Such pyramidal canopies on terraces of sink directions is the ideal form ,that absorbs all the negative sinking streams.Since the pyramidal form has multiple virtues of complementary planets and elements ;it acts magically.As it has four sides and is based on square or rectangle it represents Earth-Element.As it is formed by four symmetric triangles ,it represent a balanced fire which is promotive of divine earth element.As it dehydrate the content it represent a controlled subtle form of fire element.As it makes pieces of the matter in its aura ,it has qualities of planet Ketu.As it contracts and shrinks the entity in its aura ,it has virtues of Saturn.As it holds the matter firmly its clutches are like the planet Rahu.Active fire symbolizes the characters of planet Mars.So terraces of Southeast-South-Southwest-west zones can be effectively treated by such pyramidal canopies.