A structural engineer is a specialized civil engineer who designs and analyzes the load-bearing elements of buildings, bridges, tunnels, and other structures to make sure they can safely support weight and withstand environmental forces. While architects focus on how a building looks and functions, a structural engineer focuses on whether it will stand up. If you’re wondering whether you need one for a home project, considering it as a career, or just trying to understand what they do, here’s a full breakdown.
What a Structural Engineer Actually Does
A structural engineer’s core job is making sure a structure won’t collapse, sag, or deform under the loads it’s expected to carry. That includes the weight of the building itself (dead load), the weight of people, furniture, and equipment inside it (live load), and external forces like wind, snow, and earthquakes.
Day to day, that work can look very different depending on the project. On new construction, a structural engineer calculates the weight of a proposed structure, selects appropriate materials (steel, concrete, timber, masonry), and designs the beams, columns, foundations, and connections that hold everything together. They test construction materials to confirm they can handle the expected stresses. They also review an architect’s design to verify its safety and structural integrity, submit permit applications, and ensure the project meets building codes.
On existing buildings, structural engineers perform site surveys, inspect foundations and framing, and evaluate whether a structure can handle a proposed renovation, like removing a wall or adding a second story. They also assess damage after events like earthquakes, floods, or fires.
How They Differ From Architects
Architects and structural engineers work closely together, but their responsibilities are distinct. An architect focuses on the layout, aesthetics, and overall functionality of a building. They create the conceptual design, coordinate with the client, specify materials for appearance and function, and estimate project costs. A structural engineer then takes that design and figures out how to make it physically stand up. They determine where load-bearing walls go, how thick the foundation needs to be, what size steel beams are required, and how the structure will handle lateral forces like wind.
Think of it this way: the architect decides the building should have an open floor plan with floor-to-ceiling windows. The structural engineer figures out how to support the roof and upper floors without interior walls blocking that open space.
Structural vs. Civil Engineering
Structural engineering is a specialization within civil engineering. Civil engineering is the broader field covering the design and construction of infrastructure, including roads, water systems, and buildings. Structural engineering narrows that focus specifically to load-bearing structures like skyscrapers, dams, bridges, and tunnels, with deep expertise in how forces move through materials and connections.
Specializations Within the Field
Structural engineers often develop expertise in a particular niche. Some of the most common specializations include:
- Seismic engineering: Designing structures to withstand earthquakes, which involves specialized knowledge of how ground motion affects buildings and how to use flexible connections, base isolation, and reinforced materials to prevent collapse.
- Bridge engineering: Designing and evaluating bridges, which requires expertise in long-span structures, dynamic loads from traffic, and environmental exposure to wind and water.
- Forensic engineering: Investigating why structures failed. Forensic engineers analyze collapsed or damaged buildings, review construction documentation, and conduct site inspections to identify the causes of failure. Their findings often end up in legal proceedings or inform updated building codes.
- Sustainable design: Integrating eco-friendly materials and practices into structural design to minimize energy use, waste, and environmental impact while maintaining safety standards.
Education and Licensing Requirements
Becoming a structural engineer requires a bachelor’s degree in civil or structural engineering, typically a four-year program covering physics, calculus, materials science, and structural analysis. Many structural engineers also earn a master’s degree, which is increasingly expected for advanced structural design work.
After graduating, the path to full licensure follows a multi-step process. You first pass the Fundamentals of Engineering (FE) exam, which you can take during your senior year or shortly after graduation. Then you work under a licensed engineer for several years to gain qualifying experience, typically four years, though requirements vary by state. After accumulating enough experience, you sit for the Professional Engineer (PE) exam to earn your PE license.
Some states offer an additional Structural Engineer (SE) license, which represents a higher level of specialization. Earning an SE license typically requires passing the NCEES PE Structural Exam and demonstrating additional qualifying work experience with professional references. In states that offer the SE designation, certain types of structural work, particularly on hospitals, schools, and other critical buildings, may require an SE-licensed engineer rather than a general PE.
When Homeowners Need One
Most people encounter structural engineers when buying, renovating, or repairing a home. Here are the situations where hiring one makes sense:
Foundation problems. Cracks in your foundation walls or floor slabs are the most common trigger. Not every crack is serious, but a structural engineer’s assessment becomes important when cracks are wider than 1/8 inch, are actively growing or widening, show visible displacement between edges, appear in load-bearing walls, or leak water. Multiple cracks clustered in the same area or fresh cracks appearing in a previously stable building also warrant evaluation.
Sagging or uneven floors. If marbles roll on their own, you see visible dips when viewing the floor from different angles, gaps appear between baseboards and flooring, or the slope exceeds 1 to 2 inches over 20 feet, the floor structure may be compromised. A structural engineer can determine whether the issue is cosmetic or indicates failing joists, beams, or foundation settlement.
Sticking doors and windows. A single sticky door is usually just humidity or normal settling. But when three or more doors or windows stick persistently, the problems worsen quickly, or misalignment appears suddenly after a storm, the building’s frame may be shifting. Visible gaps between doors and their frames, doors that swing open on their own, and cracks at the corners of window frames all point to potential structural movement.
Bowing or leaning walls. A wall bowing inward by even 1/4 inch needs professional evaluation. Horizontal cracks along mortar joints, separation between walls and the ceiling, and loose bricks are all warning signs of lateral pressure from soil, water, or structural failure.
Renovation projects. Any renovation that involves removing a wall, cutting into a floor, adding a story, or significantly changing a building’s layout should involve a structural engineer. They determine whether a wall is load-bearing and, if so, design the beam or header needed to replace it. Most local building departments require stamped structural drawings from a licensed engineer before issuing permits for this type of work.
Salary and Job Outlook
The Bureau of Labor Statistics groups structural engineers under civil engineers. The median annual wage for civil engineers was $99,590 as of May 2024, with the lowest 10 percent earning less than $65,920 and the highest 10 percent earning more than $160,990. Structural engineers with an SE license or specialized expertise in areas like seismic design often earn toward the higher end of that range.
Employment of civil engineers is projected to grow 5 percent from 2024 to 2034, faster than the average for all occupations. About 23,600 openings are projected each year over the decade, driven by the ongoing need to maintain and replace aging infrastructure, build new facilities, and adapt structures to changing environmental conditions. Structural engineers with expertise in seismic retrofitting, sustainable design, or forensic investigation tend to be in particularly strong demand.