Selecting the appropriate structural system is one of the most important decisions in any construction project. The structural system determines the building's strength, durability, seismic performance, construction cost, and long-term maintenance requirements.

In California, particularly throughout Orange County, structural systems must be designed to withstand seismic activity while meeting strict building code requirements. The most common structural systems include wood framing, structural steel, reinforced concrete, masonry construction, and engineered hybrid systems.

A structural system is the framework that supports all loads imposed on a building, including:

• Dead Loads (permanent weight of the building)
• Live Loads (occupants, furniture, equipment)
• Wind Loads
• Seismic Loads
• Snow Loads (limited in most of Southern California)

The structural engineer designs the building to safely transfer these loads into the foundation and ultimately into the ground.

Wood framing is by far the most common structural system used for residential construction throughout Orange County.

• Single-family homes
• ADUs
• Garage Conversions
• Duplexes
• Townhomes
• Low-rise apartment buildings

Examples include:

• 2x4 Studs
• 2x6 Studs
• 4x4 Posts
• 6x6 Posts

Includes:

• LVL (Laminated Veneer Lumber)
• PSL (Parallel Strand Lumber)
• Glulam Beams
• I-Joists

These products provide greater strength and dimensional stability compared to traditional lumber.

• Lower construction cost
• Faster installation
• Easy modification during remodeling
• Readily available materials
• Excellent for residential projects

• Susceptible to moisture damage
• Potential termite exposure
• Limited spans compared to steel
• Height restrictions

Orange County residential wood framing typically ranges from:

$15–$35 per square foot of framed area depending on complexity.

Structural steel is commonly used for commercial buildings, mixed-use developments, and custom homes requiring large open spaces.

• Commercial buildings
• Industrial buildings
• Warehouses
• Luxury custom homes
• Multi-story developments

Used for major load-bearing spans.

Hollow Structural Sections used for columns and architectural framing.

Support heavy vertical loads.

Provide seismic resistance in earthquake-prone regions.

• Extremely strong
• Long spans without interior supports
• Excellent seismic performance
• Reduced structural depth
• Faster erection on large projects

• Higher material costs
• Requires specialized fabrication
• Fireproofing may be required
• More expensive engineering

Structural steel systems generally cost:

$30–$80+ per square foot depending on complexity.

Concrete structures provide exceptional durability and strength.

• Parking structures
• Mid-rise buildings
• High-rise buildings
• Podium construction
• Foundations
• Retaining walls

Contain steel reinforcing bars (rebar).

Transfer structural loads.

Support vertical loads.

Provide lateral resistance during earthquakes.

• Exceptional durability
• Excellent fire resistance
• High compressive strength
• Long service life

• Higher labor costs
• Longer construction schedule
• Increased foundation requirements
• Heavier structure

Concrete structural systems often range:

$40–$120+ per square foot.

Masonry systems utilize concrete masonry units (CMU), brick, or stone.

• Commercial buildings
• Retaining walls
• Architectural facades
• Fire walls

• Excellent fire resistance
• Durable
• Low maintenance
• Long lifespan

• Heavy structure
• Requires seismic reinforcement
• Higher labor requirements

Post-tension systems use high-strength steel cables embedded within concrete.

After curing, cables are tensioned to increase structural performance.

• Parking structures
• Podium buildings
• Large residential foundations
• Commercial buildings

• Longer spans
• Reduced cracking
• Thinner slabs
• Lower structural weight

Many modern California buildings combine multiple structural systems.

Examples include:

Common for apartment developments.

• Concrete podium at ground level
• Wood-framed residential units above

Frequently used in luxury custom homes.

Used for large commercial developments.

California has some of the strictest seismic codes in the world.

Structural systems must account for:

• Ground acceleration
• Lateral forces
• Building drift
• Shear resistance
• Foundation movement

Engineers commonly use:

• Shear walls
• Moment frames
• Hold-down systems
• Anchor bolts
• Drag struts
• Structural diaphragms

These components help buildings resist earthquake forces.

Regardless of structural type, every building requires an appropriate foundation.

Most common for residential construction.

Common in older homes and hillside projects.

Used on steep lots and hillside developments.

Common in areas with expansive soils.

For most residential projects, including:

• Garage Conversions
• ADUs
• Room Additions
• Single-Family Homes

Wood framing remains the most economical and widely accepted solution.

However, structural steel may be incorporated for:

• Large openings
• Sliding glass walls
• Open floor plans
• Cantilevered structures

The ideal structural system depends on:

• Budget
• Building size
• Architectural design
• Site conditions
• Seismic requirements
• Construction schedule

For most residential construction in Orange County:

Best for:

• Homes
• ADUs
• Additions
• Garage Conversions

Best for:

• Large spans
• Luxury homes
• Commercial buildings

Best for:

• Foundations
• Parking structures
• Multi-story developments

Best for:

• Modern custom homes
• Mixed-use projects
• Multi-family developments

California's seismic conditions require carefully engineered structural systems designed to meet strict safety standards. Whether constructing a custom home, ADU, commercial building, or large-scale development, selecting the proper structural system is critical to long-term performance, durability, and cost efficiency.

Jordan Remodeling works with licensed structural engineers and experienced construction professionals to deliver safe, code-compliant, and high-quality construction projects throughout Orange County.