Building a sunroom is usually less expensive than the cost of building a home addition, but it depends on the type of sunroom. A four-season sunroom will cost more than a home addition because it’s basically a home addition with larger, more expensive windows. All other types of sunrooms will be more affordable than a home addition of an equivalent size because they don’t have insulation, heating, cooling, electrical connections, or plumbing.

Your maintenance needs revolve around the type of foundation you choose, as well as how you furnish or decorate it. Patios require little else other than the occasional hose-down, but decks and other wooden structures will require annual power washing and sealing. You may also need to restain the wood every two to three years.

Adding a solid roof rather than building a pergola or leaving the space open will make maintenance much easier. Without a roof, you will need to spend more time sweeping, washing, and covering your furniture to protect it from UV bleaching.

An Arizona room may or may not count toward your home’s square footage, depending on local regulations and the specifics of the room, but generally does not get included in the total square footage. In many locations, a room needs to be built to the same quality as the rest of the home, have an integrated heating/cooling system, and be habitable year-round to count toward square footage. 

A screened-in porch can add value to your home, with a potential return on investment (ROI) of 70% to 84%. The actual value added depends heavily on several factors. Climate is a major consideration; homes in warm, humid, or buggy areas (like the Southern regions) see the highest ROI. In colder climates, the value is diminished as the unconditioned space is unusable for much of the year. Other factors that influence the return include the quality of materials and construction, the size of the porch, and the local real estate market. While a screened-in porch can enhance curb appeal and attract potential buyers, it is not included in the home's total square footage for appraisal purposes.