When your children are teenagers, your family room might finally look the way you imagined when you decided to buy a new house. But if they're very young when you move in, you will be happier if you start out on the spare side and let the family room "grow" with your children, said Skip Sroka, a Bethesda interior designer who is one of nine children himself.

When kids are small, they need space to crawl, play and run around, Sroka said. If you put a lot of furniture in the family room, it will just be in the way. A sofa, a side table and possibly an armchair will be plenty, especially because only the adults will use them. Young children will spend most of their time on the floor.

Because you will be down there at least half the time as well, you will want flooring that you can sit on comfortably. Your best option for comfort and cost is wall-to-wall carpet with a good pad. No matter where your children take a fall, they will have some cushioning.

To keep your sanity, your carpet must be easily cleaned and in a color that will hide the dog accidents, vomit, spilled juices, dirt and all the other abuses that will be inflicted on it during those early years of child rearing, said Deborah Wiener, an interior designer in Silver Spring and the mother of two boys.

A wool carpet will do nicely, but wool is pricey and some children are allergic to it. For durability, Wiener recommends a synthetic material such as polyester, olefin or nylon treated with Dupont's Stainmaster. Darker colors such as chocolate brown, medium to dark blue or a dark taupe will hide stains, but they can make the room look more somber than you might want. Wiener suggested a bright but inexpensive throw rug. The rug should also be cleanable, but if something awful happens, you can throw it away and get another one.

Comfort in a family room also means adequate lighting, natural and artificial, Wiener said. All the windows that make the family room in the builder's model bright and sunny are not necessarily included in the base-price house, but they definitely enhance the space. On cloudy days and in the evening you also need illumination. Wiener suggested recessed light fixtures to avoid lamps with cords that will get tripped over and pulled out of the wall.

If you plan to have furniture in that "floats" in the middle of the room, not against the wall, you should have outlets installed in the floor during construction. Otherwise, when you eventually put in side tables and reading lamps, the cords will stretch halfway across the floor to a wall outlet. Figure out about where your furniture will go, put in the outlets and childproof them until they are needed.

You will need some kind of window treatments, and both Sroka and Weiner recommended honeycomb shades, such as Hunter Douglas Duette. When they are pulled down during the day, the light that comes through is wonderfully soft and diffuse, and the shade can be opened from the bottom up or the top down. The latter position provides both sunlight and privacy, which can be an issue if your neighbor's house is only 10 feet away, as it is in many new subdivisions. Many manufacturers offer such shades. Whatever you select, make sure it has safety features so that a small child can't get a cord wrapped around his or her neck or swallow plastic parts.

Practicality and initial spareness in the family room do not mean you have to look 100 percent plain, both designers said. Hang artwork and splurge in good conscience on a sturdily built sofa that looks great while withstanding the rigors of child-rearing.