In warm weather a homeowner's thoughts turn to leisure hours outdoors and sprucing up poolside, patio, backyard or terrace.

Many will be replacing outdoor furniture or buying it for the first time, and may be surprised at the many styles and materials now available. The last few years have seen much change and improvement, along with a more intense and competitive market.

Holger Fack, furniture buyer for Chicago's Carson Pirie & Scott Co., says, "We've noticed a large increase in sales of summer furniture, possibly due to the high price of gas. A lot of people are staying home, not going on vacation. Many are upgrading their homes, and they're buying larger, more expensive, better-built summer furniture.

"We feel the direction is Brown Jordan lightweight aluminum furniture with vinyl strapping."

Another trend, Fack noted, is that people aren't just buying a couple of chairs, an umbrella and a table. "They buy the umbrella, the glass-topped table and accessory pieces such as lounge chairs, ottomans, chaises, bars, coffee and end tables. It's like having a rec room in your back yard."

He adds, "More important, they are beginning to buy deep-seating groups, similar to a living room furniture but made to be left outdoors. Winston Furniture has an aluminum deep-seating group in Textilene, a treated mesh that won't fade in the sun. Some of the aluminum frames being built today are guaranteed for 25 years."

Most manufacturers are using Textilene, a care-free, open-weave, vinyl-coated polyster fabric that can be left out in rain showers, but are giving it their own trade name. Some treat it as a generic name, such as nylon, and don't capitalize it, while others still do. Aluminum is a big seller, say dealers, because it's lightweight, doesn't rust, is attractive, is available in many colors and won't fade in the sun.

Aluminum with vinyl strapping is comfortable without cushions, lasts years and years, and comes in many styles -- from what you see at a public pool to the top-of-the-line stuff, according to Rick Williams, manager of Williams Patio Furniture. Tropitone is another popular manufacturer of this type of summer furniture.

The news in umbrellas is light, vinyl-coated mesh fabrics (Textilene) in dozens of colors and combinations that simplify the matching with chair seating. Breezes blow through this mesh without becoming trapped or lifting umbrellas away. The mesh also lasts longer than canvas.

Williams says the use of Textilene in seating cushions means they can be left out in a shower. "They dry out by the time the grass is dry. The cushions are of spun Dacron in heat-sealed envelopes inside the Textilene covers, remain odorless and do not deteriorate when left outdoors."

He adds, "There are also new finishes, including a polyester powder finish that is five to six times thicker than baked enamel and more chip-resistant." It is put on the frame electrostatically.