The four fundamental shading strategies. The use of appropriate solar controls is very important, especially within air-conditioned buildings. Proper shading greatly reduces what is essentially a needless waste of energy trying to cool a space with large areas of unprotected glazing. The diagram above indicates the four fundamental shading strategies available to you. It is essential that the designer understand the advantages and disadvantages of each in order to select and apply them correctly. 7.0 OVERSHADOWING Annual patterns of overshadowing can be visualised by plotting the outlines of obstructing buildings and vegetation on to a . This produces what is known as the solar aperture - being that area through which a particular point can 'see' the sky. Imagine lying on your back looking through a full 180° fish eye lens pointing straight up towards the zenith of the sky. The image you see would be very close to that shown immediately below. If the path of the Sun through the sky was then overlaid, it would be possible to tell when in the year you would be in direct Sun and when you would be in shade by simply determining when the Sun was obstructed by objects in the surrounding environment. Diagram showing a photograph of the entire sky dome taken through a 180° fish-eye lens and how the sun-path and solar aperture is defined. To construct such a diagram, consider an imaginary hemisphere surrounding some point - usually termed the Focus Point. Areas of Sun blockage are determined by projecting lines out from this point to vertexes on the silhouette of each object and determining where they intersected this imaginary hemisphere. The resulting shapes on this hemisphere can then be transferred to a sun-path diagram. Any area of shadow in the resulting diagram represents an area when the Focus Point is in shade, where an object would block light from the Sun when it is behind it. Diagram of a simple solar window projected onto an imaginary hemisphere around an object. From ECOTECT From RADIANCE Examples output of computerised 3D shadow projection.
The four fundamental shading strategies. The use of appropriate solar controls is very important, especially within air-conditioned buildings. Proper shading greatly reduces what is essentially a needless waste of energy trying to cool a space with large areas of unprotected glazing. The diagram above indicates the four fundamental shading strategies available to you. It is essential that the designer understand the advantages and disadvantages of each in order to select and apply them correctly. 7.0 OVERSHADOWING Annual patterns of overshadowing can be visualised by plotting the outlines of obstructing buildings and vegetation on to a . This produces what is known as the solar aperture - being that area through which a particular point can 'see' the sky. Imagine lying on your back looking through a full 180° fish eye lens pointing straight up towards the zenith of the sky. The image you see would be very close to that shown immediately below. If the path of the Sun through the sky was then overlaid, it would be possible to tell when in the year you would be in direct Sun and when you would be in shade by simply determining when the Sun was obstructed by objects in the surrounding environment. Diagram showing a photograph of the entire sky dome taken through a 180° fish-eye lens and how the sun-path and solar aperture is defined. To construct such a diagram, consider an imaginary hemisphere surrounding some point - usually termed the Focus Point. Areas of Sun blockage are determined by projecting lines out from this point to vertexes on the silhouette of each object and determining where they intersected this imaginary hemisphere. The resulting shapes on this hemisphere can then be transferred to a sun-path diagram. Any area of shadow in the resulting diagram represents an area when the Focus Point is in shade, where an object would block light from the Sun when it is behind it. Diagram of a simple solar window projected onto an imaginary hemisphere around an object. From ECOTECT From RADIANCE Examples output of computerised 3D shadow projection.
ARC-03-1884-%20Adara%20-%20Recommended%20Sun%20Shading%20of%20a%20Western%20Elevation%20in%20Akure.docx