Inflow of sun’s radiation, securing lighting, and ventilation are traditional functions of window in building. However, people of modern society spend most time of the day indoors, so architects concentrate on not only functions of existing window but also raising of psychological comfortability by that window is expanded and then boundary between indoor and outdoor is knocked down so the outside view is expanded. Especially, in case of the coastal area, it is easy to find building having high area ratio of window to survey sea.
However, indiscreet expansion of window causes excessive inflow of sun’s radiation in summer time and consumption increase of air-conditioning and heating energy by high once through ratio of heat, and even brings about a breakdown of glass and scattering phenomenon of high-rise building by typhoon and gust. Moreover, building of the coastal area is in a particular environment like sea in comparison with building of inland area, so interference of surrounding structures is rare. Therefore, building in the coastal area is exposed directly by typhoon and gust. And, there is resident’s displeasure by increase of cooling road and glare by a sea fog, sun’s radiation reflected by water surface, and reflected light of water surface.
Therefore, this study deducted size of window that universal people can be satisfied with assessment of openness through experiment to prevent expansion to indiscreet size of window in building by occupants’ increase of indoor hours of living in modern society. Also, air-conditioning and heating load and natural lighting were analyzed according to size and shape of window with ECOTECT and RADIANCE Simulation.
The results of this study are as follows.
1) As a result of calculating wind load of windows and doors according to size of window, the greater area ratio of window increases, the greater design wind load increases, and the more ratio of available glass area decreases in comparison with the whole glass area.
2) As a result of measuring sensational quality according to size and shape of window, in case of that area ratio of window is under 50%, the bigger window grows, the greater subject’s perceptual capacity and psychological comfortable sensation increase, and about same size of windows, the window whose horizontal width is long shows the result price higher than the result price of the window whose vertical height is long. However, in case of that area ratio of window is more than 60%, the bigger window grows, the greater perceptual capacity increases, but the more psychological comfortable sensation decreases.
3) Air-conditioning and heating load increased in proportion to increase of window area ratio, and heating load of Case A is lower than heating load of Case B, but cooling load of Case A is much higher than cooling load of Case B, so the whole load of Case A is higher than the whole load of Case B. Case A whose horizontal width is longer can reduce heating load in winter because inflow of sun’s radiation of Case A is more profitable than inflow of Case B, but in its final analysis, it is the result by that increase of solar heat gain through window in summer causes increase of the whole load.
4) In case of illuminance distribution on the surface of indoor floor according to area ratio of window in winter solstice(December 21st), it is impossible to satisfy standard illuminance in 5p.m. of the day independently of size of window, but area ratio of window whose ratio of floor area belonging to 400 to 2000lux of the effective illuminance scope is the highest is 50 to 60 in Case A and Case B.
As a result of putting each study results of stability, assessment of openness, air-conditioning and heating load, and natural lighting about wind pressure of window together, majority of subjects was satisfied with 40% of window area ratio and felt the most satisfied in 60% of window area ratio. Design wind load and air-conditioning and heating load increased in proportion to increase of window area ratio, and in case of interior illuminance, there was the broadest floor area belonging to 400 ~ 2000lux of the effective illuminance scope in 50 to 60% of window area ratio. Also, in accordance with standard related with setting-up of domestic size of windows and doors, 50 to 60% of window area ratio is the standard of the biggest window area ratio. Therefore, in consideration of assessment of openness, consumption of interior energy, and related standard, the most effective scope of window area ratio is 50 to 60%.