Structural engineering involves the analysis and design of the built environment (buildings, bridges, equipment supports, towers and walls). Those concentrating on buildings are sometimes informally referred to as "building engineers". Structural engineers require expertise in strength of materials, structural analysis, and in predicting structural load such as from weight of the building, occupants and contents, and extreme events such as wind, rain, ice, and seismic design of structures which is referred to as earthquake engineering. Architectural Engineers sometimes incorporate structural as one aspect of their designs; the structural discipline when practiced as a specialty works closely with architects and other engineering specialists.
Mechanical engineering and electrical engineering engineers are specialists, commonly referred to as (mechanical, electrical, and plumbing) when engaged in the building design fields. Also known as "building services engineering" in the United Kingdom, Canada, and Australia. Mechanical engineers often design and oversee the heating, ventilation and air conditioning (HVAC), plumbing, and rain gutter systems. Plumbing designers often include design specifications for simple active fire protection systems, but for more complicated projects, fire protection engineers are often separately retained. Electrical engineers are responsible for the building's power distribution, telecommunication, fire alarm, signalization, lightning protection and control systems, as well as lighting systems.
In many jurisdictions of the United States, the architectural engineer is a licensed engineering professional. Usually a graduate of an architectural engineering university program preparing students to perform whole-building design in competition with architect-engineer teams; or for practice in one of structural, mechanical or electrical fields of building design, but with an appreciation of integrated architectural requirements.
Formal architectural engineering education, following the engineering model of earlier disciplines, developed in the late 19th century, and became widespread in the United States by the mid-20th century. With the establishment of a specific "architectural engineering" NCEES Professional Engineering registration examination in the 1990s, and first offering in April 2003, architectural engineering became recognized as a distinct engineering discipline in the United States.
In most license-regulated jurisdictions, architectural engineers are not entitled to practice architecture unless they are also licensed as architects, and may be restricted from the practice of structural engineering on specific types of higher importance buildings such as hospitals. Regulations and customary practice vary widely by region or city.