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First, let's talk quality. The best, and most expensive area rugs are the hand knotted Persian rugs. These are the longest lasting and the most beautiful. The more knots per square inch determines the quality of the rug. These measure from 40 to 1200 knots per inch.
The next best type of area rug is the hand tufted, these are 1/2 man made 1/2 machine made rugs that are more affordably priced but have similar characteristics to the knotted option.
An entirely machine made rug is also available and logically is the least pricey of the the 3.
Telling the difference, especially between the knotted and tufted is simply done by taking a look at the back of the rug. If you see the pattern in reverse, it's hand knotted, if you see backing, it's hand tufted.
Look for the "Rug Mark" label on all rugs you are considering to be sure there has been no child labor involved in the manufacturing of the rug.
Next, let's talk about material. If you and and your family are hard on rugs with heavy traffic, food spills and pet evidence...go with the synthetic stain and water resistant rugs at lower price points.
Cotton is also available, slightly more comfortable but will absorb and hold stains making them harder to clean. Place this type of carpet in a more formal room with restricted access.
There are also tough and tender "green" rugs made of plant based fibers such as jute and bamboo. Beautiful, biodegradable and renewable make this type of area rug a fantastic choice. The only disadvantage is that they will wear out much quicker than their synthetic or cotton counterparts.
Wool rugs are best used in rooms where traffic is limited to formal occasions and special events where food and drink are supervised.
The size of the rug is also an important consideration. Too large and it becomes a wall to wall carpet, which defeats it's purpose of defining space. Too small and it will set the room's balance off making the room less than inviting.
Proper design guidelines include: In the bedroom allow for 3' of rug on either side of the bed. Try to fit the nightstands on the rug as well. In the dining room the rug should accommodate a chair that has been comfortably pushed back from the table, than add an additional 6".
The living room is a little bit trickier and really depends on the look you are trying to achieve. The more causal look places the furniture 1/2 on 1/2 the rug. Placing the entire piece on the rug is the more formal position. Be sure not to out price the room with a rug that is more expensive than the furniture it is supporting.
Finally, to preserve the rugs look, comfort and stability place a rug pad underneath. The thicker the pad the greater the cushioning properties of the rug. Buy one that is 2" to 3" smaller than the rug itself. This will prevent slippage as well.
