Size and Shape
The size of the rug is dependant on the shape of the rug, and the shape should always mimic the space it occupies. A rectangular space requires a rectangular or oval rug; a square space requires a square or round rug. The oval and round rugs suggest a more formal decor; the rectangular and square rugs are usually found in less formal rooms. Rug sizes are listed as width by length and written as 8 x 10, for example, which would be a rectangular rug 8 feet wide and 10 feet long.
Cover the Floor
If the majority of the floor is to be covered, 8 to 16 inches of hardwood should be left exposed around the perimeter of the rug. This size suggests a very formal room. If the edges of the rug lay in the traffic flow path, increase or decrease the size of the rug as necessary. Doors in this room should open out, and the locations of radiators and heat registers need to be considered.
The rug under the dining room table must be large enough so all the legs of the chairs, when pulled away from the table if a person stands, remain on the rug, which is best accomplished when the shape of the table mimics the shape of the rug. Sideboards and service furniture should remain off the area rug and at least 18 inches from the rug to the wall are required for people to pass behind the table.
A conversation area in a large living room is defined by the furniture grouping, which is anchored by the area rug. If the grouping is a square, the rug should be square; if the grouping is rectangular, the rug should be rectangular. The rug should extend under all furniture at least 6 inches with all the front legs of the furniture standing on the rug. A more formal mood would have the rug extending to the back legs of the major pieces of furniture with all the legs of the occasional or side chairs standing on the rug.