Sunroom, solarium, patio cover, porch enclosure, garden room, country room, three-season room, all-season room, conservatory. These are among the many names given to the glassed-in additions that have become popular remodeling accessories. Typically, these structures are discrete units consisting of aluminum extrusions with insulated glass and foam panel infill.

But even among prefab units, there is a wide range of types and quality. According to Steve Pickens of Champion Windows, which sells and installs patio rooms through 55 showrooms nationwide, the terms "patio room" and "sunroom" are often used interchangeably by his staff to refer to a room surrounded in glass, creating a category that's distinct from a screened porch. In other companies, a sunroom has glazed roofing, while a patio room does not, and a room completely surrounded by glass may be called a "conservatory."

Code Category

Call it what you like, says Mike Fischer, technical director of the National Sunroom Association based in Topeka, Kan., but to a code official, it's either a patio cover or an addition. "Everything else is just a marketing term."

Appendix H of the International Residential Code defines "patio cover" as a one-story structure under 12 feet in height with at least 65% of the longest free-standing wall open or glazed. Such a structure can be built on a slab without footings and only needs to withstand snow loads of 10 pounds per square foot, but it also can't be considered habitable space. That means any openings between the patio cover and the main house must have exterior doors and windows that meet energy requirements. Anything else, explains Fischer, will require heating, and must have footings below frost depth and a structure suitable to carry the same structural design loads as the main house. "In most cases, the biggest issue is meeting the energy code," Fischer maintains. "If the roof meets the insulation requirement, it's usually strong enough to meet the snow load requirement." Another code concern, Fischer says, is egress. It cannot cover a bedroom window or door that serves as an emergency fire exit.

An all-season patio room must meet the same structural and energy code requirements as any addition.
Courtesy Creative Sunroom Designs An all-season patio room must meet the same structural and energy code requirements as any addition.

An all-season patio room must meet the same structural and energy code requirements as any addition.Courtesy Creative Sunroom Designs Fischer recommends pulling permits well in advance of a scheduled project. In some jurisdictions, particularly where high-wind and seismic codes apply, an engineer's wet stamp may be needed to certify that a system meets local requirements.

"Our all-season patio rooms require the same permitting and inspections as any stick-framed addition," says Celina Clark, vice president of Creative Sunroom Designs in Sullivan, Ill. "The concern here is meeting the energy code." Most customers, Clark explains, want to open the attaching wall, which means the glazing and wall panels must meet the same thermal performance requirements as exterior walls and windows.

Educating the Everyman

The trick, Clark says, is educating the buyer about the differences. "There's tremendous confusion," she continues, "Prices can range from $15,000 for a simple, three-season enclosure up to about $83,000 for a large, customized all-season room. Then there's everything in between."

A three-season room, which the IRC calls a "patio cover," is exempt from many requirements, but the attaching wall cannot be open to the home's living space.
Courtesy Creative Sunroom Designs A three-season room, which the IRC calls a "patio cover," is exempt from many requirements, but the attaching wall cannot be open to the home's living space.

A three-season room, which the IRC calls a "patio cover," is exempt from many requirements, but the attaching wall cannot be open to the home's living space.Courtesy Creative Sunroom Designs Part of the confusion stems from sunroom kits sold over the Internet or from home centers, which have created an impression that a sunroom is simply an accessory that can be hung from the side of a house. The actual performance of many of these kits, contends Clark, will be a disappointment.

Pickens agrees. DIY kits are designed to appeal solely on price, he contends, but they are no comparison to professionally installed rooms. The kits may look like top-of-the-line systems, using foam panels and thermally-broken aluminum extrusions, but DIY kits won't match the quality of a professionally installed system, he asserts.

"Kits are cookie-cutter products that do not necessarily blend into a home's architecture," Pickens adds. "Even if the manufacturer has great engineering and design, the fit of the components and weather tightness are not as finely tuned as the professionally constructed room. When one considers service and warranty issues, the homeowner usually gets a superior product and spends less with a custom-designed unit."