SHADING DEVICES

RICHA MALIKAssistant Proffesor , B.Arch, M.Arch

ENERGY SIMULATION

AND THEIR IMPACT ON BUILDING THERMODYNAMICS

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Shading Devices

•The use of shading device is an important aspect of many high-performance building design strategies.• It has been proved that the use of shading device could improve building energy performance, prevent glare, increase useful daylight availability (between 100~2000lux) and create a sense of security.• Realizing these potential benefits, a varied of shading configurations have been invented and put in the market, such as fixed, manual and automatic movable, internal and external shading device. •Accordingly, many simulation tools have been developed to support shading design.

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Exterior shading device

•Exterior shading device is primary used to control sunlight penetration to the interior of buildings. •Such shading devices are always attached on the mullion as a separate component of building envelop, but can also be achieved by disposition of the building floors to create overhangs.

•Exterior shading device decrease direct beam penetration by projecting shadow on the window along the sunlit direction;

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Types of exterior shading device•Two basic types of exterior shading device are• Horizontal & Vertical• Various combination of these creates many configurations to accommodate different envelop shapes and orientations.

Each orientation of the building requires a different approach to the design of shading. The north elevation (in the northern hemisphere) essentially does not require shading because

except in the summer months in the early morning and late evening, no sun penetration occurs.

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-the length of the projection is determined as a geometric function of the height of the window and the angle of elevation of the sun at solar noon.- Such shading devices can be designed to completely eliminate sun penetration in the summer and allow for complete sun penetration during the winter when such is desired for passive heat gain.

Basic Shading Strategy for a South Elevation

Horizontal shading devices are suited to southern exposures. Roof overhangs can also easily be used to shade southern exposures on low rise buildings.

SOUTH SIDE ORIENTATION

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In order to obtain shading in the late morning and early afternoon when the sun is not at its high point, the shading device should be extended either side of the window opening.

Elevation of Shading Device Configurations for South

Facing Facades

SOUTH SIDE ORIENTATION

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The east and west elevations are both difficult to shade.In east direction we receives early morning sun and from west direction we receives evening sun Its angle is also low enough to preclude shading using overhangs.

Shading can be provided in the way of landscaping and foliage

Shading Devices for Non Southern Exposures

EAST AND WEST SIDE ORIENTATION

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Other shading devices

Besides attaching shading device on exterior of building envelop, many other ways can also prevent sun light from penetrating to the interior of buildings.•Interior shading device•Building self-shading•Shaded by trees and other obstructions

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Shading Devices in IHCThe reflectors are installed above the building to provide shade and prevent sun from entering into the building. The reflectors are aligned at an angle which reflect back 70% of the sunlight and change their angle during winter to allow sunlight to fall on the windows.

Sun shading devices are incorporated into the design of the facade and the overhanging floors of each level to provide sufficient shade to ensure a comfortable environment within the dining and office spaces

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Solar shading device for high-rise buildingsThe external shading system sits like a skin on the outside of a building, moving around on tracks to shield the sun while still allowing daylight to penetrate.

Made from a lightweight frame incorporating photovoltaic cells, the sunshield:•reduces the energy required to light and cool the building by 30%;•produces enough energy to power the movement of the shade and provide up to 10% of the building remaining power needs;•is made from a simple and cost-effective series of modular panels, which can be removed individually without compromising the whole system; and•incorporates a guide rail at each floor level to provide both structural support and access for cleaning and maintenance.

Solar Louvers minimizes glare & over heating

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Solar shading device for high-rise buildings

Dan M. Russell Jr. U.S. CourthouseTo support the U.S. Governments efforts to construct energy efficient buildings, this courthouse features C/S Sun Controls on five stories of this buildings southern elevation.

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