What do "building systems" include?

Building systems are essential components of a structure that facilitate its functionality and livability. The term specifically refers to the plumbing, electrical, and HVAC (heating, ventilation, and air conditioning) systems within a building. Each of these systems plays a critical role in maintaining comfort, safety, and operational efficiency.

Plumbing systems provide necessary water supply and waste removal, ensuring hygiene and convenience for occupants. The electrical system is crucial for powering lights, appliances, and other devices that make a building functional. HVAC systems are integral for temperature control and indoor air quality, significantly impacting occupant comfort.

While structural load-bearing components, exterior walls, roofing materials, and elements of a building’s façade are important, they fall outside the definition of what is typically classified as building systems. They contribute to the overall integrity and appearance of a building, but they do not perform the same essential service functions as plumbing, electrical, and HVAC systems. Therefore, the correct answer highlights the systems that are vital for the operation and comfort of the occupants.