Building Officials divide various activities that take place in buildings up in to different "occupancies", e.g. residential, commercial, hazardous, assembly, etc. Live/work is normally seen as a combination of residential and commercial occupancy. Most building codes automatically require a fire wall between those two occupancies, which flies in the face of what many live/work units are -- one large open space where both activities take place. However, calmer minds have prevailed, with relative unanimity.

Those writing live/work building codes have usually taken a two-pronged approach to omission of an occupancy separation between the live and work portions of a live/work space. First, the potential hazard created by the commercial occupancy is further limited in such code interpretations to the more benign activities such as arts, crafts, and home office type uses. Logically, the presence of an employee performing such work poses no more hazard than that of the resident doing so. Secondly, regardless of whether it might otherwise be required, provision of an automatic sprinkler system in a building is intended to provide that extra level of protection to compensate for the omission of the occupancy separation within units. Other strategies as an alternate to sprinklers would be to require the building to be one-hour rated, or to require that walls separating individual units and those between units and corridors be two-hour rated. This latter option has worked well because it also ensures good sound insulation between the units. Therefore, increased protection combined with reduced hazard activity is a potent combination which is now acceptable in numerous jurisdictions.

The above discussion relates to live-with™ units, in which the entire unit is one open space. Live-near™ units may be the configuration of choice for numerous reasons, some of which are life safety (read: code) related. When the work activity is sufficiently hazardous to be incompatible with residential occupancy -- whether or not it is officially "hazardous" occupancy -- a wall, probably a fire wall, between the living and work portion is desirable. Examples of such work activities would be welding, large wood shops or work involving use or storage of significant amounts of hazardous materials such as compressed gages, fuel, or various industrial chemicals.

In addition to hazardous materials and processes, there is at least one other reason for requiring a separation between living and working spaces. In live/work units which allow employees, when the number of employees exceeds some small number -- say five -- it seems inappropriate for such a business to be sharing the same kitchen, bathroom, etc. with the residents of that space. The separation between the two need not necessarily be fire-related, and the best way to predict how many employees might be in a space is by area. So it is suggested that live/work units that permit employees and whose work area is over 2000 square feet (this number may vary) be required to be live-near™ i.e. to have a wall or floor separating the live and work portions of the unit.