Look at the walls of your house. What holds up those walls? Who says what can be used to hold up those walls? It's usually not the builder's choice. In almost every case, those decisions already have been made in the local building code.
The building code is a contractor's bible. Essentially, a building code is a thick set of rules, adopted as law by local governments, that tell contractors what they can and cannot do.
A building code '' . . . sets the minimums, but in effect, what it becomes is the standard,'' said Bill Hewes, Orange County building director.
Because building codes set certain minimum levels of performance, they have some impact on the prices that home buyers pay, although builders and code officials rarely agree on just how much costs are affected.
Virtually every facet of building a house is covered in the code, from the size of the lumber that can be used to the spacing between the studs to what kinds of materials are allowable for flooring. Plumbing, roofing, electrical wiring, heating and cooling systems are all covered in the building code.
In Florida, builders follow a model code known as the Standard Building Code. It is issued by the Southern Building Code Congress, based in Birmingham, Ala. A new version of the code is developed every three years. Every county in Florida routinely adopts the Standard Building Code, except for Dade and Broward counties, which follow their own set of guidelines known as the South Florida Building Code.
In some cases, local governments add their own requirements to the code. In Orlando, for example, the city requires builders to install firefighting sprinklers in buildings higher than four stories, Orlando building official Bill Neese said.
Adhering to the building code is mandatory for contractors. Every house under construction must undergo four inspections by city or county building inspectors, who check to see that the structure is ''up to code.'' If it doesn't pass muster, building officials can refuse to issue a ''certificate of occupancy,'' which is needed so power and water service can be turned on.
Standard building codes were introduced in the 1940s during the post- World War II residential construction boom, said Bill Tangye, executive vice president of the Southern Building Code Congress. Builders and local government officials realized that certain minimum standards were needed to assure consumers that houses were safely constructed, Tangye said.
The Southern Building Code Congress is one of three model code agencies in the nation. It covers most of the Southeastern United States. In the Northeast and Midwest, the Building Officials Council of America issues a code that sets standards for houses built to withstand freezing weather. In the West, the code issued by the International Conference of Building Officials tells builders how to construct earthquake-proof buildings.
Those three agencies issue standards for all types of construction, commercial and residential. A fourth agency, called the Council of American Building Officials, has a national code that covers only one- and two-family dwellings. As with all codes, the council's standards take effect only where local governments adopt them.
Within the housing industry, there is considerable debate over building codes and how they affect building costs, and ultimately, housing prices for consumers.
Tangye of the Southern Building Code Congress said building codes are only minimum standards that pertain more to sound construction methods than they do to building costs. He also said the codes allow builders a certain amount of flexibility that can save them money as long as the house is structurally sound.
''Everytime a builder will show me where the code drives his costs up, I'll show him a dozen areas where the code saves him money,'' Tangye said.
Orange County building director Hewes said he has heard complaints from some contractors about how the Standard Building Code requires solid doors -- which are more expensive than hollow core doors -- to be installed in outside entryways.
''My response to them is that is that if they had a burglar outside, wouldn't they want a door that somebody couldn't put their foot through,'' Hewes said. ''That certainly saves them money in the long run.''
But Dan Cammer, code and standard specialist for the National Home Builders of America, in Arlington, Va., said the 13,000-member association spends a great deal of time reviewing proposed changes in the various model codes checking to determine if they would cost builders more money and drive up home prices.
Cammer said the association also urges changes in codes that can lower a builder's costs. For example, Cammer said, the NAHB recently persuaded the Council of American Building Officials to adopt a new plumbing code -- which is not in effect in Florida -- that allows builders to use narrower pipes in a home's solid waste disposal system.
That may not sound too important, but Cammer said the change could save builders, and ultimately home buyers, $300 to $700 in the price of a home.
For more information on how building codes affect construction methods, write to the Southern Building Code Conference, 900 Montclair Road, Birmingham, Ala. 32513.