As an employee-owned enterprise of builders, we serve as a foundation and center of excellence for our companies to learn, expand, and propel themselves into the future. Defined by authenticity and transparency, we celebrate our people, their local knowledge, dedication to craftsmanship and safety, and the strong relationships they have with their communities.
The STO Building Group family of companies — Structure Tone, Structure Tone Southwest, Structure Tone International, Pavarini North East Construction, Pavarini McGovern, LF Driscoll, LF Driscoll Healthcare, Govan Brown, Ajax Building Company, BCCI Construction, Layton Construction, Abbott Construction, and RC Andersen — includes over 4,000 employees located in offices throughout the US, Canada, UK, and Ireland. We provide a complete range of services, from site selection analysis, design constructability review and aesthetic enhancements to interior fit-outs, new building construction, and building infrastructure upgrades and modernizations.
Top 20 Contractor by Engineering News-Record
$2.5 Billion in bonding capacity
Experts in projects from 1,000 to 1.5 million+ sf
45 offices across US, Canada, UK & Ireland
$8 Billion in annual construction volume
Founded and headquartered in New York City in 1971, Structure Tone is one of the leading full-service construction management companies in New York, Boston, New Jersey and Philadelphia.
Founded in 1977, Texas-based Constructors & Associates joined the STO Building Group in the 1980s, shifting to the name Structure Tone Southwest in 2010.
Established in 1988, Structure Tone International is a leading construction service provider specialising in high-quality fit-out, refurbishment and mission critical projects through offices in Ireland and the UK.
For over 125 years, Pavarini has been meeting the construction needs of new and interior corporate commercial, higher education and healthcare clients across Connecticut and surrounding communities.
Founded as part of the Structure Tone organization in 2001, Pavarini McGovern is a construction management and general contracting firm, focusing on the construction of new buildings and major expansions in a variety of market sectors.
LF Driscoll, headquartered in Philadelphia, joined STO Building Group in 2009 and is one of the region’s top builders. Founded in 1929, the firm specializes in commercial construction with a strong emphasis on healthcare, cultural and higher education market sectors.
LF Driscoll Healthcare provides a full range of construction management and general contracting services for nearly every type and scale of healthcare project.
Govan Brown, headquartered in Toronto, Canada, specializes in commercial interiors for the corporate, retail and hospitality markets. Since 1994, Govan Brown has completed thousands of projects for clients across Canada.
Based in the southeastern US, Ajax is one of the fastest growing construction companies in the region. Founded in 1958, Ajax specializes in renovations and new construction for the educational, municipal, healthcare and cultural sectors.
Founded in 1986, BCCI Construction is a leading West Coast builder with offices in San Francisco, Silicon Valley, and Los Angeles. BCCI provides clients with a comprehensive building experience from concept to completion.
Founded in 1953, Layton is a nationally-ranked commercial contractor with proven experience in virtually every industry, including healthcare, retail, hospitality, manufacturing, distribution, education, office, industrial, detention, tenant improvement and public facilities.
Founded in 1983, Abbott is a US West Coast commercial builder known for superior planning and execution—serving a variety of sectors such as healthcare, hospitality, education, nonprofit, retail, and tenant interiors.