Thornton Tomasetti

About Thornton Tomasetti

Thornton Tomasetti is an international engineering firm founded in 1949 and headquartered at 120 Broadway in New York City. Employee-owned and privately held, it employs more than 1,500 people across over 50 offices in North America, the United Kingdom, the Middle East and Asia-Pacific, and has delivered projects in more than 50 countries.

The firm's stated purpose is optimising the design and performance of structures, materials and systems for projects of every size and level of complexity - a scope that spans the entire life cycle of a building, from early concept through construction, occupation, adaptation and, when necessary, investigation after failure.

Practice Areas

Building Structure

The practice on which the firm's reputation was built. Thornton Tomasetti has engineered many of the world's tallest and most structurally demanding buildings, alongside stadiums, transport hubs, cultural venues and complex commercial developments.

Building Skin

Facade engineering covering curtain wall design, cladding systems, glazing performance, weatherproofing and the thermal and structural behaviour of the building envelope - increasingly the most technically demanding element of a modern building.

Building Performance

Analysis of how a completed building actually behaves: energy modelling, daylighting, thermal comfort, acoustics and computational simulation used to test design decisions before they are built.

Construction Support Services

Assistance during delivery, including constructibility review, connection design, temporary works, erection engineering and support for contractors managing complex structural sequences on site.

Property Loss Consulting

Forensic engineering and failure investigation - determining why structures fail, supporting insurance and legal proceedings, and advising on repair and reinstatement. Few firms combine original design capability with forensic expertise at this scale, and each discipline informs the other.

Sustainability

Embodied carbon assessment, low-carbon structural design, material efficiency, resilience planning and certification support. Structural engineering carries a disproportionate share of a building's embodied carbon, which puts this practice at the centre of meaningful decarbonisation.

Technology and Research

Thornton Tomasetti has been unusually active in developing its own computational tools, with an in-house research and applied technology group producing software for structural optimisation, parametric design and data-driven engineering. Several of these tools have been released to the wider AEC community rather than kept proprietary.

Sectors Served

• Tall buildings and high-rise commercial development
• Sports venues and stadiums
• Aviation and transportation infrastructure
• Healthcare and science facilities
• Higher education and cultural buildings
• Residential and mixed-use development
• Industrial and energy structures
• Historic renovation and adaptive reuse

Market Position

Thornton Tomasetti sits among the most recognised structural engineering consultancies globally, particularly for technically ambitious projects where conventional solutions do not apply. Its own tagline captures the positioning directly: when others say no, the firm says here's how. Employee ownership gives it a degree of independence in how it invests in research and long-term capability that publicly traded competitors do not always have.

Working With Thornton Tomasetti

Typical clients include architects, developers, contractors, institutions, government agencies and insurers. For architects pursuing structurally complex forms, and for owners dealing with facade performance or building failure, the firm is one of the principal engineering consultancies to know across the global AEC industry.