas. Here, the glass ebbs and flows in a finely honed sculptural mass, the exposed ends of the sheets of glass creating an unexpectedly rich pattern that ripples across the surface of the walls, enhanced by the play of light and shadow.

The variable light traversing the uneven thickness of the walls creates a striking effect, passing from the dense protective opacity of the thickest walls to end in the limpid transparency of the thinnest plates.

The lengthy four-and-a-half year research, development, and construction program was partly due to the difficulty in finding a suitable glue with which to bond the sheets of glass. However, a revolutionary solution was developed to ensure that the glue used is UV-resistant and permanently flexible while accommodating the expansion and fragility of the glass.

Thus there is a certain amount of structural movement preserved between each sheet of glass in order to provide flexibility in the whole. As for strength, although a single sheet can easily be shattered by a hammer, taken together the laminated glass is stronger than concrete.

The experimental solution was the outcome of a unique collaboration between the architects, the Netherlands Institute for Applied Science (TNO) based in Delft, which was responsible for the preliminary research exercise, the glass company Saint Gobain, which carried out the glass fabrication, and Den Braven Sealants, based at Oosterhout.

The building sits on a concrete slab and is served by underfloor heating and an electrical conduit system. The thick walls absorb heat gain and dissipate it without transferring it to the interior, eliminating heat fluctuations and the need for cooling in the summer. However, it was recognized that the same walls presented a particular challenge due to the inability to create penetrations for service cabling.

The result is an astonishing feat and, unlike other glass buildings, is unique in its treatment of light and its "ice-like" volumetric mass. Unlike previous experimental essays in the use of glass as an architectural material, in which it is employed primarily for its apparent weightlessness and transparency, architects Gerard Kruunenberg and Paul Van der Erve have contrived to renew the experiential properties of the material.

In the Laminata House, glass loses its fragility, becoming weighty and acquiring mass and volume. The result totally redefines the use of glass as a building material, and as a result represents an architectural revolution.

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Brent Richards is a practicing architect and director of the Design Laboratory at Central Saint Martins College of Art and Design. He is a leading expert in glass technology and principal of Design Antenna Architects, London.

This article is excerpted from New Glass Architecture, copyright © 2006, available from Yale University Press and at Amazon.com.

SUBSCRIPTION SAMPLE The main entrance of the City Hall in Alphen aan den Rijn opens into a spacious, daylit reception area with a broad flight of stairs leading to the assembly chamber. Photo: Dennis Gilbert Photographically applied leaf patterns in the double-curved glass panels. Photo: Dennis Gilbert Ground-floor plan and longitudinal section, City Hall in Alphen aan den Rijn, The Netherlands, by Erick van Egeraat Associated Architects. Image: Erick van Egeraat Associated Architects The Laminata House in Leerdam, The Netherlands, by Kruunenberg Van der Erve Architecten is made of 10,000 laminated sheets of glass. Photo: Dennis Gilbert Inside the Laminata House, varying degrees of transparency and light quality are created by the glass walls. Photo: Dennis Gilbert In the hallway, the sculptured glass ebbs and flows to create a pattern that ripples across the wall surfaces. Photo: Dennis Gilbert Ground-floor plan of the Laminata House. Image: Kruunenberg Van der Erve Architecten New Glass Architecture, from Yale University Press. Image: Yale University Press and Laurence King, photo by Dennis Gilbert   Click on thumbnail images to view full-size pictures.