Kathy Marks-Petetit can't begin to express the importance of having a meal outdoors.

"It's a matter of escape," says the owner of the Park Avenue Mansion, a bed and breakfast in St. Louis. So she and her husband, Mike, created outdoor living, dining and entertainment spaces so that their guests feel as if their rooms extend outdoors.

Just as barbecue grills evolved into mini-kitchens with refrigeration and cabinetry, fashionable seating arrangements, lighting and decorative items are helping living and dining rooms migrate to the patio.

The Petetits' outdoor rooms are tied together with orange and green floral cushions, which soften the metal patio furnishings.

"Kathy designed it so that each patio has a different feeling," Mike Petetit says.

Couples can relax inside the gazebo, which has a ceiling fan for warm nights. Or friends can sit on barstools in "the wine room" and socialize with cheese and a Cabernet.

Mimicking the feel and flow of the first floor of their home, the series of patios creates outdoor parlors and dining spaces separated by the garden. And each room has a water feature that makes it practically soundproof.

"It is important to have privacy," Marks-Petetit says. "When you're in these rooms, you can't hear the other people, so if you want to be romantic, you can."

Rope lighting rings the fence, and a chandelier hangs from a pergola. The lighting gives enough glow for guests to read a book or have a nightcap at the bar underneath the deck.

It's beautiful, cozy — and elaborate. Yet, the Petetits' rooms illustrate the possibility of extending a home's square footage into the backyard.

"What people are looking for is a way to enlarge their homes," says Mark Chapman, the senior designer for Expo Design Centers. "And that's why you're seeing so many great rooms being created for outdoors."

Chapman specializes in outdoor living and says consumers "want real rooms with defined space that they can decorate and personalize."

Gazebos — which are becoming more posh, with pitched roofs and shelving — can provide a focal point of shelter and shade.

"I like to call them garden houses," Chapman says of the tent-like structures showing up on decks, in yards and next to pools. They help give "a more casual extension of indoor space."

Good outdoor living, Chapman says, "all starts with the furniture."

"There are so many choices that you can really build upon whatever your style is indoors," he says.

Patio furniture design is much more serious, stylish and functional these days, so a design direction can be carried through without the worry of weather. For instance, Expo's wicker Harbor Breeze patio collection has pretty jewel-toned cushions. But built inside is a drainage system that allows pillows to dry quickly after a summer rain.

"Wicker used to be something that looked great but wouldn't last very long," Chapman says. "Now, manufacturers are making faux wicker, which is really aluminum, and it can withstand the elements."

That kind of practicality is essential as consumers want indoor-style luxury, outside. If you are accustomed to having a fire burning during cool weather dinners, you probably want that experience outdoors.

Susan Kearney agrees. She moves all of her dinner parties to the deck when the weather turns warm. "We like to bring out tablecloths and serve most of our meals outdoors," she said. On chilly nights, the Kearneys will warm up by their fireplace.

"We use our outdoor space every day," she says.

Manufacturers recognize that people are spending so much time outdoors that attention must be paid to decor.

"It's a blurring of the lines between inside and out," says Joshua Thomas, a spokesman for Target. Firebowls, synthetic Persian and kilim rugs, artwork, decorative accents and weather-friendly lighting are just a few of the choices that bridge the interior and exterior.

"This season, lighting is fabulous," he says. "There is something for every personal style." Glass housings that fit over electrical components make it possible to trade torches for torchieres or mix wall sconces with paper lanterns. That adds an elegance to a patio that can typically be found only — well — indoors.

Thomas also thinks that outdoor living is an opportunity to take design risks.

"You could uses ottomans instead of chairs," he says. And if your interior is very formal, you can try something much more modern outside."

He says "a chaise with an unexpected print with minimalist decor will give you a chance to try something you wouldn't do inside, as well as can surprise your guests."