If you're making new pillows or replacing the stuffing for your outdoor furniture, you can choose among stuffing materials -- from inexpensive polyester fiberfill to specialty foam such as that used on boats. Cover your pillows with a durable, outdoor-rated fabric such as cotton duck, vinyl PVC. These fabrics come in many patterns and colors that complement your decor. No matter what fabric and stuffing you choose, extend the life of outdoor pillows by bringing them inside during wet weather.
Polyester fibers are available in a free-form, loose filling called fiberfill, or as compressed batting. Both forms are washable, non-allergenic and resistant to mold. Loose fiberfill is useful for stuffing round and other odd-shaped pillows. Polyester stuffing absorbs water, so the pillows must be dried if left out in the rain. Because polyester filling compresses with use, it's best used for accent pillows that you can replace every year or two.
Polyurethane foam is widely used for medium-firm cushions. Because it soaks up water, it must be treated to repel mold and mildew. You can also protect it with plastic sheeting beneath the cushion cover. Open-cell foam is durable and allows water to pass through with little absorption. When treated to resist mold, it is ideal for patio and boating cushions. Closed-cell foam is very firm and does not absorb water. Because it is rigid and buoyant, it is used in flotation devices and other specialty applications.