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STATEWIDE ADU SERVICES

Professional ADU Structural Engineering Services Across California

Accessory Dwelling Units (ADUs) offer a smart way to maximize property value, create additional housing, and adapt to changing family needs. However, successful ADU development requires careful structural planning and a deep understanding of California's building codes.

Why Choose Our ADU Services?

County-Specific Expertise

We understand local building codes, zoning regulations, and permit requirements for each California county.

Complete Permit-Ready Plans

Full structural calculations and structural engineering plans ready for your county's building department submission.

Fast 2-3 Week Turnaround

Quick project delivery without compromising on quality or compliance with California ADU regulations.

Click on any county on the map to view specific ADU services and local requirements.

Select Your County

Serving all 58 California counties with expert ADU structural engineering

Types of Accessory Dwelling Units (ADUs)

Single-family ADUs are secondary housing units that are located on the same lot as a single-family home. These units are also sometimes referred to as granny flats, in-law suites or backyard cottages.

Types of Accessory Dwelling Units (ADUs)

Single-family ADUs are secondary housing units that are located on the same lot as a single-family home. These units are also sometimes referred to as granny flats, in-law suites or backyard cottages.

Junior ADU (JADU)
These are smaller units that are typically less than 500 square feet and are often created by converting a single room within the primary residence.
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Attached ADU
These are units that are attached to the main house, often as an addition or a converted garage.
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Detached ADU
These are stand-alone structures that are separate from the primary residence. They can be built on the same lot as the main house or on a separate lot.
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Basement ADU
These are units that are located in the basement of the primary residence.
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Garage ADU
These are units that are built above or within an existing garage.
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Multi-family ADU
Sometimes referred to as a secondary suite, these ADUs are designed to be part of a larger multi-family residential building, such as an apartment complex or duplex.
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Accessory dwelling unit exterior

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Schedule a Free Consultation With One of Our Expert Structural Engineers for Your ADU Project.

What We Do?

Our skilled structural engineers can provide the following services for your ADU (or JADU) project:

Structural Site
Inspections

Structural
Calculations

Structural
Plans

Structural Permit
Sets

Construction
Administration

Structural Site Inspections

This involves a site visit to assess factors that may impact the structural design of your ADU (or JADU), or the stability of your home if it is a JADU or attached ADU.

Structural Calculations

Load calculations are performed to assess the static and dynamic stresses your ADU structure will need to endure during seismic activity. This helps determine the appropriate sizes and shapes of structural members like beams, columns, load-bearing walls, and foundations.

Structural Plans

Based on structural load calculation results, our engineers develop plans for your ADU's structural components, such as framing, foundation, and roof systems.

Structural Permit Sets

These typically include detailed drawings and specifications of your ADU's structural components, as well as calculations and other documentation required by local building departments to obtain a construction permit.

Construction Administration

Our engineers can provide construction administration services, which include guidance throughout the build. This encompasses responding to RFIs, performing submittal reviews, addressing substitution requests, and conducting structural observations.