Saturday, June 28, 2014

MICRO VENTILATION


Micro Ventilation > Post by Gautam Shah

Thatched roofs are natural ventilating systems Japan Dwelling Wikipedia Image by っ
Micro ventilation is a very important passive means of adjusting heat and moisture for Hot-arid and Hot-humid climates. It is one of the easiest and consistent ways of managing comfort in enclosed and semi-open spaces. It relies mainly on external or macro conditions of the terrain or region, and it is efficiently managed by appropriate interior design. Micro ventilation systems of vernacular design are time-tested solutions that have come down from one generation to another.
 Micro ventilation ensures that AIR enters or leaves an enclosed space through cracks, crevices, gaps or apertures in buildings’ structure and its components. Entry and exit of air chiefly occur due to differential pressures along a point to point paths of movement. The differential pressures mark the windward and wind-off sides. The working pressure is regulated by both the size and shape of the layout scheme of the buildings and individual components of the building. The temperature of surfaces and surroundings near the wind-ward and wind-off sides directly affects the air pressure.
Tropical houses of Bamboos have passive ventilation system Wikipedia Image by  Bellenion

In a building micro openings are both circumstantial and designed. The micro openings also serve different functions depending on their, size, shape, nature of passage, adjunct internal and external elements and their closeness to the location of need (for ventilation). The functions besides the ventilation, include view out and in, provision of privacy and illumination without a glare.

ROOF RELATED GAPS are such as in the thatched and country tile roofs, loosely laid roof slates or stone sheets or intentionally placed micro passive vents such as lattices, chutes, hoppers, etc.
Konkan -W coast India Roofs as as micro ventilation system Wikipedia Image by PP Yoonus
GAPS IN UPPER SECTION OF WALLS are such as the unpacked ends of corrugated roofing sheets or terracotta tiles, ends of purlins and trusses when not tightly packed, and eyelets or oculi like holes in gables.

OTHER GAPS exist in and around openings such as doors and windows, as loose joinery, leaky fitments, ajar shutters, door bottom space, peep-holes, openings without shutters (gaps), latticed constructions such as of woven mats or fabrics, louvered openings, crack or fissures in building elements, expansion joints, unsealed joints, etc.

Merzuoga, Morocco Pic courtesy by Swee Chuan

Micro ventilation requirements inside a building vary depending on the use of the space, tasks, work-schedules, crowding in the space and presence of heat evolving means (hearths, machines, etc.) The ventilation requirements also depend on the amenities used for conducting the tasks.

The circulation or movement of air is affected, by the space profile (section), the work intensive volume and its datum, levels of ventilation (import-export) nodes, the encumberment by elements such as size and shape of external overhangs, the sill depth and its profile shape.
Attributes of good Interior air

Some experts have claimed that air quality of a room is chiefly determined by its CO2 concentration. This, however, is only partially true. The Indoor air quality (feel-good aspect), in a tropical climate (hot-arid or hot-humid) zone is more governed by the temperature, rates of movement (pressure) and the moisture content. These three factors are mutually dependent.

The air movement is factored by the temperature difference between entry-exit points of ventilation. Outside air has lesser moisture (except during raining conditions) then indoor air, so any level of ventilation, dilutes the interior humidity level and adds to the comfort. Movement of air also encourages evaporation and increases cooling inside a space. In dry arid climates smaller and deep-set openings create a strongly directional air movement allowing dwellers to locate their activities suitably. Deep-set openings also increase absorption of heat in the mass of the built-form or add simple cooling devices such as water wetted grass mats or fountains.

Why CO2 concentration is not critical factor for Indoor Quality of Air in Tropical Climatic zones.

1. The CO2 concentration in a tropical climate building is not a critical factor, because location of cooking area is invariably a segregated entity or an outdoor activity. There are no interior fire places as the climate does not require it.
Open air cooking -no CO2 concentration
2. In ethnic dwellings like that of Rajasthan (India), cooking facilities are in verandah, or as in Kutchh (Gujarat-India) Bhunga houses it is away from the house. In South Indian traditional homes cooking is a separate entity on the back side, adjunct to a verandah. In Utter-Pradesh (India) traditional houses had cooking areas as an out-house like facility. This pattern repeats across Africa, and other parts of Asia.

3. CO2 concentration is a problem where traditional fuels like woods, agriculture waste, animals dung and kerosene is used in enclosed rooms with integrated kitchen facilities. These conditions occur in comparatively in 1-colder climates, 2-in dense urban colonies and 3-where such fuels are used. The last two conditions can be relevant in tropical climate zones, but here too LNG, LPG, Bio-gas and electricity are replacing the traditional fuels. The traditional fuels are difficult to procure, require lager storage space and have low caloric efficiency.

4. CO2 concentration is not a problem in traditional or ethnic buildings, because the design and details have evolved over a very long period. Whatever facilitations not offered by the built-form are achieved by setting a life style. The Life style setting includes locating activities in most advantageous location and at time schedules. Continually shift the activities according to seasonal variations.

In many old buildings the micro ventilation system is almost sufficient for dilution of fouled air. The life style settings take the advantage further by exploiting air flow movement paths, pressure gradients and qualitative variations at different locations and time schedules. 
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Sunday, June 22, 2014

CLAY or MUD STRUCTURES - part - 3



FOUR: WALLS WITH FIRED CLAY SOLID BLOCKS



Chandigadh India Housing Bricks façade

Mud wall systems have one major drawback, their susceptibility to water. Other issues are their low load bearing capacity and heavy dead weight due to the substantial thickness. Mud wall systems are labour intensive and require frequent upkeep.


Mud blocks when fired in kiln at various temperatures and duration turn into ceramic product -the bricks


Bricks are the prime building blocks for constructing walls, roofs, lintels, floors and pavements. Bricks or similar blocks used in nearly every geographic region of the world. The materials used for making such blocks include clay, china clays , pozzolanic ash, cement and lime. Some of these materials are mined from nature or reprocessed. Brick are solids or hollowed masses. Bricks are cast in form-work or extruded. Bricks have many different sizes and shapes. Basically bricks have two faces, in wall construction the larger surface is placed parallel to the gravity. Exception to these rule include bricks used for arches, lintels or floors -where the depth of the block remains a critical consideration.
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Ziggurat Brick work

Brick are used with or without the joint materials. Joint-less construction or composition exploits the flat placement -or stability offered by the pull of gravity. Intermediate fillers and joining materials are used for bonding and also for levelling the surface.
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Joint materials used for bonding are generically called cements. These materials provide bonding by surface attraction, phase change (liquid to solid) and chemical change. Some of these materials achieve bonding after a period of setting and hardening, or achieve an instant bond. Bricks in thin form -as tiles, are often mechanically joined by screwing, clamping, etc. Such joints are used mainly for cladding or surface applications.
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Bricks are cast mainly from soils with high content of alumina and free silica. Though calcareous, chalky and high silica (fire clay) soils are also used for many special types of bricks (kiln lining fire-bricks).

Sanskar Kendra Ahmedabad by Le Corbusier

Bricks get their primary toughness due to removal of chemically bound water from the constituents of soil, oxidation of salts, and vitrification of silica matters. At temperatures above 300° C, some of the constituents start flowing producing a glassy mass. These and some of the oxides bind together all other materials, forming a hard mass. Later, on soaking the hydration of silicates and aluminates provide the extra strength. Over the years gradual carbonation of hydrated lime provides additional hardness. 


Colour of the brick, an important criteria for surface finishing is influenced by contents of the soils, range and duration of burning temperature, ventilation system of kiln, casting techniques etc.


Bricks are made from high alumina clays with small amount of colloidal or free silica. Many other additives are also used primarily to adjust the plasticity of the mass. Some of these additives are organic (grass, hay, rice husk in nature, which on burning impart porosity. Rice husk in addition provides siliceous substances which in combination with lime impart pozolana like cementitious bond. Powder of burnt broken bricks is added to clays in place of free silica sand to reduce shrinkage cracks during drying and burning.
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Bricks are variously permeable. Predominantly alumina bricks are more permeable than silica bricks. Under burnt and low temperature fired bricks are more absorbent compared to over burnt and high temperature (refractory) bricks. Hand pressed bricks (table mould) are less compact than machine made bricks, and as a result absorb more water. Hollow and perforated bricks are extrusion machine cast from a very wet and plastic mass. Roofing tiles and facing brick tiles are die mould cast with minimal mixing water and very high impact-pressure.


Indian Institute of Management Ahmedabad by L Kahn

Bricks of exposed masonry surface, if permeable allow bacterial growth such as mould, fungi etc. on the surface. Soluble salts present in the clay, usually get decomposed during the burning but immediately after highest temperature of firing and while cooling, sulphate of sodium, calcium, potassium and magnesium are formed with the help of sulphur from the fumes of the fuels. These salts on contact with absorbed moisture leach out on the surface. Most of the sulphate get washed away from the masonry surface, but magnesium sulphate does not leach out readily. It expands and causes cracks in bricks. Calcium sulphate though difficultly leached out, settles on the surface to form whitish scum
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Porous and rough brick surfaces are better for mortar adhesion than impervious smooth surface of a very vitrified brick, Over burnt or highly vitrified bricks have very low suction capacity for mortar binding. Over burnt bricks are dimensionally deformed due to running of the mass and unsuitable for masonry work.
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Next to the colour, texture and quality of the brick the masonry surface is characterized by the colour, material and technique of its joints. Jointing and pointing material for brick surfacing have to surpass the overall performance of bricks. High adhesion, low permeability and suitable colour matching are some of the attributes of a good jointing-pointing material. Flushed, projected and grooved pointing are used for brick work, of which flushed with string mark type of pointing is best. Unlike the projected or grooved pointing, flushed pointing does not retain dirt or water in its holds. The string marks are adequate guide path for any hair crack that may develop.
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Wednesday, June 18, 2014

CLAY or MUD STRUCTURES Part - 2



THREE: JOINTS OF MUD, DAUBING AND PLASTERS

Wattle and Daub construction

In locations where building stones or wood and grass products (bamboo, Cain, long straws) are available, Mud has been used as joint filler, daubing, layering or plastering material. In Himalayan range stone boulders have been used for creating walls. These were internally and superficially packed with mud or plastered. (Though the boulder walls, in spite of packing and joint filling remain unstable in earthquakes -are now banned.) In stone masonry the joint filling or external packing (lining) with mud, stops cold winds, rain-water penetration and insects proliferation.


Mud packed stone wall

Clay daubing is mud plaster over woven mats of bamboo, grasses etc. fixed over frames. Similarly wood, metal and other lattices are used to hold a layer of mud. This method creates, comparatively a thinner, and so a lighter wall structure. The framing structure provides the load-bearing capacity and lateral stability. Often inner partitions of Mud wall houses are made by this method. 



WATTLE and DAUB is a technique of creating both, in-situ walls and pre-cast panels that are attached to the framing of the building. It has been used since neolithic period. A woven lattice of wooden strips called wattle is daubed on both sides, with plastic slurry of mud. As the mass is very thin, it dries out fast with very little cracking. The surface is re-daubed on both sides to refill the residual cracks and achieve a smooth finish




Daubing left out to form opening

The mud requirements are small, so select quality mud is used. It is often rotted with dung, vegetation waste to increase the fibre content. Other binders mixed with the mud include lime, jaggery, gums, polymers, etc. For the second coat, materials like chalk, talc, iron oxides are used to add whiteness or colour.

Wattle is traditionally made by weaving thin branches or thin slats between upright stakes. The wattle made as loose panel forms in-fill plates. Nowadays to avoid white ants attacks, stainless steel, aluminium and polyester extruded longs and lattices are used in place of wood-based wattles. 


Clay daubing thin wall
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Friday, June 13, 2014

CLAY or MUD STRUCTURES Part - 1

CLAY or MUD STRUCTURES Part - 1

Post -by Gautam Shah 


Rammed Earth wall Taipa section of the Great Wall of China, Jiayuguan, Gansu, China
  Clay or Mud structures have been in use for the past 70000 or more years. Clays have been mined or collected from surfaces for the specific purposes such as for pottery, agriculture, construction of dwellings and public utilities. For each of these purposes suitable clays were identified, quality equalized and upgraded by selection, elimination, sieving and addition of other materials.


The first few structural properties of clay that were learnt included its behaviour in presence and absence of water, its angle of repose (steepest angle to which a soil material can be piled without slumping), and the qualitative differences among clays and the suitability for intended purposes.


For agriculture, fertility of clay, role of aeration and moisture content were known. For pottery and buildings, how the plasticity was governed by quality of clay, amount of water, and the additives. Plasticity affected the forming processes like shaping, moulding and bonding. Plasticity and rate of drying also affected the cracking in the mass on drying. For public utilities factors like angle or repose


In certain geographic terrains, such as stony areas, good quality soils are scarce, and use of mud in building construction is sparse. Yet Clay or Mud as material for plastering, daubing and joint fill-in is common everywhere in the world.





Clay or Mud structures can be classified into FOUR distinct types:

       1 Cutting, Dressing and Shaping the Soil

       2  Buildings Clay Walls (Sod, Cob, Rammed earth, Adobe)

      3 Joints of Mud, Daubing and Plasters

      4 Walls with Fired Clay Solid Blocks and Structural Potteries.



ONE: CUTTING, DRESSING AND SHAPING THE SOIL


Structures were created by taking advantage of terrain profile and features of the surroundings such as water body, prevalent wind direction, accessibility, stability of land mass, vegetation, distance of material carriage, etc. The interventions were in the form of cutting, dressing or shaping and filling-in. Stones as natural mass or its built form were integrated with such structures. The entities included community fire hearths and kilns, barrier walls, canals, causeways, bunds, burial sites, ritual and sacrificial places, defensive, and offensive entities. The structures were for personal as well as community needs.

Structures that reflect the environmental, political, economic and social changes taking place in the Neolithic age, were the megaliths, Stonehenge, Stone circles, burial barrows and chamber tombs, Dolmens, Causeway Camps, Ditch Rings, water wells and irrigation systems, stilted dwellings, temples and buildings for unknown (possibly religious or astronomical) purpose. Many of these must have been multi community endeavours requiring huge expense of man power effort and time.

Causewayed enclosures or Camps (UK and Europe) were some of the earliest clay utilities created by community effort for defensive, offensive and many other purposes. These were located on a high ground or a hill, encircled by one to four concentric ditches with an internal bank, and often close to a river or sea front. Unlike the causewayed enclosures the Ring ditches were smaller in size and served only funerary function. These enclosures were rarely permanently occupied, but rather visited occasionally by Neolithic groups. The sequential addition of second, third and fourth circuits of banks and ditches may have been to meet the ever growing populations. These were community interaction places, trading posts, animal compounds and defence retreat against intruders or invasion from other groups. Environmental archaeology suggests that the surroundings of the Causewayed enclosures were heavily forested (then), and required frequent clearings and ditch excavation for maintenance. Causewayed enclosures have very little built structures of non perishable materials like stones or adobe bricks.


Dolmens are Neolithic period structures of a single chamber or shaded area. Many different uses are ascribed for it, and the most plausible one is being a funerary place, portal tomb, grave or quoit. It is formed of one very large capstone which was hollowed out at bottom to insert three or more upright stones to support it. Dolmens were often covered with earth or smaller stones packed with mud to form a barrow. Dead bodies were placed here till their degeneration into bones. 


TWO: BUILDINGS CLAY WALLS

Great Mosque of Djenne, Mali

Buildings with clay walls were created for dwellings, storage, domestic animal yards, boundary walls, protective and defence structures. Clay walls are erected by three distinctive methods, namely. Cob, Rammed earth and Adobe. In all such constructions the chief raw material is mud, with addition of sand and straw. Sand increases the workability (mixing and handling) of clay and helps reduce the shrinkage on drying. Straw provides the reinforcement.

Mud walls are fairly water resistant, against occasional splashes, however continuous wetting such as persistent pouring can wash out the mud particles. The best strategy is to design entire wall structure holistically. Wall should be away from flowing rain water or other drainage system. The base of the wall must be raised over stone plinth or up to some height an extra thickness. Roof overhangs must be sufficiently deep to shade the walls from rain sprays as well as dripping rain water.


Cob and Rammed earth walls are monolithic structures, the consistency and homogeneity of the mass is very important to prevent cracking. The drying of the monolithic mass creates shrinkage cracks or gaps, chiefly at the free ends (near material change-overs) and sometimes at corners and junctions. The joints near doors and windows frames need to be re-packed


 Cob wall construction

SOD is a natural block of clay excavated or separated from a soil layer. Such soil layers are found at the dried out bottoms of tanks, rivers and other water reservoirs. The alluvial soil is often mixed with animal excreta and organic deposits. The deposition occurs over a sand layer, so is easy to separate and dig it out. These natural blocks are cut to desired width and used for erecting a sod wall. Sod wall construction does not require mixing of additional materials such as sand, straw and water. There is no shrinking on drying due to the presence of rotted organic materials. Sods are also used as roof building blocks. Sod blocks contain weeds and grass seeds or roots, which in moist season re-flourish.


Sod blocks for walls and roof

COB, cobb or clom is a technique of erecting a mud wall by stacking and packing the wetted mud, sand and straw. Clay mix was laid in courses and trodden -a process called cobbing. The construction process was slow as it was necessary for each layer to stabilize before the next could be laid. On completion and through drying the surface of the wall was scrapped smooth. It was then coated with a mud or lime mixed mud plaster. 


The walls were nearly 450 to 600 mm wide. The edges were fairly fragile so openings frames were placed midway in the walls. For load distribution of roof beams and purlins a plank or log of wood was embedded on the top part of wall. The thick mass of soil were insulative, and efficient for cold and hot arid climates.
 
Rammed Earth building method


RAMMED-EARTH BUILDING method is also known as Taipa (Portuguese), Tapial (Spanish), and pisé (de terre) (French). It is due to the compaction process that the method is called rammed earth building.


Such buildings are found on every continent except Antarctica. Such buildings are found in many different types of climates, such as the temperate, wet regions, semiarid deserts, mountain areas and the tropics. Rammed earth or adobe buildings need availability of useful soil and an appropriate building design including provision of the roof overhangs. 


Soil mass is brought to the site or excavated from near by locations, wetted and mixed well with sand and straw. The soil is placed in form-work of 200 to 300 mm height and well rammed with wide based wood rammers. The walls may also have some type of reinforcement grid.

 Rammed earth wall building is a very ancient method of construction. It has found new relevance by people who are looking for natural, local and sustainable building method. The method is labour intensive, but can flourish with low level technology and self help. The walls are simple to construct, strong and durable but massive. Rammed earth has very high heat capacity, that is can store heat through the day and release it in post-evening period. The walls are susceptible to water damage by rain splashes, so need protection through roof overhangs and continuous maintenance through mud or other plastering.


Rammed earth walls are nearly monolithic structures, but because of joints, the shrinkage on drying is negligible and load distribution much better.

Rammed Earth Building Saint Albin de Vaulserre - Grange en pisé - Isère - France

ADOBE is a sun-dried mud brick. The word adobe, with little change in pronunciation or meaning is with us for more then 4,000 years. 


The bricks are used as masonry units, by re-wetting the flat and edge surfaces and stacking, or by having mud mortar joints. The exterior and interior surfaces are generally plastered with mud, cement+soil or lime+soil mixtures. The walls are often clad with wood boards. 

 During forming, casting or extruding the mud blocks the soil is mixed with additives that reduce plasticity for easy casting, control cracking on drying and reinforce the material. Bricks are made in an open frame, 250 x 350 mm. The size is based on convenience of handling in terms of weight and mass. The mixture is filled into a frame, levelled by stripper. After the initial setting frame is removed and reused. Mud bricks are allowed to dry in shade to reduce cracking. Mud bricks are also cast as very long blocks (1000 mm). For mud bricks the most common additives are straw, paddy husk, dungs, and other agricultural wastes. Other additives include as lime, human animal hair, cement, asphalt emulsions, polymers, stone chips and dust.


Adobe Bricks

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Thursday, June 5, 2014

ARCHITECTURE of WINDOWS

Post -by Gautam Shah 
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Windows have originated as very distinctive opening system from Doors. The door for many years served the functions of a window. The specific form and unique functions of the windows were formed over several centuries. The doors, unlike windows had to be ‘grounded’, and that was the most remarkable difference between the two.
In Egyptian temples the openings were tall gaps, shuttered at the bottom for little more then the human eyesight level. Rest of the upper opening was a window for the Sun God Ra to enter. The window required no shutter for that climate. For the colder climates, all windows like openings had to have option of shutting out. Solid wood planks or rugs curtains covered the window. It was either closed-dark or open to winds and cold
Windows were placed in the door and beside the door to deal with the unknown visitors. Such windows were subjugated by the identical and often the superior functionality of the door. A window had its own distinctive functional identity only when placed away from a door. It was Palladio, who successfully joined them together. The side-lites, as the window accompanying the door is called, came in as a simplified form after Palladio’s very elaborate composition. Fan lights or Transom windows placed over a door are as old as the arched openings. But in Early Gothic architecture the upper section of the door was an opaque tympanum and the window was a separate entity, like between two columns or as a rose or oculus (circular) opening.
France-Paris Notre Dame
The early wall punctured windows were spaced apart to maintain the integrity of the load-bearing wall, but the windows had to be architecturally linked together by other decorative elements on interior as well as exterior face. On interior front the chauffeuring of the intrados helped window gaps seem to be closer. But on exterior face the windows were grouped by extra bands at the sill and lintel level.
Windows are visually related to each other by placing them in a linear sequence, such as at the base of a dome in Hagia Sophia, Constantinople, or as a planner matrix, such as in Venetian palaces. Windows were placed in repetition of units, or a large window unit was divided by mullions, transoms and traceries. Corbusier has used the brise de soleil to create a surface texture.
An arched window does not allow stacking, unless substantial intervening floor heights are available to accommodate it. An arched window is as tall as its width, forcing one to restrict, the size of the opening, or increase the floor heights. Head levels of arched windows for different widths of openings are problematic. A pointed arch, with its capacity to negotiate different heights allows equalization of head levels for different widths of openings. 
Very tall window openings were suitable for public or religious buildings like church, but openings for domestic buildings were mostly flat headed. In tall buildings the mullions continued in the arched openings, often following the curves of the pointed arch. In domestic buildings, due to smaller scale of the openings, the arches were less common. Flat headed openings were small, and so heavy stone mullions were not required, and instead the divisions were formed by very lean wooden mullions.
Nepal window without glass

Windows of religious buildings were covered with pot and stained glass, and later with grisaille paintings. But domestic buildings for a very long time continued with solid planks of wood as glass was out of their reach. Later clear and colour free glass was used. In religious buildings there were very few open-able sections of the windows, which had very distinctive position, separate from the fixed glass panes. In domestic buildings the windows were part of a composed entity where the open-able shutter itself was glazed.

 
Very narrow or slit windows occur at wall terminations or structural junctions. It presents a darker vertical line during daytime a brighter line when backlit at night time. Lancet windows were used to accentuate the vertical nature of towers.
Rosslyn Chapel UK

Small size apertures are used as windows, when appropriate glazing materials (cost, availability and technology wise) are not available, such as for blizzard prone buildings or tropical housing. Small windows are used for limited view, privacy, ventilation and exchange. Acutely specific purpose and location-based windows are small as these serve a very limited purpose such as for sleeping on the floor, seat level view, privacy, banking or business transactions, safety against falling off and as a social punishment in jails.

Architecturally windows have been used as texture creating or surface modulation unit. Windows are set back from the masonry surface of the wall so create a play of shadows, and help emphasize the depth or the massiveness of the walls. An open gap allows one to view the interior space which is deeply shadowed or shows up the colour furnishings inside, adding a variation to the usually monotonous facade
 
The surface of the glazing is very smooth, glossy and reflective of the changing surroundings, makes a very vivid element over the dull, static and opaque face of the building. These aspects are key issues in urban architecture of curtain walls. A window allows one to see the inhabitants of the building making it very ‘lively’. Window treatments on outside or inside personalities a house, such as seen in row houses or public housing. A small window or covered window raises curiosity about the activity or the occupants inside.
A window occurs as a single, few or multiple units over a facade. As a single unit it creates a focus, which may be dwarfed by the scale of the monotonous masonry surface. To emphasize the window many architectural elements are appended to the window face, such as pediments, Chhajjas, side columns, pilasters, cornices, etc. Few windows over the facade form linear patterns by their one to one relationship. Balanced patterns mark a stable architectural entity like with historical monuments. Few windows, each different from the other and with unique settings reveals the multi functionality of the architectural entity or poor planning. Such windows often have few common elements and some distinguishing features based on orientation, location, floor level, interior space usage and neighbouring elements. Multiple windows are marks of public spaces. Multiple windows due to their consistency provide a sobriety in chaotic urban setting. Multiple windows of different sizes and forms are grouped under a larger entity like an arch, overhang or brise de soleil (Corbusier in Chandigarh). Multiple windows in regimented form represent industrial production and simplicity. A curtain glass wall is essentially a wall that serves many functions of a window. 
Chandigadh India Le Corbusier Architecture of Windows

One of the ever increasing purposes of a window has been view out. These are now available from the modern window. 
1. A view unhindered by clutter of mid-members like mullions and transoms. 2. A view unrestricted in scale by the size of the glazing material. 3. A view unaffected by the colour tinge or impurities. 4. A view unaffected by the glare or shimmer. 5. A view that is one way or private. 6. A window singly curved and doubly curved to enhance the quality of view.
 The view-out functions are achieved at a great cost, but available up to a certain depth within a building. Inner areas are cut off from outside. A very efficient glazed building has to depend on HVAC means for climate control. A glazed entity cuts off the fresh air, odours, the varying external atmospheric conditions, sounds and noises of nature and surroundings. A glazed entity is a consistent reminder that inside is a restricted world, but outside even though not benign offers surprises. The architecture in coming years will be addressing these issues, with new forms of windows and perhaps architecture itself. 
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WILHELM SCHUBERT VAN EHRENBERG

  Post -315 . Sunday feature on ART of ARCHITECTURE -by Gautam Shah .  Wilhelm Schubert van Ehrenberg , was Antwerp based (1630 -1676) ...