Understanding the different engineers involved in your project—and when each one comes into play
Introduction
Most construction projects will involve more than just architects and contractors. Depending on what you’re building and where, several types of engineers may be required, some for safety, others for code compliance, and others for permitting.
This page breaks down the common engineering disciplines you may encounter during preconstruction. You’ll learn what each engineer does, when they typically get involved, and how they fit into either a traditional design-bid-build process or a design-build model.
You won’t need to manage all of this yourself, but understanding these roles will help you communicate more clearly with your team and know what to expect as your project moves forward.
Structural Engineer
A structural engineer ensures your building will stand up to gravity, wind, earthquakes, and everyday use. They design the core framework: beams, posts, foundations, and load-bearing walls, based on your project’s size, shape, and materials.
What they do:
- Size and locate beams, posts, footings, and foundations
- Review framing layouts, floor loads, and shear walls
- Provide structural calculations for permit submittals
- Recommend framing materials and methods for complex designs
When they get involved:
- After schematic design is approved
- Before final construction drawings are submitted
- Sooner if the project includes hillside work or major spans
How they’re brought in:
- Typically managed by the architect
- In design-build, often included in the contractor’s team
- May also be hired directly by the project owner for remodels involving structural changes
Civil Engineer
A civil engineer focuses on everything happening outside the building: grading, drainage, stormwater management, erosion control, and utility layout. They’re often required for permitting and can be involved very early in the process.
What they do:
- Prepare site plans for grading and drainage
- Ensure stormwater is managed per local code
- Design utility connections and coordinate with city services
- May include erosion control plans, especially for hillsides or near waterways
When they get involved:
- Early, often before the architect completes the first concept
- Often required when slope, water flow, or large-scale site work is involved
How they’re brought in:
- Managed by the architect or directly by the owner
- In design-build, civil is sometimes in-house or subcontracted early on
Geotechnical Engineer (Soils Engineer)
Geotechnical engineers analyze the condition of the soil under your site. Their findings determine how deep the foundation must go, whether you need special drainage, and what structural reinforcements are needed.
What they do:
- Drill or bore into the site and test soil composition
- Evaluate bearing capacity and water table levels
- Provide recommendations for foundation type, retaining walls, and soil prep
- Write a geotechnical report (usually required for permitting)
When they get involved:
- One of the first engineers to get involved, often before design starts
- Needed before structural or civil design is finalized
How they’re brought in:
- Managed by the architect, civil engineer, or owner
- Often coordinated early by a design-build contractor if applicable
MEP Engineer (Mechanical, Electrical, Plumbing)
MEP engineers design the internal systems that power your home: heating and cooling, electrical, and plumbing. Their plans ensure the building meets energy code, performs efficiently, and coordinates with the architecture.
What they do:
- Design HVAC, lighting, power, plumbing, and equipment locations
- Ensure code compliance (especially energy efficiency and ventilation)
- Coordinate with architects and structural engineers to avoid conflicts
- Provide load calculations and system specs
When they get involved:
- Usually after the floor plan and massing are set
- Earlier if the project involves complex systems, energy goals, or limited space for equipment
How they’re brought in:
- Managed by the architect or hired directly by the owner
- In some cases, MEP design may be handled in-house or through subcontractors with engineering support
Specialty Engineers (As Needed)
Depending on the type of project, location, or requirements from the city, you might also work with:
Fire Protection Engineer
- Needed in commercial and multi-unit residential for sprinkler system design
Energy Consultant / Title 24 Specialist
- Required in California and other states for energy code documentation
Landscape or Irrigation Engineer
- Occasionally required by zoning or city ordinance on larger projects
Seismic or Wind Engineer
- Required in some areas with stricter structural or hazard zone requirements
Environmental Engineer
- For sites near wetlands, coastlines, or in protected zones
Low Voltage / AV Consultant
- On high-end projects with integrated technology or security systems
How they’re brought in: Usually through referrals by your architect, engineer, or builder. Most of these specialists are only involved when a specific need arises.
How Engineering Is Coordinated
Engineering is rarely done in isolation. Every discipline depends on accurate input from others:
- Structural engineers rely on soils data from geotechnical reports
- Civil engineers use survey data and coordinate with drainage design
- MEP engineers need final floor plans and architectural layouts
- All engineers may revise their work during plan check or city review
The architect often manages the engineering team and integrates all drawings into the permit set.
If your team is fragmented, it’s important to designate someone, usually the architect or a project manager, to make sure everyone stays in sync.
When to Involve Engineers
Engineer | Typically Involved At |
Geotechnical | Early (pre-design or schematic) |
Civil | Early (site planning) |
Structural | After layout is confirmed, before permits |
MEP | Mid-to-late design, before construction docs |
Specialty Engineers | As needed, often closer to permit submittal |
Delays in involving the right engineer can hold up permitting or require design changes later. Talk to your team early to confirm who’s needed and when.
What’s Next: Do You Need Plans or Not?
By now, you’ve gathered or at least understand survey data, explored your site conditions, and learned how different engineers may support your project. The next step is determining whether your project requires formal plans, or if a detailed scope of work may be enough.
Continue to Do You Need Plans or Not? to learn how to assess your project type, location, and goals to figure out what documentation you’ll need to move forward.