Forensic Engineering & Architecture

YA Engineering Services is a forensic multi-disciplinary firm that specializes in evaluations of existing structures. Our engineers, architects, and non-destructive testing specialists bring decades of experience in conducting forensic investigations. Our President, Richard A. Dethlefs, P.E., S.E., founded the engineering division in January 2019 after spending over twenty years and becoming a Principal at one of the largest and most well-regarded forensic engineering firms in the United States. Our goal with YA is to offer a team of highly qualified, technically excellent engineering professionals who work seamlessly together to service the needs of our clients in the model of an engineering cooperative.

Our quality control procedures require that all analyses, reports, and deliverables receive critical technical and style reviews before issuance. YA provides immediate response to new assignments, performs investigations in a timely manner, and provides comprehensive reports that are clear, concise, and backed by reasonable analyses and recommendations.

Building Envelope

Building envelope systems include roofing, cladding, windows and doors, flashings, weather-resistant barriers, and associated components. YA engineers and architects are experts in investigating and identifying building envelope leaks and failures. This expertise provides YA with a background to develop repair solutions to existing building envelope systems and perform peer reviews for new construction designs. YA professionals also provide litigation support and expert testimony when needed to support our findings.

Damage Assessment, Cause & Origin​

YA specializes in forensic evaluations of damage to existing buildings and structures. Damage can result from any number of causes, including singular events such as earthquakes, hurricanes, wind, fire, floods, and impact; long-term effects such as corrosion, soil settlement, wear and tear, and decay; or human-influenced causes such as design errors, installation defects, and deferred maintenance.

YA professionals have a vast background in forensic evaluations, which enables them to investigate all types of damage to all manner of buildings and structures. YA Damage Assessment Services are provided by experts in structural analysis and finite element modeling, non-destructive and destructive testing methods, mechanical, HVAC, and plumbing systems, marine structures, building envelopes, and code upgrade evaluations.

Comprehensive damage evaluations require an understanding of engineering mechanics, structural behavior, cladding systems, load path, installation methods, and behavioral properties of a wide range of construction materials, including metals, glass, masonry, concrete, wood, sealants, roofing, etc. Although no two damage investigations are identical, the same basic principles apply to all damage evaluations. These principles include documentation of conditions, preservation of evidence, code and document review, structural analysis, testing, and laboratory analysis, and report writing. YA reports clearly describe the investigation and findings and provide concise conclusions that may be easily understood.


Design & Code Review​

YA engineers and architects regularly perform forensic evaluations of existing buildings and are tasked with designing repairs to and evaluating repair requirements for damaged structures.

These services may include evaluating code upgrade requirements for building repairs or developing repair drawings and specifications for permitting.


Destructive & Non-destructive Testing​ and Evaluation Services

Forensic investigations and material assessments often require partial destructive testing of engineered structural elements and/or building materials. Sampling materials for laboratory studies to determine their physical properties, chemical composition, and/or behavior under a specific load condition is an important aspect of YA’s comprehensive investigative approach.

Litigation Support and Expert Witness Testimony

YA has assembled a team of expert engineers and architects—most of whom have advanced degrees, are licensed in multiple states, and have at least 15 to 20 years of experience evaluating and repairing existing buildings and structures. Together, YA engineers and architects bring hundreds of years of experience evaluating building and structural systems of all types.

YA personnel are uniquely qualified to provide litigation support services on all projects, including major structural collapses, delay claims, construction defect claims, water leakage, damage from natural disasters, builder’s risk, and surety claims. With our roster of experienced professionals, background in litigation support and expert witness testimony, and our background in forensic analysis, clients can be assured that YA will assign the appropriate level of expertise to their projects.

YA services include:

  • Consulting and Litigation Support
  • Expert Testimony
  • Presentation at Mediations, Arbitrations, and Dispute Review Boards
  • Preparation of Exhibits
  • Structural Analysis
  • Building Code Review and Analysis

Structural Failure Analysis​

Forensic investigations frequently involve analysis of structural systems and materials that are historic, deteriorated, distressed, or not constructed in accordance with design drawings. Accurately analyzing these non-conventional systems requires careful assessment of material properties, restraints, and connections and detailed consideration of in-service loading.

Geotechnical Engineering​

Forensic investigations of subsurface (geotechnical/geological) incidents can be complex. Though certain damages may be viewed from the surface, the primary problem may sometimes reside in the subsurface. YA professionals are experienced in assessing damages to structures and their foundations resulting from subsurface conditions, including sinkhole activity, shrink/swell (expansive) clays, slope movement (landslides), collapsible soils, organic soils, hydro-fracking, and mining or landfill activity.

YA also performs geotechnical investigations of related fields such as hydrology (surface water/erosion) and geohydrology (groundwater).

Our phased and multidisciplinary approach to the investigation of ground movement, damages, and subsurface conditions provides an efficient means to determine the cause as well as a cost-efficient method of remediation and repair.

YA services include:

  • Litigation Support and Testimony
  • Construction Defect and Builders Risk Evaluations
  • Earth Movement Investigations
  • Geotechnical and Geological Subsurface Investigations
  • Sinkhole and Subsidence Investigations
  • Soil Remediation Recommendations and Design
  • Geophysical Surveys
  • Monitoring of Compaction and Chemical Grouting Programs
  • Environmental Assessments
  • Soils, Groundwater and Landfill Gas Contamination Investigations

Materials Analysis & Lab Testing​

MEPF Failure Investigation

YA mechanical engineers have extensive experience assessing and troubleshooting distressed HVAC, refrigeration, plumbing, and fire protection systems. Our services also include evaluating industry standards and local and national building code requirements.

Whether evaluating effects from singular events such as fire, hail, or wind or evaluating effects from installation defects, lack of maintenance or wear and tear, YA engineers can diagnose the cause and extent of distress and provide recommendations for repairs.



Forensic meteorology is the scientific study of weather applied to reconstructing weather events for a certain time and location. This is done by acquiring and analyzing local weather reports such as surface observations, radar and satellite images, other data, and eyewitness accounts.  Forensic meteorology is often used in court cases, including insurance disputes, personal injury, and murder investigations. This is often the case when weather conditions are a possible factor, such as fall downs after snow and ice, wind, flooding, aviation, and nautical accidents. With increasing losses from severe weather in recent years, the demand for forensic meteorological services has also grown.

Marine Structures

Marine structures are a critical part of the global infrastructure. Harsh environments and extreme loads frequently cause damage and accelerated deterioration, even in properly designed marine structures. Some design approaches result in limited redundancy and tolerance for deterioration and damage of marine structures. Evaluation of these structures requires specialized knowledge of marine environments, corrosion, concrete deterioration, and wood decay, as well as marine design standards, modeling techniques, wind and wave action, and marine construction practices.

YA engineers have extensive experience evaluating marine structures, including piers, wharves, seawalls, floating docks, building platforms, and wave attenuators. Investigation techniques range from visual assessment to destructive and non-destructive testing of components. Structural evaluation often requires analytical modeling of extreme events such as seismic, wind, wave action, and ordinary service loading, including the weight of supported components, flotation, and soil-structure interaction. YA design and construction experience, coupled with a forensic background, provides clients with a unique resource in the marine engineering industry.

YA services include:

  • Damage Assessment
  • Destructive and Non-Destructive Testing
  • Structural Analysis
  • Finite Element Modeling
  • Development of Repair Drawings
  • Evaluation of Marine Code Requirements

Seismic Engineering​ & Risk Assessment

The exact nature of the next seismic event is unknown and cannot be predicted. Seismic engineers assess the existing built environment and guide the preparation for the next event using lessons learned from past events. The main goal of seismic engineering is to keep our communities safe. Our expertise lies in education and application to your buildings and properties.

We provide transparent seismic risk assessments that educate our clients on the current state of their structures and any vintage seismic detailing that may be present. If needed, we can assist with remediation measures, such as design or feasibility studies.

We aim to help our clients prepare for not if but when.


Slip & Fall / Premises Liability​

In premises liability cases, there is an allegation that a person was harmed due to conditions existing on another party’s property. Assertions of liability may be aimed at the property owner, manager, tenant, builder, or other related parties. The duty of care owed by these defendants may depend upon whether the claimant/plaintiff is an “invitee”, a “licensee”, or a “trespasser”. Premises liability case types often include pedestrian falls, walkway and bathing surface slips, trip events, stairway falls, and falls from elevation. These cases frequently involve complex intersections between scene features, active and legacy building codes, safety and health standards, and human factors and biomechanics – and may require specialized testing methods. YA consultants are available to assist on-premises liability cases. They are experienced testifying experts, nationally recognized leaders in slip resistance and friction analysis research, and actively involved in developing the industry standards underlying these analyses.

Premises liability services

  • Inspect, scan, and survey incident scenes
  • Analyze case images and security video
  • Conduct walkway and footwear friction analyses
  • Evaluate incident reports, testimony, and medical records
  • Analyze active and legacy codes, regulations and ordinances
  • Evaluate construction, alteration, and maintenance records
  • Create 3D visualizations for reports and legal exhibits