Traditional sofas or couches are designed for indoor use. Depending upon the manufacturer, they have a metal or hardwood frame.
Less durable frames are constructed from soft woods like spruce and pine. Often, upholstered couches are treated with a stain conditioner to safeguard against the buildup of spills, stains and dirt, but are not designed to hold up against outdoor elements.
Patio sofas made of cedar, teak or redwood will stand up to a range of weather conditions; redwood will also resist rot. The pieces can be stained to prevent fading, which occurs over time.
For the look of wood or wicker but material that stays cool to the touch, resin is the best option. It is 100-percent weather-resistant and is one a relatively inexpensive material.
Iron and Aluminum Sofas
Because of their weight, iron sofas are cumbersome to move, but are durable and can withstand years of use. To make iron sofas more comfortable, it is best to outfit it with an all-weather cushion to guard against heat.
Aluminum sofas are lightweight. They withstand all outdoor elements, and a quality sofa can last for over 30 years.