Al Heavens is a Haddonfield, N.J.- based, nationally syndicated, home-improvement writer and author whose newspaper columns, magazine articles, and books have been the first word on remodeling for 50 million readers for more than three decades. He is the author of What No One Ever Tells You About Renovating Your Home and Remodeling on The Money: Fifteen Innovative Projects Designed to Add Value to Your Home and was “The Gadgeteer” on Discovery Channel’s Home Matters program.

When I was little, I lived on the first floor of the house my grandfather built.

My aunt and uncle lived on the second floor, which had a sunporch. My cousins and I would gather there year-round to play games and have sleepovers. On summer nights, with all the windows open and a fan going, we’d camp out.

My uncle called the sunporch a “Florida room.”

I didn’t know why until I start going to the Sunshine State on business trips in the 1990s.

The Florida room started out in the late 1950s as an enclosed porch. It was very popular for about 10 years as extra space where you could keep an old couch and a chair or two and relax.

There was a day bed in my uncle and aunt’s Florida room, and that’s where I would sleep after my parents and I moved, and I returned for visits. Even in the winter when a small space heater was used to provide warmth.

Very few builders in Florida offer Florida rooms these days. One reason is that the space once occupied by the Florida room is being used by the family room.

Another reason is that builders must be careful where they put windows because a western exposure in the state’s semi-tropical climate can take a toll on people and furniture.

I have friends in the Philadelphia suburbs who have a Florida room of sorts. Their Florida room is no mere enclosed porch. The room, which has six large windows, expands off the kitchen and increases living space by 180 square feet.

Instead of a place to throw old furniture, they use the room as a place to relax alone on the sofa, a bright, airy room where they gather for morning coffee on weekends. Its location near the kitchen gives Mom the chance to talk to her two children while they do their homework, and she prepares dinner.

Their Florida room is just one of several “special rooms” incorporated into new construction or carved from unused space in existing homes or additions.

These special rooms can be spaces off the living room that appear in numerous configurations or guises, or as `bump-outs’ in the standard floor plans.

Among these special places are conservatories that offer large, sunny, and luxurious spaces for entertaining. I once saw a two-story conservatory in Ballyvaughan. Ireland, that had two large and luxurious back-to-back secondary bedroom suites with sitting areas on the second level.

There also are sunrooms and solariums. Then there are greenhouses, which, can be a bump-out off the kitchen in the back of the house instead of a deck, or in addition to one.

Ideas are unlimited, especially if you have the money.

The conservatories usually are relegated to the front of the house, while solariums and sunrooms usually appear at the rear.

This placement is what is meant by “retreat and elite.” The elite rooms like the conservatory are part of the front elevation of these houses. They give the house curb appeal. The retreat rooms are places where the family can gather out of the public eye and cocoon, just like they have since the 1980s.

How does a conservatory differ from a sunroom, which is the better-known description of this kind of architectural feature?

The answer is snob appeal, the manufacturer of conservatories once told me. The word conservatory generally refers to a more traditional sunroom design. It conjures up an image of Europe, where sunrooms, conservatories and orangeries had functional values as well as aesthetic ones.

Conservatories are all glass, while orangeries are brick buildings with large glass windows and are designed to retain heat at night for growing of oranges. For that reason, they are warmer than conservatories.

Most conservatories these days are being added to existing homes rather new ones.

Whatever you call them, conservatories, solariums, and orangeries involve lots of glass, which is why they all qualify as sunrooms. The glass is used to control solar radiation — energy from the sun — by reducing or increasing the amount of heat that the sunlight brings into a room at a given time.

Modern sunrooms are most often described as solariums, patio enclosures and garden rooms. A solarium — the term is often used interchangeably with conservatory — typically has four glass walls and a glass ceiling. A garden room has three glass walls and a solid fourth wall.

Where the traditional conservatory and the modern sunroom are almost identical in function is in the garden room, which is both extra living area and home for plants.

When the living area is of primary importance, however, it is a garden room. When the plants predominate, it is a conservatory.

Thus, a conservatory is first and foremost an indoor botanical garden. When wealthy Frenchmen began constructing them in the 1700s, the chief purpose was protection for orange, lemon, and lime trees during the winter.

Then there are bonus rooms, which aren’t rooms at all but spaces that will become something when the homeowner needs them.

Bonus space is probably one of the most popular options in new construction, because it gives the buyer the option of having room to grow without having to decide what to build and pay up-front for it.

Bonus rooms can be anything and everything. In Texas, where houses typically have no basements and a second floor or loft area is often known as a Texas basement, the bonus space often accommodates a playroom.

The bonus space often becomes an in-law suite, or a room for a “boomerang” child — one who appears at the door when he or she is between apartments, schools, or careers. It is also used for storage, home offices, exercise rooms, or nothing at all.

The demand for special rooms has meant that traditional rooms have lost some of their appeal. For example, living rooms have gotten smaller over the years as family rooms have grown larger and more important.

However, the desire for formal space once provided by the living room has manifested itself in the conservatory, believe it or not.

Regions share a few preferences. One is house size. According to a survey by the National Association of Home Builders, buyers in all regions are looking for houses with more than 2,000 square feet of living space. They also prefer to pay no more than $200,000 for whatever they buy.

Good luck with that.