More than a multipurpose deck, an outdoor room is typically designed and outfitted for a specific function, whether it's lounging on an all-weather sofa in an open-air den or cooking in an alfresco kitchen packed with rust-resistant stainless-steel appliances. And though the room can be located almost anywhere—as an extension of your house or a separate, secluded retreat in a quiet corner of your property—there are some general guidelines for creating one.
Typically, an outdoor room requires some sort of floor to establish the footprint. (Pea gravel, paving stones, or steppable ground cover will do.) You'll also need walls: A border of potted plants or a stacked-stone sitting wall can create a feeling of enclosure. And you'll want a roof, which can be as refined as a beadboard porch ceiling or as rustic as a natural arboreal canopy.