EXTERNAL or INTERNAL ‘REVEALS’ of OPENINGS

Post 685 –by Gautam Shah

.

6 French door in thin wall httpspixnio.como

Walls are chiefly load bearing entities. The thickness is the third dimension to the nominal planner structure. The third dimension has a functional depth, and architectural character. The Architectural expression of the wall-depth modulates the facade and gives a massing flavour. The functional depth frames the view, and regulates the illumination in the interior space.

2 Squared edge openings in Thick walls 32723717541_b24cbfb0ca_z

Openings in thicker walls have external or internal ‘reveals’ surrounding the frame. The bottom section forms the ledge of the sill. Openings placed on the outer face create deep an inner side or intrados (originally intrados meant, the inner curve of an arch or vault). Similarly openings placed on the inner edge form exterior side or extrados (originally extrados meant, the outer curve of an arch or vault).

15 Siuntio._In_the_halls_of_the_manor._-_panoramio_(1)

The deep interior sides, ifsquare-edged (at a right angle to plane of the window), made the perceived size of the opening smaller, then it actually is. This type of setting on interior sides, was not a major issue, where the room spaces were comparatively narrow, and so reflection from opposite walls was available. The narrow spaces were due to the technological restrictions and for functional requirements, such as in long halls and church buildings. In squared buildings the illumination was balanced from windows in the drum perimeter of the dome.

3 Abbaye_de_Silvacane_-_galerie_nord_06

The deep exterior sides, if square-edged (at a right angle to plane of the window), made the perceived size of the opening smaller, a desired arrangement to enhance the wall area and de-emphasize the presence of gaps of openings. It reduced the ingress of winds and snow-rainwater. To emphasize the presence of gaps, portals were added as the opening’s treatments.

9 Squared edge window_shadow_open_window_window_sill_wood-89674.jpg!d

The square’ edged openings have high contrasting brightness. Such windows require counter illumination to reduce the glare. To distribute the light better in the interior space, inner sides (-intrados with the window fixed on the outer edge) and an outer side (-extrados with the window fixed on the inner edge) were splayed by chamferring. The angled side surface was further carved, fluted with ornate borders or architraves.

1 3 M thick walls and chamferred internal edges of Guard room at Burg Meersburg on Lake Constance in southern Germany Wikipedia Image by Tobyc75

4 Canterbury_Cathedral_11

5 Norwich Cathedral 5987419099_94fe78d27d_z

Inner vertical sides, window heads and the sill, all were sloped to enlarge the reflective surface area. The chamferred sides on the outer face allowed more light by increasing the sky component, and allowed wider view of the outside.

20 Murals need evenly distributed illuminated wall Basilica di Sant Apollinare in Classe Wikipedia Image by Flying Russian

The effects of square and the chamferred sides of openings were well known to the mural artists (working with different mediums such as tempera, mosaic and frescoes painting), who accordingly composed the stories, shading in the scene, perspective angle, colour’s  hue and tone of artwork.

18 Dunstaffnage_chapel windows

14 Romanesque_church. panoramio Wikipedia Image by More pics than views…

In Romanesque and early Gothic architecture the windows were fixed on inner face, creating a plain and undisturbed interior surface. But by the time this was perfected, the Gothic walls were completely diminished, and windows were as wide as the gap between two columns.

Stained Glass in Windows

19 Basilica_di_aquileia,_interno,_navata_centrale_02_controfacciata

13 Exterior flush windows deep set on interior side Santa_Maria_in_Cosmedin-templom_belso

Side walls of Gothic buildings became thinner due to the arrangement of flying buttresses and use of load-bearing columns. But the same advantage was not available in case of un-buttressed Front wall. The entrance doors of Gothic churches were flush-set on the inner face, and that allowed better view across and fuller distribution of light. But the doors set deep in the thick walls, needed chamferring with serrated sides.

21 Chartres Cathedral serrated door portal .flickr.comphotos69184488 N061189397807

In Baroque architecture the depth of opening was concealed with the projected facade elements like columns, pilasters, cornices, or pediments. In Italian Renaissance the facade had an applique lattice like a pattern that united several openings. In post medieval period, windows began to protrude out of the buildings, over into the narrow street. Bay and oriel windows, Mashrabiya openings in the middle East, and Zarokhas in India transgressed out, mainly to gain sideways view and air. The multi sided mass of the projection became a personal statement.

8 Deep set openings Hindola_Mahal,_Mandu,_India

In post medieval period, window projections created serious fire hazards and issues of encroachment of public lands. Both of these were corrected through improved fire laws and defined easement rights. Fire laws required windows to be within the wall (without any projections like ledges or hanging shutters). Later the Window tax curtailed the number of openings in a building.

22 Openings

Gothic architecture had already shown how to divide large openings with traceries of mullions and muntins. Large windows in thin walls require framing and masking, but small depth did not allow formation of integrated architectonic elements, or scooping out for niche creation. Architectural add-on elements such as half columns, extrados, porticoes, etc. were additives placed to frame and highlight the opening.

24 Gothic window surfave articulated by Mullions, muntins in tracery 5987964570_01c2171afd_z

The surface of the window was strongly stated by articulated divisions, contrasts between glazed and other surfaces like rusticated masonry. Windows were also placed in inward or sunken bays. The mid-wall between the windows was treated as very shallow niche or bordered frame for murals, paintings or placing a fireplace or library cabinet. Building’s facades of thin walls were also undulated by outward bay windows, ledges and other projections.

10 Protected Opening Tim 1965 1601_I_Street_NW_-_Washington_DC_-_window_detail

Thick walls accommodate the shutters of doors and windows within the gap. But shallow window gaps offer no shading. Some form of external shading system is required. Such shading systems have been used for creating architectural facade system, as in Chandigarh Secretariat building.

16 Chandigarh_Secretariat

Glass curtain walls are thin body construction, often without any projections for solar protection. This now sought through the glass technology, and the ventilation through separate HVAC system. Thin walls save floor space, and so are economic in spite of the compulsory recourse to other compensatory facilities. The nominal architectural play of depth and shadows for 3rd dimensional visual depth is not available with openings in very thin walls. This is now recreated by volumetric play of the building mass, or by variegated surface finishes. For such surface modulation, other means include visual reflectance and glows (illumination from within).

Modern Windows Exterior Building Architecture

23 Industrial Age Window 6064685431_fd7d7b189c_z

The vividness of stained glass windows or the colourful lanterns of Gothic eras are now recreated through see through LED glass. At another level the touch screen provides the same fare. The mix of the two will become part of architectural and interior face of buildings.

26 Virtual Window 15370207660_617f953a34_z

.

Advertisements

PERCEPTION of CONTRAST -Issues for design -18

Post 659 -by Gautam Shah

.

Contrast is a deviation from the expected. It is the realization of a thing against, the obvious, existing, notional or ideological percept. Contrast is seen between nominal or obvious things, versus abnormal or non-perceived conditions. Like a full vs empty streets, clear vs fuzzy, pleasant smell vs unpalatable taste, dark-hot vs bright-cool, vibrating but noiseless; These are some such expectations vs perceptions.

st-pauls-cathedral-768778_640

Contrast is a comparison and occurs in some reference. The reference forming nexus is proffered in real or a hyper realm. But the ‘thing’ and its context are not always in the same space or time setting. Contrast makes a ‘thing’ stronger by juxtaposition of some weaker, duller or different elements.

grand-central-station-new-york-city-1957

Contrast is detected by two distinctive processes. The perception, is a combined experience of different sensorial faculties. And it is also a process of cognition that defines the strongest experience forming the main object or foreground, and all other as the background. The backgrounds offer the context.

paris-2499021_640

Sensorial faculties have their own scale of strength, and some have bipolarity. Typically eyes and ears continuously back up the space-position details. Similarly nose and tastes buds in the mouth, are closely located, and so show time-simultaneity in definition of edible things. The space-time references are filled in by other senses. Multilateral nodes of touch support such a process.

taj-mahal-1209004_640

The foreground-background divergence manifests in time-space reference. The juxtaposition, however, is not in the same space or time setting. The nexus could be in real or hyper a real realm. The hyper realm consists of experiences and resulting expectations. One has seen neither heaven nor hell, but both pose concurrently as extreme contrast. One of the two could be real and other through anecdotical knowledge. Here the contrasts are realized through recall. The contrast is relevant till foreground-background simultaneity remains within a fathomable range of perception. Architectural entities contrast in size, scale, style, placement, orientation, and environmental conditions, thematic content etc.

Chandigadh India

silhouettes-2395432_640

The contrast offers a scale. Objects forming the contrasting zones have shapes, extent, proportion, and indicate a direction. The depth is the obvious phenomenon of foreground-background differentiation. Other two dimensions of the scale are formed by the shape and its extent. The fourth dimension of reality occurs with vivid scenes. Here, if the background is dull or static, the foreground contrasts intensely. And, where the foreground is dull or rapidly varying, the particulars of things and happenings fail to register effectively. The perceiver becomes confused and disinterested, if ‘back and foreground’ elements fail to present relationships in terms of now-then, here-there, far-near etc. In Design, there is always a conflict between context and contrast, requiring equilibrium.

chicago-beans-401393_640

Contrast makes things conspicuous to attract the senses. And the contrast to be obvious, occurs with some reference. The reference is formed by a ‘thing’ that is stronger by juxtaposition of some weaker, duller or different elements, by its power of persistence in reality, and as a recall. Often clues are included in the composition for the recall. The clues could be similarities, leftover trails of the past happenings or subtle insertions relevant only to the person experiencing it or in that time and space. Other design elements that offer contrast include presence of directions, sequences, repetitions, occlusion by frames, thematic continuities, sensorial consistencies, associated fables and explanations.

red-mountains-1149759_640

A design has internal and external context. Internal contrasts are part of the designed entity, so within the ambit of real experience. External contrasts occur through the embedded or implied metaphoric clues for connection.

Poblenou-Contrasts

Architecture occurs in the context of its terrain, environment and stake holders (humans and tasks) and incorporeal parameters like weather, culture, economics, social and politics. These are universal posers, some find them suffocating in creation of outstanding and long-lasting contrast. So contrast is realized by negation of the contextual elements. Architects resort to attitudes like deconstructivist, monumentalist, eccentricist etc. Architecture has been for a very long time and substantially static formation, but now for evocation of contrast, not only the form is made dynamic but the perceiver-users are made mobile and hyperactive. These experiences began in rapidly changing environmental conditions, unsettled positions of perceptions, gyrating conditions, gravity less conditions, videos and movies.

crowds-2768571_640

In art work like paintings aberrations of perception arise from how spaces are postulated by extent and depth, and time is suggested with metaphoric details. The way colours are seen or weights are felt is due to such contrasts. Our past experience and desires make us see or experience things before they happen at closer locations.

the-fog-2721653_640

A silhouette is a very specific condition of contrast. Here the proportion of dark-light is of course important, but the edge conditions like shapes, arrangement, sizes etc. determine the effectiveness of contrast. Silhouette work in two ways: One due to the stark difference between the background and foreground, and Two due the lack of details in the foreground object. A glare is a form extreme contrast which fuzzes the foreground.

Vatican Silhouette

Camouflage is in a way opposite of contrast. It forms from the skillful exploitation of the contrast, though the resultant scenario is cacophonous. The noise occurs from anomalous conditions between the perception and its cognition. It is also the difference between real experience and the expectations. Camouflage morphs the foreground with background, alternatively the foreground turns fuzzy due to the reflections, multiple impressions, askew positioning, colour intonation, altered scaling etc.

219634617_2e6dafdb2b_z

Contrast occurs due to cascade of light, glare, echoes or reverberation, masking (of smell, taste), screening, covering, hiding reflections, and framing.

beach-1846082_640

Cascading Light and camaflauge

Protective scaffolding over Taj Mahal AgraIndia 1943

Uniform colour

This is the 18 th article of 20 topics series on ISSUES for DESIGN

.

 

BLOGS LINKS about PERCEPTION

Post 652 -by Gautam Shah

.

These are my select few 91+ blogs (out of nearly 850 placed on my 4 blog sites) written over last 4 years, now compiled under a common theme ‘Space Perception’ with following sub sections.

      0  New series of Lectures (Four) on Perception

  1. SPACE PERCEPTION
  2. ILLUMINATION
  3. MOVEMENT, BALANCE
  4. OPENINGS SYSTEMS
  5. GLASS
  6. GRILLS, TRELLIS, CURTAINS
  7. SOUND and NON VISUAL
  8. OBJECTS, SURFACES, COLOURS, PATTERNS
  9. REALITY, MAKE-BELIEVE

 

4699879751_a6efd82383_z(1)

0  New series of Lectures (Four) on Perception

0.1 SOME SOUND BITES -Space Perception -I

https://designacademics.wordpress.com/2018/02/12/some-sound-bites-space-perception-i/

0.2 STRATIFICATION of VISION

https://designacademics.wordpress.com/2018/03/02/stratification-of-vision0.2 /

0.3 PERCEPTION of SPATIAL FIELDS -ILLUMINATION

https://designacademics.wordpress.com/2018/03/11/perception-of-spatial-fields-illumination/

0.4 MULTI NODAL PERCEPTIONS of OBJECTS in SPACE

https://designacademics.wordpress.com/2018/05/14/multi-nodal-perceptions-of-objects-in-space/

 

 

1 SPACE PERCEPTION

1.1 PROCESS of PERCEPTION

1.2 PROCESS of PERCEPTION part-I

1.3 SPACE PERCEPTION -through seeing, hearing and touching

1.4 SPACE PERCEPTION – Issues for Design -4

1.5 SPACE PERCEPTION

1.6 SPATIAL DEFINITIONS

1.7 SENSING OBJECTS BEYOND THEIR SIZE MEASURES

1.8 SPATIAL DEFINITIONS

1.9 SPATIAL DISTANCING and BEHAVIOUR

1.10 DISTANCING in SPACE

1.11 SPACES SIZES and SHAPES

1.12 SMALL SPACES and LARGE SPACES

1.13 REACH in SPACE

Scaffold Building Manhattan New York City Taxi

2 ILLUMINATION

2.1 CONTRAST EFFECT – PERCEPTION

2.2 PERCEPTION of SPATIAL FIELDS -ILLUMINATION

2.3 DAYLIGHTING

2.4 DAY-LIGHTING – in Interior Spaces

2.5 DESIGN CONSIDERATIONS for DAYLIGHTING

2.6 SPACE PERCEPTION and ILLUMINATION

2.7 DAYTIME INTERIOR ILLUMINATION -REALITY and PERCEPTION

2.8 INTERIOR ILLUMINATION through DOORS

2.9 WINDOW LOCATION and NATURAL LIGHTING

2.10 LE CORBUSIER and ILLUMINATION

2.11 COMPARING WINDOWS of FLW, LC and Mies

ac263ca3-836c-4a10-8cea-78b8cf487224

3 MOVEMENT, BALANCE

3.1 MOVEMENT and BALANCE – Issues for Design -5

3.2 PERCEPTION of BALANCE and MOVEMENT

3.3 BALANCE in DESIGN – Part 1

3.4 BALANCE in DESIGN – Part 2

3.5 VISUAL PERCEPTION of MOVEMENTS

3.6 PERCEPTION through SCALES and CONVERSIONS -Issues or Design -3 

Landscape

4 OPENINGS SYSTEMS

4.1 LEVELS of OPENINGS

4.2 DESIGNING OPENINGS

4.3 CLASSICAL WINDOW FORMS

4.4 ARCHITECTURAL WINDOWS and VISION in-out

4.5 ARCHITECTURAL WINDOWS and the MEANING

4.6 ARCHITECTURAL WINDOWS and MECHANICS of VISION

4.7 MEANING of a WINDOW SILL

4.8 THIRD DIMENSION of OPENINGS

4.9 LANTERNS in ARCHITECTURE

4.10 CLERESTORY OPENINGS

4.11 SKY LIGHTS

4.12 ROOF LIGHTS

4.13 SHOP WINDOWS

4.14 SHOP WINDOWS – SHOP FRONTS – DISPLAY WINDOWS

4.15 FRAMING of OPENINGS

4.16 MASKING of OPENINGS Part -III -Framing

4.17 MASKING of OPENINGS Part -II

4.18 MASKING of OPENINGS Part -I

Eating_Alone

5 GLASS

5.1 GLASS in ARCHITECTURE -1

5.2 GLASS and PERCEPTION

5.3 GLASS in WINDOWS – Part • I

5.4 GLASS in WINDOWS – Part • II

5.5 COLOURED GLASS

Fixing Metallic Transparency Glass Front Metal6 GRILLS, TRELLIS, CURTAINS

6.1 CONTEXT -Issues for Design -12

6.2 ROOFS 3 -Skyline and Silhouette

6.3 HOLISM and DESIGN

6.4 TRELLIS

6.5 GRILLS

6.6 CURTAINS

6.7 TRANSLUCENCY for CURTAINS

6.8 SHEER FABRICS and CURTAINS

6.9 SHEER FABRICS and CURTAINS-2

6.10 NON SILK SHEER FABRICS and CURTAINS

6.11 WEIGHT and TRANSLUCENCY of fabrics for curtains

6.12 SHEER FABRICS

Religious Kneeling Worship Pray Prayer Church

7 SOUND and NON VISUAL

7.1 SOUND

7.2 SOUND, SPACE and PERCEPTION

7.3 PERCEPTION of SOUND and SPACES

7.4 SPACE and SOUND REVERBERATION

7.5 SOUND and NOISE MANAGEMENT

7.6 HEARING and interior spaces

7.7 ACOUSTICS in SMALL SPACES

7.8 SOUND and SMALL SPACES

7.9 SPACE PLANNING and NON VISUAL CUES

7.10 NON VISUAL LANGUAGE -Issues for Design -6

7.11 LANGUAGE EXPRESSION and SOUND PERCEPTION

wuzhen-1643267_6408 OBJECTS, SURFACES, COLOURS, PATTERNS

8.1 OBJECTS in SPATIAL FIELDS -Issues for Design -14

8.2 COLOURS -Perception and Expression

8.3 COLOURS and BUILDINGS

8.4 FLOORINGS

8.5 FLOORING COLOUR

8.6 FLOORINGS IN INTERIOR SPACES

8.7 PERCEPTION of SURFACE FINISHES

8.8 GLOSS

8.9 TEXTURES and MATERIALS

8.10 JOINTS in SURFACE FINISHES

8.11 MOSAICS

pexels-photo-327496

9 REALITY, MAKE-BELIEVE

9.1 SOLIDS and VOIDS -issues for Design -13

9.2 AUGMENTED REALITY

9.3 SPACES and REALITY

9.4 MAKE-BELIEVE in INTERIOR DESIGN

 

640px-Ave_Maria_Weihnachtskrippe

.

SPATIAL NATURE of WINDOWS

Post 644 –by Gautam Shah

.

Windows are surface elements with great presence on both exterior and interior sides. It is fairly a complex entity against the comparatively simplistic wall, but a surface that is penetrable. Its surface is very dynamic, due to the continuous variations in views through it and the vivid reflections on the glass surface. The contextual conditions like climate, illumination, distance and angle of observation and the purpose of use and multifarious position of the shutters continuously reshape the perceived form of the window.

The external changes are reflected as a reverse mirror image in the glazing surface, and the interiors get revealed through an iridescent surface. A window, as a single picture frame, simultaneously reveals the changes occurring in the interiors as well as exteriors. The dynamism of the window gets enhanced further by the framing, masking and filtration of the perception.

12043141995_7cea888961_z

Looking out Chand Baori Stepwell Rajasthan India Flickr Image > https://flickr.com/photos/bpprice/12043141995

A window is like a membrane with degrees of permeability. It may not permit one to go through it, but allows to stretch out through the sensorial faculties. We see, smell, listen and feel the other side through the window. The connection to the other side of the window is always short and casual. The frugal experience stimulates one to go across it, albeit by other means. Doors are dilemmas, either go out or remain in, but a window provides no such options. A person on outside of a window perceives the safety in the interior, and the one in a bounded space realizes the freedom and diversity of experiences available outside. Windows have been used for opening out the interior spaces or for bringing in the exteriors.

Pecs Zsolnay Architectural District Building

The historical window with opaque glazing of heavily coloured pot glass was extremely colourful but dead static. As the glass became thinner and lighter in colour, the changes in outside levels of illumination began to be noticed on the interior face. This was aided by the use of water white Cristallo glass. Interiors seemed now much more natural, and attuned to the outside changes in luminescence. Till 19th C windows were vivid elements in an otherwise static exterior or interior surface. The Cristallo glass, outside was a dull metal like an opalescent surface, but new clear glass with better casting, polishing and fire finishing began to be iridescent.

The glass was recognized as having two distinctly different faces. Iridescent on the outside face due to reflections and a ‘water-white’ flawlessly clear and non glossy surface on the interior face. Corbusier used the opaque iridescence of the exterior surface to juxtapose the exterior masonry or cement surfaces. But FLW used the deep shadows to eliminate the exterior iridescence and added colour staining and patterning to break the transparency. Mies used the exterior mirror like gloss to reflect the changes occurring in the surroundings concurrently juxtaposing the interiors. This helped to reduce the massiveness of the built-form.

4669546266_c5b82b6634_z

FLW Window with masking of Pattern > Flickr Image by Hardisty

Window glass is now often used to assimilate the realities of interior and exterior on a very large joint-less screen. The mix creates a very vivid object, like a water body reflecting both the sky and the floor. Metalized opaque glass belies the two-way transparency of a see-through element.

Wall to wall glass openings dissolve one or many sides of a volumetric space, reshaping its perceptive size, scale and extent. The spatial illusion becomes more intriguing when such a large reflective glass surface is used. Wall corners, large stretches of surfaces, acutely angled spaces, stubborn elements like columns and piers are dissolved by illusion of windows through mirroring effect of glass.

4889566212_582d401609_z

Corner in Glass > Flickr image by Wonderlane > https://www.flickr.com/photos/wonderlane/4889566212

We are conditioned to expect certain spatial effects in a space. And glass is an effective tool for breaking that anticipation. A narrow space visually gets widened by a glass opening. Skylights and clerestories add ‘lightness’ to the space. Lights such as roof holes focus the attention. Openings, depending on their location and nature redefine the space configuration. The stratification of view to the outside offers different scale to the space. Significantly bright areas highlight the details, and so are perceived and registered, more effectively then darker zones. A window becomes an element for changing a space, intentionally and accidentally.

madrid-1493002_640

Madrid Crystal Glass palace Pixabay image by IvanPais Espanol

madrid-1493003_640

Madrid crystal glass palace > Pixabay image by IvanPais Espanol

Windows are furrowed gaps into an otherwise solid barricading mass. The depth is highlighted due to the dark interior, and shadows cast by strong and directional light. The shadows as a form creating element was very well exploited by L. Kahn in his Asian buildings. The same effect at a micro scale and in repetition creates a lattice, used in Indian Architecture. Windows like, bay, bow, Mashrabiya and oriel have been used to enlarge interior spaces and also to correct the interior shape of the space. Zarokhas add to the interior space but have also been used to undulate the exteriors.

7511302668_ae54781fac_z

Gothic window tracery Snettisham Norfolk England > Flickr Image by Spencer Means > https://flickr.com/photos/hunky_punk/7511302668

Masking has been very commonly used to change the character of the windows. Greek and Roman architecture subdued the openings as a secondary and less visible layer. Romanesque windows once again came to the surface, but openings were framed by the semi circular arch. Coordinating several windows was a difficult design issue, as the height of the rounded arch was defined by the width of the opening. Gothic architecture solved the problems of geometric composition, by of pointed arch. It also created a system of subdividing the window opening through mullions, transoms and glazing bars. The window opening was masked by traceried patterns. Window masking became an effective tool to overcome the deficiencies of glass, size, clarity and impurities. The deficiencies made the windows subservient entity of the load-bearing structure. Glass houses, orangeries, etc. allowed windows to define a space without the use of a wall. The need for very large and deep sun lit spaces for bus depots, railway stations, markets, and factories redefined the Windows’ spatial nature.

Stained_glass_window_with_the_Parable_of_the_Prodigal_Son,_France,_c._1215-1225,_pot_metal,_glass,_vitreous_paint_-_Krannert_Art_Museum,_UIUC_-_DSC06358

Pot Metal Glass stained Window Exhibit in Krannert Art Museum > Wikipedia Image

Framing is a property of all openings. Openings have their sides and mid members within the view cone depending on the point of observation. Palladio masked and framed the exterior face of the opening. The double-hung sash windows did the same on both, exterior and interior face. Framing is now used as an inevitable joint management system, and but often made imperceptible. Stratification (window openings’ position @ low, mid or higher level with reference to height of the user or the task plane) is an important ergonomic parameter that affects the spatial perception.

1-1024px-Elgin_Cathedral_south_aisle_windows

Elgin Cathedral > Wikipedia image by Billreid

Transparency is a quality of the glass, and the most important aspect of the surface of the opening. A window opening in the form of a glass curtain wall or shop front, shows up the space in its exterior surface configuration, and also the spatial depths of its interiors. The simultaneity of the exterior and interior spaces adds to the dilemma of the physical reality vs the virtual reality.

1-640px-Glasshouse-philip-johnson

Glass house by Philip Johnson New Cannan, CT USA > Wikipedia image by Staib

This re-composed article is based on my earlier BLOG > here >

http://talking-interior-design.blogspot.in/2009/12/spatial-character-of-windows.html

AND the BLOG was based on my Lecture Notes > Interior Components and Systems: Windows >>

http://www.gautamshah.in

.

 

DESIGN CONSIDERATIONS for DAYLIGHTING

Post 593 by Gautam Shah

.

Daylighting is illuminating the interiors of built spaces with the sunlight, as available during the sun up period. This is controlled entry of natural light and diffuse skylight into a building to reduce electric lighting and saving energy. The ‘direct’ daylight arrives through openings like doors, windows, skylights and other gaps. Indirect daylight is brought in as Diffused sky light from surface reflectors or Transmitted light through tubes and other devices.

23605499395_1541432f92_z

Haveli Courtyard, Near begum Samru’s palace > Flickr image by Varun Shiv Kapur

Daylighting depends on the external conditions, such as the season of the year, climate, dust, fog or cloud cover, time of the day, terrain or surroundings. Daylight can be designed through buildings, size (spread or massing, depth, floor heights), form or shape, orientation, scheduling and location of tasks, configurations of openings, etc. It is closely linked to saving energy used for lighting during daytime. Daylight is substantially dependent on openings like doors and windows, and this help creates stimulating and natural environment.

india_airport

Chhatrapati Shivaji International Airport Mumbai Departure area > Wikipedia image by Nancy Beaton

Daylighting is dependent on external conditions. The season of the year determines not only the ‘sunshine’ days and brightness, but the direction (solar inclination) of the light. The climatic conditions govern if fenestrations can be kept fully open or closed. Local atmospheric conditions like dust, fog, cloud cover and pollution affect the intensity of daylight. Activities must be scheduled according to the diurnal cycle and positioned as per the available exposure. The surroundings’ factors, such as the terrain slopes, colour (of white sand beach fronts, green lawns or foliage, water bodies), and reflective capacities determine the brightness level of illumination.

640px-libya_4432_ghadames_luca_galuzzi_2007

Sahara Town Ghadames Libya > Wikipedia image by Luca Galuzzi http://www.galuzzi.it

Daylighting and building design, have mutual dependence. The exposure of the face, surface area, perimeter and form of the buildings can be advantageously exploited for better gain of daylight.

Daylighting for energy saving must be conceived with a view to reduce the artificial illumination requirements of deep-set spaces, low height spaces, isolated interior entities like vestibules and corridors. A synergetic system to calibrate the electric illumination can be created for task-need and occupancy of the space, compensative distribution (elimination of glare-contrasts) and low heat output.

640px-abbaye_d27acey_30

High sill windows Abbaye d’Acey Jura France > Wikipedia image by Arnaud 25

Fenestrations and Daylighting are linked. Fenestration location (wall, skylights), height, shape and construction affect the daylighting. Fenestrations also serve the purpose of comfort (ventilation requirements such as heat gain-loss, air-moisture control, interior pollutant dilution, air movements) and view in-out, so must incorporate these requirements.

.

Daylight used for illuminating interior spaces, exploits the ever-changing quality in terms of intensity, colour and direction of the light. The daylight-design, scatters the light over a wider extent, diffuses its intensity and subdues the strong directionality, alters the colour quality, and shifts the location of the source.

prostitutes_peeking_out_from_the_doorways_of_their_brothel_in_lahore_in_1946

Screening for daylight and view Wikipedia image by Margaret Bourke-White

Light intensity is a function of season, orientation and fenestration design. These are important considerations for siting an activity. Light intensity is perceived against the brightness level of the background scene or the surfaces. It can also be altered by illumination from other directions or additional artificial sources.

640px-teaching_centre_interior2c_university_of_essex

Tony Rich Training Centre Uni of Essex Consistent illumination by skylight and support by electric light> Wikipedia image by Rwendland

Colour of the daylight as reflected sky component have small colour variations, except the occasional colour scattering at sun rise and set periods. Daylight received from reflected surfaces such as terrain, near by buildings and plants has a colour tinge. The colour of the glazing material, colour of the opening cover systems like Venetian blinds, curtains, overlay films, etc. side-surfaces of fenestration systems.

15397756655_8e394e1676_z

Colours of the surroundings > Flickr image by Darron Birgenheier

Direction of the light is an important consideration for ingress or avoidance direct sunlight. North light (South light in S-hemisphere), are designed to access best natural illumination for industrial plants. East side facing openings allow ‘cool’ brightness in comparison to West faces.

light-842447_640

Darker surface does not equalize the light > Pixabay image

Scattering the light over a wider area achieves equal brightness by avoiding high-low contrast or patchy areas. This is done by multiple openings or by masking the opening with diffuser screens. Scattering is avoided where dramatic effects are intentionally created such as vestibules, entrance halls, etc. Equalization of illumination in space is also achieved by electronic sensors that activate electric illumination in required intensity.

640px-taliesen-drafting-studio

Taliesin West drafting studio illumination > Wikipedia image by Steven C. Price

Diffusing the intensity of light is resorted to reduce the high level of brightness on summer or clear sky afternoon periods. This is done by automatic masking devices or by baffles or louvers with apertures attuned to non-bright exposure-directions and schedules. Diffusers are also used to reduce the level of brightness in areas that act as transition spaces to darker environments such as auditoriums.

window-light-659473_640

Strong light source and contrast > Pixabay image (of woman by window)

Calibrating a strong sense directionality with illumination is necessary to reduce the dynamism of direct natural illumination. Architectural openings like doors and windows bring in variations of brightness (movement of clouds), shadows of moving objects (trees, vehicles, other traffic), and variations of colours into the interior spaces. This changeability is often an irritant for work areas like laboratories, libraries, bedrooms, etc. By sourcing the daylight from multiple directions, the illumination can be made static and multilateral.

640px-wells_cathedral_hdr_photo_28226440155329_golden_window_crop

Contrast reduced by additional illumination from side openings >Window at the East end of Choir in Month of Feb, Wells Cathedral Somerset > Wikipedia image by IDS.photos from Tiverton, UK

Altering the colour quality where colour perception is important such as in surgical and pathological areas of hospitals, colour and dye manufacturing plants, film and media editing rooms. Here not only the colour must be neutral but consistent. This is achieved by avoiding light reflected from external sources, such as pavings, walls and lawn or green foliage.

Shift the location of the source is important for space planning design at micro level. The available natural source may have strong left or right, up or down delineation and may need the shift of illumination location. This is done by external and internal reflecting surfaces or use of light transmission tubes.

.

DAYTIME INTERIOR ILLUMINATION -REALITY and PERCEPTION

Post 486  by Gautam Shah

.

Landscape Lattice Ceiling

 

Illumination is required in interior spaces in several contexts. At realistic level, task illumination is the most obvious requirement, but one needs sufficient illumination to move around known as well as unknown interior spaces. At perceptual level an illuminated space is associated with cleaner and healthier space. The perception has been so ingrained into our psyche that interior brightness and well-being of the space as one concept. For ages, in absence of glass, openings were ‘open’, allowing sufficient ventilation through the cracks and gaps in the door or windows. And even when openings began to be glazed, the sunlight seeping through it warmed up the interior space to cause air movements, and act as bactericide.

door-open-666175_640

 

USCapitol_-_Capitol_Visitor_Center_Skylight_-_U.S._Capitol

In Northern hemisphere, the North, and in Southern hemisphere the South, gets solar exposure throughout the day. And so, at realistic level, the North and South facing openings are chosen for illumination in factories, schools and homes. But perceptively, it is the East, than west, or combination of both, have found favour, for religious buildings. East-west light is nearly horizontal in the morning-evening and penetrates deepest section of a building. It is varying hour by hour, unlike the consistent North-South light. East-West light is dynamic and awe inspiring. In early Egypt the Sun god was revered and the main doors of temples were East facing. North and South doors have high inclination of the sun, so horizontal penetration of illumination is not very deep.

West front of Wells Cathedral UK

skylight-692214_640

Door orientation has a direct bearing on the level of illumination. Early Church buildings had Eastern entrances to illuminate the altar from front, but an altar with an Eastern back-lit glass windows proved to be a better alternative. Gradually churches began to have Western entrance doors. The East-West have been prime directions for illumination in many historical buildings, however, with the ascent of the clear storey openings the importance of a door as the chief illumination provider has decreased.

egypt_temple_temple_complex_hieroglyphics_nile_historically_pharaohs-1276297.jpg!d

The size and Width-Height proportions of a door have a direct relationship with the depth of illumination. A taller door is more effective then a wider door in illuminating deep interiors. Monumental buildings have tall doors not just for architectural grandeur, but the upper section of a tall door provided the deep illumination during a crowded ceremonial function. In Egyptian temples the upper section of the door was supposed to bring in the Sun god with the first rays of rising sun. The tall doors were unmanageable for shutter mechanisms and also too narrow for ceremonial passage. The upper section was either left without a shutter, or latticed to form a ‘transom’. It was more practicable to leave a transom or a rose window than load a wall over the door lintel.

Inside_one_of_the_rooms_of_the_Rang_Mahal

The illumination through a door has also been enhanced by providing side lites or sidelight and also ‘within the door’ with lattices. Greek buildings had panelled doors that were partly latticed in the upper sections, or had additional latticed shutters. Side lights or side windows decrease the size of the shutter and reduce the structural span of the lintel, but increase the perceptive width of the opening.

Shipping Warehouse Bay Industry Storehouse

Illumination through a door invariably accompanies the radiation. The solar radiation through a door varies depending on the geographical location, orientation, time of the day, shading devices, nature of the foreground and surroundings, etc.

Puerta del Perdón, Catedral de Toledo, España Pic by Sevillista on Flickr

The depth of the door (depth of the wall) defines the quality of illumination. A door in a very thin wall (Gothic architecture) -the flush set door, allows fuller distribution of light, (a larger segment of brightness on the inside), but a deep-set door curtails the brightness due to the sides of the wall. In Gothic cathedrals due to side buttressing the side walls were thin and allowed flush set openings (with stained glass), but the same structural advantage was not available in case of un-buttressed front walls. The entrance doors of Gothic churches were deep set in thick walls but with serrated edges. Door sides (i.e. wall sides) and heads have been chamfers cut, on inside or outside faces, to enhance width and height. Chamfered edges on outside make the opening flush on the inside wall, and allow wider perception of the outdoors. A bevelled edge on the inside, make the opening flush on the outer edge of the wall. It allows visually more perceptible brightness on an interior surface due to the additional lit surface of the bevelled faces.

lonely_man_pub_person_adult_male_thought_thinking-825743.jpg!d

.

DAY-LIGHTING – in Interior Spaces

Post 366 – by Gautam Shah

.

Juma_Mosque_20140927_Uzbekistan_0284_Khiva_(15638472913)

Day-lighting or daytime natural illumination is an important requirement for Interior spaces. The illumination requirements vary for various tasks, background brightness (contrast or glare), forms of shadows, and movement or variations in levels of lighting. The direct sources of daytime natural illumination in interior space are openings like doors, windows, gaps, cracks, punctures, translucent or transparent walls, trellis, etc. Besides these there are number of indirect means that enhance or contrast the direct sources of illumination. These means are planer or curvilinear surfaces, reflective surfaces, colours and textures. The daytime illumination arrives to a built-form, from different directions and sources, such as directly from the source, from sky, and as the reflections from terrestrial objects. These sources include, direct sunlight, diffused sky radiation, and both of these as reflected from the terrestrial objects.

Kerala_courtyard_with_planter

The amount of daylight received into an interior space is defined as a daylight factor (being the ratio between the measured external and internal light levels). The external light level can be as high as 120,000 lux at noon for direct sunlight at noon, to less than 5 lux on very heavily cloudy evening.

pexels-photo-745240

To gain maximum daylight into an interior space the building should have wider foot print and its perimeter should be linear or undulated. The building must be longer in North-South direction, compared to East-West direction, unless the space is meant exclusively for either Morning or Evening use. For Northern Hemisphere, North side and for Southern Hemisphere, the South side receives more daylight.

640px-Interior_of_St._James_Cathedral

The neighbourhood buildings and topography and immediate surroundings have a bearing on the quality of illumination entering a building. The reflected light from surfaces of buildings, colours of roads and pavements affect lower floors of the buildings. Reflections from sea front and movement of trees tops, due to the breeze, can have unsettling effect on interior spaces. Upper floors of tall buildings, except in similar localities, receive consistent, but very strong daylight from nominal windows. Such floors with bottom windows get disturbing reflections from traffic and other movements, reflected to the ceiling.

railway-station-1653817_640

Location of openings, their proportion to wall, and distribution, determine the distribution of day light in the interior space. In tropical climate zones and in colder climes during warmer months, open doors play a very important role in daylight gain. Similarly, open to sky Chowk or cutouts with surrounding passages or ‘livan’ like spaces allow distributed illumination.

church_benches_rows_of_benches_plenty_of_natural_light_gothic_style_vault_rustic_interior_view-760176.jpg!d

For good day lighting the interior spaces must have at least one face with exterior exposure, or with an abutting shading component like verandah or gallery. A skylight or upper level opening is an efficient source for natural illumination. A taller window leads the daylight deeper into the room space. The depth of daylight penetration is approximately two and one-half times the height of the opening.

High – performance glazing with downward inclination

The space planning of an interior layout must be optimized for daylight. Large tall pieces of furniture can act as mid space barricading element or as reflective surfaces. In commercial spaces half or fully glazed partitions can allow just sufficient illumination for passage areas. A plain ceiling at low level may not be as reflective as a stepped or contoured one.

pexels-photo-189215

On exterior and interior sides use of light-shelves, against an opening, helps distribute the daylight and cut glare. A light shelf could be a small width blade of a louver to very large fixed or adjustable jalousie system. A high-performance glazing systems generally admit light without the heat gain.

morocco-2435391_640

Reflectance of room surfaces impacts the perception of brightness in a space. The surface reflectance is a function of colour, its texture (matt, dull-sheen, glossy) and the orientation of grains of textures. Extreme levels of brightness are present in the same field of view, can be calibrated by surface design.

Ahwahnee_Dining_Room

Daylight must be planned and ‘attuned’ for requirements of tasks, posture, communication, expression and intra-personal relationships, Poor visibility, recognition, and discomfort result from lack of required levels of illumination, direction. To remove wearisome consistency (as with sky or high level openings), some variations in moment to moment daylight must occur.

2329613513_0b221d6ac1_z

.