It is typically treated as being legally coupled with the dwelling it surrounds despite the fact that it might commonly be considered "outdoors".
This distinction is important under US law for cases dealing with burglary and with self defense under the Castle Doctrine. Under Florida law, burglary encompasses the English common-law definition and adds (among other things) curtilage to the protected area of the dwelling into which intrusion is prohibited. Similarly, a homeowner does not have to retreat within the curtilage under Florida's Castle Doctrine.
The curtilage (like the home) provides a reasonable expectation of privacy and hence is protected from unreasonable search and seizure under the Fourth Amendment of the U.S. Constitution. See Open fields doctrine for how courts distinguish curtilage and "open fields", with the latter not providing privacy.
The listing for each building does not define the specific curtilage, and so the line of the curtilage can be a matter of contention. Various factors need to be taken into account, such as the ownership of the land, physical boundaries, such as fences, walls and hedges, and the historic use of the land. Some Local Planning Authorities (such as Bournemouth) publish provisional curtilages, to assist property owners; but frequently curtilages are left undefined until such time as they may be challenged.