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a chandelier should be hung approx 30″ above the dining table
so, take the height of the room, 8′ in this case, minus the height of the table (typically 30″), minus the height of the fixture (28″ in this case) to determine if you have room to leave 30″ above the table, and have a little extra for canopy and chain. we have 38″ left. perfect. 30″ above the table, and 8″ of chain.
to determine if you have the right diameter for your room, take the width of the room in feet + the length of the room in feet. in this case we have approximately 12′ x 14′ = 26. so the ideal diameter for the light fixture for a room of this size is 26″. good stuff.