The cost to screen in a porch depends on whether you are adding screens to an existing structure or building a new one from scratch. Adding screens to an existing porch costs about $5 to $7 per square foot, with a national average cost of around $2,800. For example, screening a 12-by-12-foot (144-square-foot) porch would likely cost between $700 and $1,000. If you are building a new screened-in porch, the cost is substantially higher. A new 12-by-12-foot screened-in porch can cost between $6,400 and $18,300, while a new 14-by-16-foot one averages around $11,000. The final price will vary based on the size of the porch, labor costs, and the materials you choose.

The least expensive way to enclose a porch is with screens. These protect the room by preventing insects from entering and, if you live in a warm climate, provide excellent airflow during hot summer months. Screens cost far less than any other alternative, so if you are against getting permits, spending too much, or enclosing your porch in walls or glass, screens are the best choice. 

Whether it's better to add a sunroom or a regular room to your home depends on your goals. If you need extra bedrooms, building rooms with four standard walls makes more sense than adding a sunroom. If you don't need extra sleeping areas but would like to expand the living space of your home, a sunroom makes sense.

A Florida room doesn’t have insulation, nor is the space heated, so in most cases, the room won’t be comfortable enough to use during the winter months. A four-season room, which is like a Florida room that’s insulated, heated, and cooled, is a better option if you’re looking to enjoy your sunroom all year long.