The types of construction found in nursing homes and assisted living facilities are as diversified as are communities. These buildings can be built of fire resistive material and be fully sprinklered, or ordinary, frame, or mixed construction with minimal protective systems. It is common practice in many areas to convert large single family dwellings for this use. Converted structures can contain vertical voids that carry the utilities upward through the structure. These voids are seldom fire stopped, and should a fire extend into these spaces, it will threaten all areas above. Older converted buildings may be designed in a dormitory style with rooms or apartments containing multiple occupants. This layout allows the carelessness of one occupant to threaten the lives of his or her roommates. The different types of construction are type 1, type 11, type 111, and type V. Type 1 offers excellent fire resistance, aiding in evacuation and providing safer conditions for fire crews. However, it may create challenges in locating and accessing concealed fire spread. Type 11 is similar but can deteriorate quickly under extreme heat. Type 111 poses risks of fire extension through concealed voids, requiring advanced training in overhaul and ventilation. Type V is the most vulnerable, often used in smaller or residential style facilities, and demands swift action due to rapid fire spread. Each type requires specific training for fire officers in strategy, risk assessment, and command under realistic conditions.