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The Case for Instant Additions

Prefabricated sunspaces do more than let the sun shine in. They also add living space in less time than it takes to build a traditional addition.

Photo by Smith-Baer

No matter how large a house appears when you move in, it seems to shrink the longer you live there. If yours is starting to cramp your style, preengineered sunspaces could be a brighter alternative to building a walled-in, frame-construction room from scratch.

Also known as conservatories, greenhouses, and solariums, these panoramic living areas are made of aluminum or wood frames that hold large glass panels. Besides providing a light-filled living area, prefabricated sunspaces give the feeling of being outdoors while you relax inside. They go up faster and easier than frame-built rooms, and can also help with heating costs. And while prices for these instant additions can top $30,000, a 10x7-foot basic model starts at just $6,000.

There are a few important details to consider when buying a sunspace and having it installed. What's more, in a few scenarios they aren't such a bright idea.

Photo by Smith-Baer

Pros and Cons

Most sunspaces arrive on site as kits a contractor can install in a few days instead of the weeks it takes for a site-built addition. Although they're prefabricated, variety isn't a problem. Choices include everything from rooms that recall 19th-century English conservatories to contemporary designs. All offer the latest energy-efficient glass which, when combined with the right location, can reduce energy bills by up to 30 percent.

There is a darker side to sunspaces. For one, all that glass compromises privacy. If your addition will be in full view of either neighbors or passersby, wood-frame or masonry construction is a better choice. What's more, despite the many styles available, sunspaces simply won't blend with certain types of architecture. And though special trim, shading options, and other extras are available, site-built additions offer more opportunities to customize. Finally, don't let the words "prefabricated" and "kit" lull you into thinking anyone can assemble a sunspace. Most should be installed only by a professional contractor.

If you want privacy, a sunspace is not your best choice. But placed in a secluded location, a sunspace, such as this curved glass model from Lindal Cedar Homes, is a great way to add living space while enjoying nature.

Where to Find It (page 6) lists a number of major sunspace manufacturers, which sell directly or work through local dealers, which you can find in the yellow pages under "Greenhouses & Solariums." You'll also find local companies listed in this section of the directory.

Installation cost is one area where prefab and site-built additions come out about even. Both require a slab or pier foundation. Higher material costs for prefab sunspaces also offset their short labor schedule. "A large expanse of glass wall usually costs more than a frame wall with a window in it," explains Richard Bendix, vice president of Lindal Cedar Homes in Seattle.

That means even a $6,000 entry-price sunspace will cost more like $8,500 to $9,000 with delivery charges, foundation work, and installation. On the other hand, customizing a site-built addition can drive costs up far beyond those figures.

<p>Although sun-spaces are produced as kits, they can be adapted to most sites. To line up with the existing kitchen, the floor of this sunroom is raised about 5 ft. off the ground. This unit also requires a low wall around the perimeter of the structure.</p>

Although sun-spaces are produced as kits, they can be adapted to most sites. To line up with the existing kitchen, the floor of this sunroom is raised about 5 ft. off the ground. This unit also requires a low wall around the perimeter of the structure.

Photo by Geoffrey Gross

Energy and Comfort

Because all that glass acts like a giant solar collector when the sun is shining and as an escape route for heat when it isn't, both the sunspace and adjoining rooms can become unbearably hot or too cold to be in without a jacket or coat. Minimizing these uncomfortable temperature swings depends on which direction the structure faces, its design, and the materials used.

Picking your site. Sunspaces work best facing south, where they'll get direct sunlight. Sunrooms on the north side of a house get no direct sunlight during winter, while those facing due west become overheated by the late afternoon sun. Unfortunately, many houses don't have direct southern exposure; still others won't allow a due-south location for the new room. Southeast or even slightly southwest will work in either case.

Locating a sunspace to take advantage of the sun is important, but don't forget it can also provide incredible views and a feeling of the outdoors. Try to find a spot for your sunspace that takes advantage of both. This room from Lindal Cedar Homes features tinted overhead glass and blinds on the vertical glazing to keep out unwanted sun.

Making the connection. How a sunspace connects to the rest of the house directly affects its energy performance. For example, if you live in a cold climate and want extra living space without the additional heating costs, separate the sunspace with a wall that includes a door and a fan. The fan pulls heat from the sunspace into the house during the day while the door seals off the area when it cools down at night. But because the temperature inside sunspaces heated only by the sun can fluctuate by 40°F in 24 hours, the space you gain is part-time only.

If you want to add comfortable full-time living space, there are some other options. A popular one is to use the sunspace to enlarge another room — often a kitchen or family room. The sunspace still collects heat during the day. But because it's connected to the rest of the house, it requires backup heating. Baseboard heaters or radiant floor heating are two possibilities.

Climate control. The more time you'll spend in your sunspace, the more important it is to control heat loss and overheating. Your biggest weapon is the glass itself. Most manufacturers offer several kinds you can match to your climate. Four Seasons Sunrooms, based in Holbrook, New York, sells 16 kinds of glass, from clear double-pane units to triple-glazed low-e glass. (See Window Glazing for more details.)

In cold-weather climates, choose glass that keeps heat from escaping to the outside. In warm-weather ones, look for glazing that prevents heat buildup—a more common problem than heat loss. Adding shades or blinds to overhead glass can help prevent overheating; most manufacturers sell them as options. If you don't want to invest in shades right away, be certain the design you choose has tracks that make retrofitting easy.

Another option is to eliminate overhead glass altogether. Most manufacturers offer sunspaces with solid roofs—a feature that eliminates much of the heat buildup. Patio Enclosures, based in Macedonia, Ohio, lets customers specify solid-roof sunrooms and then place 3x3-foot glass panels where they want them. The result is both protection against overheating and natural light where needed.

Flooring material also affects how hot the space gets. Adding thermal mass, usually with a masonry material, such as ceramic tile over a concrete slab, absorbs some of the heat from the sun; it releases the heat during cooler evening hours. The Passive Solar Industries Council, a group of manufacturers and building professionals in Washington, D.C., suggests an average of 3 square feet of 4-inch-thick solar mass for every square foot of clear double-glazed glass area. Even then, the temperature within the space can vary as much as 30°F on a clear winter day. And using that much masonry can be a challenge in a typical kitchen expansion, especially because at least 75 percent needs to be exposed to sunlight to be effective.

Most sunspaces require a combination of temperature controls. Discuss these issues with your dealer. And check with a heating and cooling contractor on how the sunspace will affect energy use and comfort in the rest of your home.

<p>The key to a successful installation is precision so precut parts fit together well. Here, the contractor attaches a metal "shoe" to the base of one of the wood beams. This piece will connect the beam to the aluminum sill along the long wall of the sunspace.</p>

The key to a successful installation is precision so precut parts fit together well. Here, the contractor attaches a metal "shoe" to the base of one of the wood beams. This piece will connect the beam to the aluminum sill along the long wall of the sunspace.

Photo by Geoffrey Gross

Getting It Built

Along with a foundation, sunspaces require assembling and sealing large expanses of glass and making a watertight connection to the house itself. Fortunately, most dealers work with teams of local contractors to assemble their products. Expect labor and installation charges to start at $2,500 for a 10x7-foot sunspace.

If you hire your own help, look for experience with the sunroom you're buying. The requirements vary from one manufacturer to the next. Even different lines from the same manufacturer can require different building procedures.

You'll also need the usual building permits and variances. Inspectors tend to approve the structure if it's from a well-known manufacturer. But most inspectors will scrutinize any site-built work, including the foundation.

A sunspace can make a truly radiant addition to your home. Just be sure the design meets your needs and the materials you choose fit your climate and lifestyle.

<p>Once the sill is attached to the wall and a ledger is screwed to the house, the beams are screwed in position. This unit has seven beams in all, creating six bays for overhead glazing.</p>

Once the sill is attached to the wall and a ledger is screwed to the house, the beams are screwed in position. This unit has seven beams in all, creating six bays for overhead glazing.

Photo by Geoffrey Gross

Some Assembly Required

Sunspaces can be used to create separate rooms or to expand kitchens or family rooms. The Four Seasons sunroom shown here, being assembled by Elmsford, New York?based Suburban Sunrooms, is being used to add about 160 square feet of sun-filled space to the small kitchen in a suburban ranch-style home. The area is at the back of the house and was built over an existing flagstone patio.

When we caught up with Chris and Tim from Suburban Sunrooms, the kitchen already had been gutted and the back wall of the house removed. Construction had proceeded up to the floor-framing stage with the stub wall shown in the photos in place. At that stage the crew began assembling the sunroom kit.

If a sunspace project is in your future, here are some tips we gleamed from dealers and contractors.

When hiring a sunspace contractor, make sure the one you settle on is familiar with the kit model and manufacturer you have chosen.

Your contractor should take an inventory of parts before construction on the sunspace begins. If something is missing, notify the company immediately to avoid schedule snags once the crew is on site.

The connection between the house and sunspace is critical. Ask the contractor to detail the flashing used and then inspect it thoroughly at the end of the job.

<p>The last step of construction is installing the precut glazing units. Aluminum tracks attached to the wood beams hold the glazing in place.</p>

The last step of construction is installing the precut glazing units. Aluminum tracks attached to the wood beams hold the glazing in place.

Photo by Geoffrey Gross

Where To Find It:

Abundant Energy

Box 307

Pine Island, NY 10969

800-426-4859

American Conservatory Co.

1380 Wayne Ave.

Indiana, PA 15701

888-822-2485

www.americanconservatory.com

Florian Greenhouse

64 Airport Road

West Milford, NJ 07480

800-FLORIAN

www.florian-greenhouse.com

Four Seasons Sunrooms

5005 Veterans Memorial Hwy.

Holbrook, NY 11741

800-368-7732

www.four-seasons-sunrooms.com

Hartford Conservatories,

Inc.

96A Commerce Way

Woburn, MA 01801

800-963-8700

www.hartford-con.com

Lindal Cedar Homes

4300 S. 104th Pl.

Seattle, WA 98124

800-426-0536

Omega Sunspaces

3852 Hawkins NE

Albuquerque, NM 87109

800/753-3034

Patio Enclosures, Inc.

720 E. Highland Rd.

Macedonia, OH 44056

216-468-0700

Suburban Sunrooms

Sunspaces assembled by this

Four Seasons dealer are featured in this article.

83 E. Main St.

Elmsford, NY 10523

914-592-7455

Sunshine Rooms

3333 N. Mead

Wichita, KS 67219

800-222-1598

US Sky

2907 Agua Fria

Santa Fe, NM 87501

800-323-5017

Sun PorchStructures, Inc.

495 Post Rd. E

Westport CT 06880

800-221-2550

www.sunporch.com

The following publications provide information on the energy aspects of site-built sunspaces, but the information is applicable to prefabricated units as well. Though now out of print, you can find these three in used-book stores or libraries.

The Passive Solar Energy Book

by E. Mazria, Rodale Press, 1979.

This is a great general reference on passive solar energy.

The Sunspace Primer: A Guide to Passive Solar Heating

by R.W. Jones and R.D. McFarland, Van Nostrand Reinhold Company, 1984.

Sunspaces: New Vistas for Living and Growing

by P. Clegg and D. Watkins, Garden Way Publishing, Storey Communications, 1987.

For information on passive solar energy, contact:

The Passive Solar Industries Council

1511 K St. NW, Suite 600

Washington, DC 20005

202-628-7400.