Yes. An accessory dwelling unit is a habitable structure and must meet the same structural code requirements as a primary residence. Your local building department will require PE-stamped structural calculations and construction drawings before issuing a building permit. This applies to detached new-build ADUs, garage conversions, and above-garage additions. Platform Engineering provides the complete structural engineering package required for permit approval.

Texas HB 1399, passed in 2023, eased restrictions on accessory dwelling units in many Texas jurisdictions. The bill limited the ability of municipalities to prohibit ADUs outright on residential lots and relaxed certain regulatory barriers. However, the bill did not eliminate the requirement for building permits, structural engineering, or code compliance. Each local jurisdiction still enforces its own permitting process, setback requirements, and occupancy standards. Platform Engineering stays current with how DFW-area building departments are interpreting and applying HB 1399.

It depends on the design and condition of the existing slab. Garage slabs are typically thinner and reinforced differently than residential living space foundations, and they may not have been designed for the insulation, plumbing, or occupancy loads associated with habitable space. Our PE evaluates the existing slab, determines its capacity relative to the proposed use, and designs any reinforcement or supplemental foundation work required to meet code.

Pricing depends on the ADU project type and complexity. A straightforward garage conversion typically requires less engineering than a ground-up detached ADU with a new foundation. An above-garage addition involves evaluation of the existing structure plus new second-story design. We provide a clear, itemized proposal after reviewing your project details so you understand the investment before work begins. Contact us at +1-469-405-1710 for a project-specific quote.

Most ADU structural packages are completed within two to four weeks from receipt of complete project information, depending on the project type and complexity. Garage conversions on the simpler end of that range and ground-up detached ADUs on the longer end. We provide a specific timeline in every proposal and coordinate with your project schedule.

Potentially, but the existing garage structure must be evaluated by a Professional Engineer first. The existing foundation, walls, and roof framing were designed for garage loads — not for the additional weight and occupancy demands of a second-story living space. Our PE analyzes the existing structure, determines what modifications or reinforcements are needed, and designs the second-story addition to ensure the combined structure meets current building code requirements.