Reference · 82+ Terms
Plain-language definitions for structural, MEP, civil, geotechnical, and permitting terms used in commercial and industrial engineering — written by licensed professional engineers.
Accessibility in buildings refers to design requirements that ensure people with disabilities can ap…
The Authority Having Jurisdiction (AHJ) is the organization, office, or individual responsible for e…
Allowable bearing pressure is the maximum load per unit area that a soil or rock formation can suppo…
An anchor bolt is a threaded steel fastener embedded in concrete that attaches structural elements —…
ASCE 7 is the American Society of Civil Engineers standard that specifies the minimum loads — dead, …
ASHRAE is the professional society that publishes the standards governing HVAC, refrigeration, build…
Antiterrorism/Force Protection (ATFP) refers to design measures required on U.S. military and federa…
The Build America, Buy America Act (BABA) requires that iron, steel, manufactured products, and cons…
A beam is a horizontal structural member that carries loads primarily through bending, spanning betw…
Bearing capacity is the maximum load per unit area that a soil or rock mass can support before shear…
Building Information Modeling (BIM) is a process for creating and managing digital representations o…
A braced frame is a structural system that resists lateral forces — wind and seismic — through diago…
Computer-Aided Design (CAD) is the use of software to create, modify, and document engineering drawi…
A Certificate of Occupancy (CO) is a document issued by the local building department confirming tha…
A change of occupancy occurs when a building or space is converted from one use classification to an…
A chilled water system is a central HVAC cooling approach in which a chiller plant produces chilled …
A Concrete Masonry Unit (CMU) is a precast hollow or solid concrete block used in walls and partitio…
A collector (also called a drag strut) is a structural element — typically a beam, chord, or reinfor…
A column is a vertical structural member that carries compressive loads from floors, roofs, and beam…
Soil compaction is the process of mechanically increasing the density of soil by reducing void space…
Construction administration (CA) is the phase of engineering services in which the engineer of recor…
Dead load is the permanent, static weight of all building materials and fixed equipment that a struc…
A detention basin is a stormwater management facility that temporarily stores runoff from a develope…
A structural diaphragm is a horizontal or nearly horizontal structural element — typically a floor d…
The domestic water system in a building is the network of pipes that delivers potable cold water fro…
Site drainage is the engineered system of graded surfaces, swales, inlets, pipes, and detention or r…
The Division of the State Architect (DSA) is a California state agency that acts as the AHJ for stru…
An Energy Recovery Ventilator (ERV) or Heat Recovery Ventilator (HRV) is a mechanical ventilation de…
EV charging infrastructure provides electrical power to charge plug-in electric vehicles and include…
Expansive soils are clay-rich soils that swell significantly when wetted and shrink when dried, exer…
An emergency or standby generator is a diesel or natural gas fueled engine-generator set that provid…
A grade beam is a horizontal reinforced concrete beam constructed at grade level (at or just below t…
Grading is the earthwork process of reshaping the ground surface of a site to achieve design elevati…
Grease exhaust systems capture cooking effluent — grease-laden air, heat, steam, and combustion prod…
A holdown is a metal connector that anchors the end post of a shear wall to the foundation or to the…
HVAC stands for Heating, Ventilation, and Air Conditioning — the systems that control temperature, h…
The International Building Code (IBC) is the model building code published by the International Code…
The International Energy Conservation Code (IECC) is the model energy code published by the ICC that…
An impervious surface is any paved or covered ground surface — roofs, parking lots, roads, sidewalks…
The Lateral Force Resisting System (LFRS) is the collection of structural elements — shear walls, mo…
A lintel is a horizontal structural member that spans over a door, window, or wall opening and carri…
Live load is the variable, non-permanent load on a structure caused by occupants, furniture, equipme…
An HVAC load calculation determines the amount of heating and cooling energy required to maintain a …
Make-up air (MUA) is supply air introduced into a space to replace air that has been exhausted, main…
A mat (or raft) foundation is a thick reinforced concrete slab that covers the entire building footp…
Medical gas systems distribute piped oxygen, medical air, nitrous oxide, vacuum, and other specialty…
MEP refers to the three primary building systems engineering disciplines: Mechanical (HVAC), Electri…
A moment frame is a structural system that resists lateral wind and seismic forces through the bendi…
A panel schedule is an electrical drawing or table that lists all circuit breakers in a panelboard, …
A Professional Engineer (PE) is a licensed engineer who has met the education, experience, and exami…
Permit drawings are the set of engineering drawings — structural, MEP, civil, and sometimes architec…
A drilled pier (also called a caisson or drilled shaft) is a deep foundation element formed by drill…
Plan check (or plan review) is the process by which the building department or a third-party plan re…
Post-tensioned (PT) concrete is a form of prestressed concrete in which high-strength steel tendons …
A retaining wall is a structure designed to hold back soil, rock, or other material on one side whil…
A Request for Information (RFI) is a formal written question submitted by a contractor to the design…
A Rooftop Unit (RTU) is a packaged HVAC system mounted on a building's roof that contains all heatin…
A sanitary riser diagram is a schematic drawing showing the vertical arrangement of plumbing waste a…
The Seismic Design Category (SDC) is a classification (A through F) assigned to a building based on …
Seismic load is the inertial force exerted on a building during an earthquake, caused by the acceler…
A seismic retrofit is a structural modification of an existing building to improve its ability to re…
Settlement is the vertical downward movement of a foundation or soil mass under load, caused by comp…
A shear wall is a vertical structural element — typically plywood-sheathed wood framing, reinforced …
A slab-on-grade (SOG) is a concrete floor slab placed directly on prepared subgrade, used as the gro…
A soil boring is a subsurface investigation technique in which a drilling rig advances a hollow rod …
A solar photovoltaic (PV) system converts sunlight directly into electricity using semiconductor pan…
A storm drain system is the network of inlets, pipes, and channels that collects surface runoff from…
Stormwater management encompasses the planning, design, and permitting of systems that control the q…
A tenant improvement (TI) is a construction project that modifies an existing commercial space to su…
Tilt-up construction is a method of building construction in which concrete wall panels are cast hor…
Title 24 refers to the California Code of Regulations Title 24, which contains the California Buildi…
A truss is a structural assembly of individual members arranged in a triangulated pattern that toget…
Unified Facilities Criteria (UFC) are the design and construction standards published by the U.S. De…
An Uninterruptible Power Supply (UPS) is an electrical device that provides emergency power to conne…
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