More than a space to raise plants, these glass-enclosed rooms are also a popular place for home owners to entertain and relax.

Regardless of the season, home owners who are lucky enough to have a conservatory often consider this room the most beautiful spot in the house.

It's a sunny space to read a book and catch a spring breeze, a fun place for children to watch the snow fall, or a retreat where adults can unwind and listen to the rain fall on the gloomiest days of the year.

There's a natural tendency to gravitate to the room in the winter or the summer, James Licata, owner of Town & Country Conservatories in Chicago. You feel like you're outdoors even though you're not.

Licata's own conservatory, attached to his post-Victorian home, serves as a spillover area from the nearby kitchen.

Like Licata, many home owners today use their conservatories as a living space, breakfast room, or family room. Some even use them to enclose a swimming pool if the space is large enough. However, there was a time when these spaces really were meant for plants.

Once Were Called 'Orangeries'

When conservatories became a popular home feature during the 19th century, they resembled greenhouses because and were used to propagate precious plants - especially orange trees brought by English tourists from Italy. That's why these early conservatories were also commonly called orangeries.

As time went on, conservatories evolved into the grandiose spaces that people often associate with the word today. The Crystal Palace, built for the 1851 Great Exhibition in London, was probably the most well-known conservatory of its day. The 90-acre building was constructed by 3,000 men and remained the ultimate glass edifice until it burned down in 1936.

Conservatories remained generally popular as a home feature until World War I, when home owners caught on to the structure's major drawback: Made with single-glass panes, they cost a small fortune to warm because they didn't retain heat very well during winter.

Resurgence in the 1960s

These glass houses didn't become popular again until the mid-60s when technology of construction materials advanced enough to make the rooms more energy efficient. Builders help home owners cut down on heat loss by using two to three glass panes sandwiched together instead of single glass panes.

This innovation led the English to once again to construct their own personal Crystal Palaces. While conservatories are still more popular in the U.K., American home owners are adding them onto their residences as a way to bring more light and glass into new homes.

A Unique Home Feature

If your listing has a conservatory, don't pass up the opportunity to market the room in your listing materials. These rooms differentiate the home from others on the market and appeal to buyers who love plants, natural light, and good views of the outdoors - and who doesn't? Artists particularly like these spaces because the lighting is conducive to painting and sketching. But most of all, the rooms extend the home visually by drawing in the surrounding landscape.

Conservatories bring in the outdoors, says Andrew P. Roberts, Operations Director for Blue Diamond Conservatories, in Fombell, Penn. Roberts has a Malibu, Calif. client who's building a conservatory that will serve dual purpose as a work space and an area for growing orchids.

Practical Knowledge

Whether working with buyers or sellers, here are some everyday facts you should know when talking to clients about conservatories:

  • -  It's not a greenhouse. While they may look alike, green houses and conservatories are different, according to Licata. Greenhouses generally have dirt floors and are filled with plants and potting sheds. Conservatories can also contain many shrubs and flowers, but most have finished floors and areused a living space.
  • -  They tend to be pricey add-ons. Conservatories are slightly more expensive than your average addition because the roof is constructed just like the walls.
  • -  Pre-fab is an option. You can cut construction costs by 20 percent by using prefabricated modular units. However, most conservatories in the U.S. tend to be custom-designed because that's the only way owners can fit one onto their home. Custom conservatories usually look they are a natural extension of the house.
  • -  There are many styles. Styles range from Victorian, Edwardian, and Georgian to simple lean-tos and modern geodesic domes. Larger ones with windows that keep UV rays at bay are ideal for lap or swimming pools.
  • -  Heating/cooling is still an issue. You lose more heat through the roof during the winter, but on a sunny day there's a heat gain, says Licata. It's a close call. It's also more expensive to cool a conservatory during hot summer days. Those expenses can be offset by installing roof shades, which reduce heat generated by the sun without diminishing sunlight.
  • -  Tough to keep squeaky clean. They will also cost more to keep clean, although that can reduced by installing glass that's easier to scrub. Aluminum caps will virtually eliminate any painting. You simply wipe it down to return it to its original appearance.