Twining’s legacy dates back more than 125 years. What started as a family business in 1898 has evolved into one of California’s largest service providers of multi-disciplinary engineering services. Highly regarded by owners, developers, contractors, consultants, and the industry for providing high-quality services that are reliable, timely, and compliant, Twining has been a central part of some of California’s most regionally significant construction projects. We employ some of the industry’s most well-known construction experts who perform research as well as consult with regulatory agencies to shape the future of construction standard practices.

Twining is a full-service engineering company with unmatched technical expertise. As detailed below, our services span from QA/QC, materials testing, and inspection to highly technical capabilities in applied engineering and integrated disciplines. With laboratories throughout California and a deep bench of engineers, technical experts, materials scientists, technicians, and inspectors, we are unequaled in our core competencies to serve the built environment:

• Geotechnical Engineering
• Asphalt Pavement Quality Assurance Services
• Asphalt Pavement Design and Materials Evaluations
• Soils and Materials Testing and Inspection
• Specialty Testing
• Mobile Laboratory Services
• Roofing and Waterproofing Consultation and Inspection
• Applied Engineering and Research
• Forensic Evaluation
• Concrete Engineering and Materials Science
• Stormwater Management
• Geo-Instrumentation Monitoring and Assessment
• Third-Party Product Testing
• Plan Approvals and Inspection
• Petrography