Green Building in Glass: National Technical Library

Joining the ever-growing list of green glass wonders in architecture is The National Technical Library, a “hi-tech living room” for students, officially opened on 9^th Sep 2009 in the campus of the University of Prague, Czech Republic. This massive project was completed by Czech architects Projektil Architekti. This building received the prize for best modern building in a historic locale from the Club for Ancient Prague, for being not just state-of-the-art, but also green and energy-efficient. The building cost over US $140 million to construct.

This structure has made its mark in outstanding green buildings of the world.  Its façade is divided into glass and blind parts on the surface in a nearly balanced ratio in order to optimize natural energy flowing in. A double-walled structural glazing makes the façade glisten at night. The building is shaped like an old-fashioned TV screen; essentially square in shape but rounded at the corners.

This green building has three floors below the ground and six floors above the ground. Floors 2-6 are arranged around a central atrium which admits sunlight. The atrium is also equipped with a skylight and is the main space of the building. All lighting points are at the centre of the building – an arrangement which aids orientation and ensures that the floors of the glassy interiors look bright and colourful all the time.

An asphalt-based floor covering material – ‘bitu-terrazzo’ – that cuts out sound has been used on the ground floor. The underground floors house the book storage, technology centres, supply stores and parking.

The roof is covered with extensive green glass panels to create the fifth façade of this green building. This can be viewed from surrounding taller buildings. This roof also helps slow down draining during heavy rains.

Large open rooms are situated along the south-east, south-west and north-west sides of the building and the office rooms are on the north-east side of the building. This arrangement helps to reduce the solar heat load but it also provides the required daylight into the building. The plot mirrors not only allow the natural light to the different areas but also responsible for the distribution of warm gain.

The building has an easy system for pre-cooling during summer nights through ventilation achieved by simply opening the glass windows. The library needed a fire safety system that would not damage library stocks. So an automatic water mist-spraying fire extinguishing system – which is more asset-friendly than water, does not require large-capacity storage vessels and also facilitates installation of the pipe work system within the building – was installed.

This iconic library hosts 1.2 million volumes of books alongside an exhibition hall, a conference centre, café and bookshop. There are 1,200 seats in the study area and 300 seats in the relaxation area. The conference hall seats 200 while the café, 150. The building is wi-fi enabled and can shelter 300 cars and 200 bicycles at a time. National Technical Library is expected to attract 900,000 visitors every year.

Glass Windows with Low-e Glass

A window is a quadrangular opening in a wall that allows light, air and sound to pass through, provided the window is not closed or sealed. Windows are usually glazed (made of glass) or constructed using an appropriate transparent or translucent material.

Low-E Coated Glass in Window Technology

Low-E coating stands for Low-emittance coating on a solid surface. It is an extremely thin, nearly invisible film of metal or metal oxide layers deposited on a window or skylight. Its primary function is to reduce U-factor by restricting radiative heat flow. The key methodology by which heat is transferred in multilayer glazing is thermal radiation from a warm sheet of glass to a cooler sheet. Covering a glass surface with a low-emittance element and placing that coating into the gap between the layers of glass impedes this radiant heat transfer significantly, thus reducing the overall flow of heat through the window.

Benefits of Low-E Glass

Low-E technology is over two decades old in the glass market. Although its benefits have been duly acknowledged, glass with low-e coating is rarely used in construction. There are several priceless advantages and cost savings that can be achieved by using low-e glass.

During the severe energy crisis the world faced during the 1970s, everyone endeavoured to minimize consumption of natural resources. In case of glass, energy was lost by way of heat loss through the glazed surface. In 1980, the commercial development of thin, transparent, low emissive coatings literally revolutionized the concept of energy savings in windows. The low-e coating, placed on the inside of the insulating glass unit, enabled the sun’s short-wave energy to enter the room and at the same time prevented internal warm air from leaving the room.

SOURCE: www.glazette.com

R128 – Green in Glass

That all architectural structures are covered by solid opaque walls on all four sides to maintain privacy and security is a given. So, a home with walls of glass that offer a clear view of the inside is bound to create more than just a ripple, and 128 Werner Sobek does just that. This rather novel concept in residential architecture seems to have broken through all conventions and set a new – if not higher – standard in innovative construction.

R128 Werner Sobek is four-storey house, floating high on a hill overlooking the city of Stuttgart, Germany. Inside this curious creation, there are no doors, switches, interior walls or partitions and no closed rooms. But what takes the cake is that the home generates its own energy. The construction material used to create R128 is one hundred percent eco-friendly and recyclable.

R128 has a most attractive glass façade and is devoid of a basement. High quality triple-glazed glass with inert gas filling is in use. The use of a modular design, complete with glass panels and steel frames ensured easy assembly and disassembly of the construction. The insulated glass panels prevent overheating of the interior during summer and loss of energy and warmth during winter. The supporting steel frame comprises of 10 tons of steel.

The ceiling of the Werner Sobek glass house consists of prefabricated panels overlaid by plastic. Beneath the unscrewed floor, aluminium ceiling panels are affixed by clip connections. Lighting, heating and cooling systems are fitted into that layer and this acts as an acoustic absorber pattern.   

Sensor controlled doors have been installed on the upper and lower levels of the house. All appliances and environmental systems are also controlled by motion sensors and voice commands. The front door has a voice recognition feature which allows it to open automatically on a voice command. Water faucets in the bathrooms are regulated by sensors. Windows are controlled by touch screen technology.

Every floor has two folding windows each, which allow natural daylight and fresh air to enter the house. During summer, cool water running through the floor elements removes excess heat from the entire house with the help of a heat exchanger. Thus surplus energy is stored for use in winter. This ensures minimal energy consumption. 48 solar powered modules with a total capacity of 6.2 KW are installed on the rooftop, which are responsible for supplying all the power required by the pump system.

This green show-house is expected to go a long way in promoting energy-efficient architecture.

Walking on Glass – The Grand Canyon Skywalk

An adventurous life is, at some point or the other, dreamt of by most people. A dormant desire for thrill and excitement lies within all of us. Ever imagined standing on a platform of glass 4,000 feet above a river? If you have, then try the Grand Canyon Skywalk. Constructed over the Colorado River at the edge of the Grand Canyon in Arizona State, USA, this skywalk is a dream comes true for adventure lovers. Walking on this massive glass platform gives one the feeling of floating on air.

This stunning structure was built by none other than French multinational Saint-Gobain and was funded by the Hualapai Indian tribe in partnership with Chinese-American businessman David Jin. The construction of the skywalk began in mid 2006, and it was ready for public use on 28^th march 2007. The cost of construction exceeded $30 million.

This engineering marvel is horse-shoe shaped and extends to 70 feet from the cliff edge of the Grand Canyon at the western rim. The skywalk stands at a height of twice that of the world’s tallest skyscraper. It can accommodate 120 people and a weight of 72 million pounds at a time. It can also withstand winds speeding at 100 miles per hour and coming in from 8 different directions; and even an earthquake measuring up to 8.0 on the Richter scale.

The floors and the sidewalls of the skywalk are made up of four inch thick glass. The floors are of specially-made German glass which bequeaths durability and beauty to the structure. 1 million lbs of steel have gone into the making of this construct, each 2” thick, in a design that allows control on heat, cold and wind. The steel is in the form of frames that are affixed to the Grand Canyon with the help of caseins and micro piles measuring 46 feet down into the solid bedrock.

Each of the 46 panes forming the skyway were constructed using five layers of glass bonded together and laminated, weighing about 1,200 lbs apiece. This makes the glass extremely strong and provides a crystal-clear view of the canyon below. The structure also includes dampeners that help minimize vibration.

Skywalk is an 80-yard leisure walk around a semi-circular glass path which juts out of the canyon rim. The facility includes a 6,000-sqft visitors’ center on three levels, a museum, a movie theatre, a VIP lounge and several restaurants including The Skywalk Café, which offers an outdoor setting on the edge of Canyon.

Visitors have to pay $25 to use the gangway, in addition to the entrance fee for the National Park. Visitors have to wear special shoe covers for protection from slips and scratches. This bridge offers a chance to explore the wonder that is the Grand Canyon.

Flickering Exterior of Burj Dubai

Burj Dubai – Spoken of as the tallest man-made skyscraper ever built, is under construction at Downtown and is likely to be unveiled to the world by the end of this year. At present, this structure stands at a height of 800m. This, however, is not its final dimension – which will be revealed only upon completion of construction.

The exterior cladding of Burj Dubai, developed by Emaar properties PJSC, was completed recently. The façade of this building is made up of aluminium and glass. The total weight of the aluminum used is equivalent to that of five A380 aircrafts. In May 2007, Arabian Aluminium Company in association with Hong Kong based Far East Aluminium began work on the exterior with more than 380 skilled engineers and on-site technicians.

On the whole, 24,348 cladding panels have been used over a total curtain wall of 132, 190 sq m. The last cladding panel numbered 24,348 with a weight of 750 kg. This was installed at the height of over 662m. The total 103,000 sq m of glass used in the cladding panels can cover 14 standard football pitches, while the15,500 sq m of embossed stainless steel used can cover 34 National Basketball Association specified basketball courts. The cladding material was specially made using advanced engineering techniques. Cladding includes high-performance reflective glazing, aluminium mullions and textured steel spandrels with vertical stainless steel tubular fins.

Doubly glazed and factory sealed panels of more than 18 different strength specifications and over 200 sizes have been used. The panels are of varying thicknesses and each feature two glass pieces of about 8mm to 12mm thickness, buttressed by a 12 mm spacer for strength and resilience. The length and thickness of each panel depends on the height and the location where the panel is to be fixed. Also, the strength of a panel needs to increase with an increase in altitude. Hence, panels at higher altitude are strengthened with stainless steel in addition to aluminium.

At the initial stages, 20-30 panels were installed per day. This number was eventually increased to 175 panels per day. As the altitude increased, the workforce faced grave risk; to minimize which, curtain-walling for the spire was pre-installed on the ground and then lifted to the summit as secured.

A “flickering cladding” was designed to maximize resistance to heat from the sun. This is expected to minimize load on air conditioning systems, thus improving the energy efficiency of the tower.

18 window-washing units have been built to ensure cleanliness of this huge façade. These are built using 9 track-mounted telescopic cradles, each with an extendable arm which can reach out to a distance beyond 20 meters.

The observatory deck on the 124^th floor has been named “At the Top”, and will present to visitors with information on the “History and Evolution of Dubai and the Burj Dubai” and also a view of the whole city. This structure is expected to be a benchmark for high-rise developers in creating environment-friendly, sustainable and futuristic buildings.