Lynn Heintz and her family had a tough decision to make.

They had to pick a carpet that would cover most of their 2,200-square-foot house. After some compromising, they narrowed down their choices to three different shades of beige.

In the end, they settled on the lightest-color carpet: “to lighten up the room,” says Heintz, 47, of Fresno, Calif.

For Heintz, her husband and their 17-year-old daughter, this was their first journey into carpet world. They only knew what they wanted: a durable carpet that wouldn’t easily show dirt or wear.

Like many who are buying new wall-to-wall carpet, “we started off knowing absolutely nothing about it,” says Heintz, who was replacing 23-year-old carpets. “We learned as we went along.”

In case you’re looking for a new carpet, here’s a primer to get you started:

Residential carpet is commonly made from three synthetic fibers: nylon, polyester and olefin, which is polypropylene.

Nylon is wear-resistant, durable and ideal for all traffic areas. Typically, nylon carpets cost the most of the three. Polyester is easily cleaned, takes a lot of traffic and resists water-soluble stains. It works well in children’s rooms.

Olefin is easily cleaned, resists wear and permanent stains and withstands plenty of foot traffic. “It’s designed more for commercial use,” says Vince Antonino, vice president of Adanalian Design Floors in Fresno.

Two other fibers are wool and acrylic. While soft and luxurious, wool is expensive. Acrylic is commonly used in bath and area rugs.

Carpet comes in several styles:

• Loop pile: The yarns are looped. They can be level or have different loop heights, creating a pattern and texture.
• Cut pile: The yarns are looped, then cut. There are three types of cut pile — plush, Saxony and frieze. Plush has a smooth, level surface and a formal look. Saxony also is smooth and level, but the yarns have a slight twist that makes the ends more visible. This type looks less formal.
• Cut and loop pile: A mix of cut and loop yarns creates a variety of textures.

From dark blue hues to neutral, plain beiges, carpet comes in many colors. Customers can have carpets with colorful floral prints or simple two-color dot patterns. They can pick a berber carpet, which has random flecks of color and typically has loop-pile yarns, or go with a single-color plush.

Underneath every wall-to-wall carpet is a pad or cushion, which forms a good foundation for the carpet, adds insulation and reduces noise. Pads can be made of fiber, rubber or various polyurethane foams, including a multicolored bonded foam product called rebond. Pads range from 3/8 inch to 7/16 inch in thickness.

The cost of carpets varies widely, from $3.50 a square yard for an inexpensive plush up to $75 to $85 a square yard for wool carpet.

Selecting the carpet

When people are out picking carpet, they need to ask themselves several things: How will the room be used? What kind of traffic will it have? How long do you plan to live there? Are there any pets or children?

According to a report by the Carpet and Rug Institute, a national trade association, shoppers should pay attention to the density, twist and performance of carpets.

Density refers to the amount of yarn in the carpet and the closeness of the tufts. Denser is better, especially for high-traffic areas. The twist of yarns should be neat, well-defined and tight. Yarns get their twist through a heat or steam process, which enables them to hold their twist over time. Many carpet manufactures also will give their carpets a performance rating — high, moderate or low — for various traffic areas.