Especificaciones Técnicas y Planos
2 OBJETIVOS .1 Objetivo General
2.2 Objetivo Específicos
Figure 15 Installed Light reflecting surfaces
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v.
Glazing
There is now a large amount of alternative glazing for windows, and it is necessary for the architect, in conjunction with his servicesconsultant, to write a detailed performance specification; this mustinclude the orientation of the window, its thermal and acousticcharacteristics, together with its capacity for solar shading. This is ofcourse in addition to the main function of the window which is theadmission of daylight and the introduction of the view to outside.
Further factors which may need to be taken into account, are whether itis thought desirable to have windows which open or are fixed, and its relationship to ventilation.
Glazing types which reduce the impression of daylight significantly,darken both the interior, and the view, whilst the view from the outsidetowards the building makes the facade look black. It is only whencomparisons are made between the view through a clear glass windowand one with a modifying glass that reduces the daylight, that the resultscreate disappointment . . . it is true to say that it is human nature toappreciate the natural environment, with all its variations of colour, lightand shade
There are basically three main types of glazing as follows. 1. Clear glazing
This can be single sheet, double or triple glazed or alternatively a ‘thick’ glass, but the more sheets or the greater the thickness of glass the more the daylight will be diminished, although the impression of the colour of
[AUTHOR NAME] 63 the exterior will still be perceived as natural.
Clear glass whilst allowing a high transmission of daylight, will at the same time and on certain building fac¸ades allow a high transmission of solar radiation. It is this fact that has led to the development of the more high-tech glasses designed to reduce solar gain, with their consequent loss of daylight transmission. Other means such as inter-plane blinds, located between the panes of glass, may present a solution. These would only need to be installed on fac¸ades subject to solar gain and then only activated when required.
2. Tinted glass
This is of two types:the first where the clear glass is itself modified in
such a way as to produce different radiant heat transmission characteristics, therefore the thicker the glass the lower the transmission ofdaylight, and the greater the control of radiant heat from sunlight.
The second type of glasses are those coated with microscopically thinlayers of metallic oxides which reflect the heat away and out of thebuilding. These coatings are applied to the inside layer of glass generallyin association with other panes in a sealed double glazed unit as aprotection, since on their own they would be vulnerable to damage.
3. Miscellaneous glazing
A number of different types of glazing are placed in this category, largely because they cannot be lumped together into a single category; they consist of the following:
Patterned glass, wired glass, laminated glasses and glass blocks. Patterned glass
Any number of patterns can be rolled into semi-molten glass, to provide decorative or diffusing sheets for various purposes, though rarely for windows, since their capacity for light transmission will be modified. Wired glass
A similar process is used for the manufacture of wired glass, where a wire mesh is sandwiched within the thickness of the glass. This used generally 26 Daylighting: Natural Light in Architecturein security situations, and sometimes as a protection to vulnerableskylights.
Laminated glasses
Similar methods of manufacture are used for laminating sheets of plastic between sheets of glass, again used for security reasons as resistance to
[AUTHOR NAME] 64 impact. These reduce the transmission of daylight.
In museums where exhibits are exposed to daylight, it will be necessaryto control the entry of UV light. This may be done by the use of
laminatedglasses, where UV absorbing filters can be laminated between the sheets
of clear glass. Glass blocks
These were a popular form of glass wall in the 1930s, having thermal characteristics due to the hollow nature of the blocks, which, because of their structural nature are still in use today for the introduction ofdaylight into new buildings, but special openings will be required toprovide a view. High tech glazing
There are a number of glazing types which fall into this category, the most advanced of which are the photovoltaics, where the glass itself is designed to generate electricity from solar radiation on south facing exposures, which can then be used within the building to reduce the energy required for the artificial lighting.
vi. ATRIA
Whilst the word atrium started as the central court of a Roman house, admitting light and air to the surrounding dwelling space, the word has taken on a wider meaning as described in the CIBSE LG10 daylight and window design.
‘An interior light space enclosed on two or more sides by the wallsof a building, and day-lit from a roof of transparent or translucentmaterial and, sometimes, from glazed ends or sides. It permits theentry of light to the other interior spaces, linked to it by glazed orunglazed openings.’ The atrium is therefore a further development of the dome or vault allowing daylight into the central areas of the great houses. The modern atrium will be covered by a glazed skylight, which, whilst slightlyreducing the amount of daylight, monitors the external atmospherekeeping out the rain, whilst contributing to ventilation, and reducing thenecessity for air-
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Case Study
i.
KimbellArt Museum.
The Kimbell Art Museum in Fort Worth, Texas, hosts a small but excellent art
collection as well as traveling art exhibitions, educational programs and an extensive research library. Its initial artwork came from the private collection of Kay and Velma Kimbell, who also provided funds for a new building to house it.
The building was designed by renowned architect Louis I. Kahn and is widely
recognized as one of the most significant works of architecture of recent times. It is especially noted for the wash of silvery natural light across its vaulted gallery ceilings.
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esign is enhanced by the use of natural materials like travertine and white oak, combined with glass, concrete, stainless steel and aluminum.
The narrow skylights that are along the vaults are on the inside of aluminum reflectors, while the galleries provide a diffuse natural light
Figure 19Conceptual sketch of interiors. Kimbell Museum.
To express the differences and the inherent qualities of materials, the arc of the roof-deck concrete is separated radially from the curve of the adjacent wall covered with travertine.Although the creation of a space within, through the light, is achieved by the particularity of the roof to beam the light. This peculiarity has become the most popular of Kahn, distributors of natural light through a small slot into the sky and along the concrete vault.
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