Twining’s legacy dates back more than 120 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 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
• Stormwater management
• Geo-instrumentation monitoring and assessment
• Third Party Product Testing
• Plan Approvals and Inspection
• Petrography