Get Permit-Ready ADU Structural & Civil Plans in 2-3 Weeks

Planning an Accessory Dwelling Unit (ADU) or Junior ADU (JADU) in Florida? Our structural engineers cover the full process — site inspections, structural calculations, detailed structural plans, and the permit sets your project needs for construction approval.

Licensed FL Engineers

Same-Day Quote

2-3 Weeks Delivery

Highly Responsive

Permit Guarantee⁽¹⁾

Fixed Transparent Pricing

STATEWIDE ADU SERVICES

Professional ADU Structural Engineering Services Across Florida

Accessory Dwelling Units (ADUs) are a smart way to add rental income, house family members, and increase property value. But building one in Florida takes careful structural planning for hurricane wind loads, flood zone requirements, and your city or county's local ADU rules. ProStruct Engineering provides licensed structural engineering for attached, detached, garage, and junior ADUs statewide, all designed to the Florida Building Code.

Why Choose Our ADU Services?

Jurisdiction-Specific ADU Expertise

Florida ADU rules are set locally, so requirements vary by city and county. We design to your jurisdiction's standards and flag flood zone issues early, such as restrictions on converting a garage below the base flood elevation into living space.

Hurricane-Ready, Permit-Ready Plans

Complete structural calculations and drawings for your building department, including foundation design, framing or CMU walls, and wind uplift connections for a continuous load path.

Fast 2–3 Week Turnaround

Quick project delivery without compromising quality or compliance with Florida building standards.

Click on any county on the map to view ADU structural services and local requirements in your area.

Select Your County

Click on any county on the map to view ADU structural services and local requirements in your area.

Types of Accessory Dwelling Units (ADUs) in Florida

An ADU in Florida can be a guest house, in-law suite, garage apartment, or backyard cottage. Each type has its own structural requirements. Our engineers design every ADU to the Florida Building Code for hurricane wind loads and flood zone requirements, and to your city or county's local ADU rules.

Junior ADU (In-Law Suite)

A smaller living unit, typically under 500 sq. ft., created within the existing home by converting a bedroom or unused space. Structural work often includes new openings, load-bearing wall changes, and framing modifications.

Attached ADU

A self-contained unit attached to the main house as an addition. We design the foundation, walls, roof framing, and the tie-in to your existing home, so the addition and house share a continuous wind load path.

Detached ADU (Guest House)

A standalone backyard cottage or guest house separate from the main home. We engineer the complete structure, including foundation, CMU or wood-frame walls, and roof with hurricane tie-downs, as a new building.

Garage Conversion ADU

Converting an existing garage into living space is one of the most affordable ADU options. We assess the existing slab, walls, and roof, and flag flood zone limits early, since garages below base flood elevation often can't be converted to habitable space.

Above-Garage ADU (Garage Apartment)

A second-story garage apartment built over a new or existing garage. We verify that the garage walls and foundation can carry the added loads, then design the floor framing, walls, and wind uplift connections.

Elevated ADU for Flood Zones

In flood-prone and coastal areas, an ADU may need to be raised above base flood elevation. We design elevated foundations on stem walls or piles so your ADU meets flood requirements and stays protected.

Detached ADU guest house on a Florida residential property

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

Our engineers visit your site to assess conditions that affect the structural design of your home, addition, ADU, deck, or retaining wall, including soil, drainage, existing framing, and flood zone exposure.

Structural Calculations

We perform load calculations to determine how your structure will resist hurricane-force winds, wind uplift, and gravity loads under the Florida Building Code. These calculations set the size and connections of beams, columns, load-bearing walls, and foundations, including projects in the High-Velocity Hurricane Zone (HVHZ) in Miami-Dade and Broward.

Structural Plans

Based on the calculation results, our engineers prepare structural plans for your framing, foundation, and roof systems, with the tie-down and connection details Florida building officials expect.

Structural Permit Sets

Each permit-ready package includes detailed drawings, specifications, calculations, and supporting documentation, signed and sealed, and formatted for submission to your city or county building department to obtain a building permit.

Construction Administration

We provide construction administration support throughout your build by responding to Requests for Information (RFIs), performing submittal reviews, addressing substitution requests, and conducting structural observations. This keeps construction aligned with the approved plans and the Florida Building Code, and helps resolve unforeseen structural issues quickly.

Get Permit-Ready ADU Structural & Civil Plans in 2-3 Weeks

Get Permit-Ready ADU Structural & Civil Plans in 2-3 Weeks