Do you only want the area rug to be placed under the coffee table as an accent? If so, measure your coffee table and add enough to the length and width for it to be to scale within the furniture grouping.
Do you want all of your furniture to be on the rug? If so, measure the perimeter of your furniture grouping and add six to twelve inches past each grouping, depending on the size of your room.
Dining Rooms: Measure the length and width of your dining table and add 4 feet overall to allow enough space for chairs to be easily pulled in and out. Most dining room tables require a rug that is at least 8 feet wide.
Bedrooms: There are a couple of options for placing area rugs in your bedroom. You can either use a large size area rug or several smaller size rugs around the bed. Depending on which option you choose, the rug size should be large enough for you to take a step or two when getting out of bed.
Entryways & Hallways: Consider purchasing a rug that can handle the high traffic that will occur in these areas. Popular rug choices for entryways and hallways are smaller size scatter rugs and runners. You can also add visual interest with different rug shapes like a round rug in these areas.
Living & Family Rooms: There a couple of questions to consider when measuring your living or family room for an area rug because furniture can centered on the rug or positioned off of the rug depending the size of the room and the look that you are trying to create.
Kitchens & Bathrooms: Most people prefer to place smaller size scatter rugs, accent rugs or runners in kitchens and bathrooms due to the size and function of this space in the home. Kitchens and bathrooms can handle more than one rug in smaller sizes depending on where the rugs will be placed. Scatter rugs are available in a variety of smaller sizes.