• Performance. Integrity. Commitment.
    Performance. Integrity. Commitment.
  • Creating Experiences
    Creating Experiences
  • Building Partnerships for Life
    Building Partnerships for Life
  • Cultivating Relationships
    Cultivating Relationships
  • Tackling Challenges
    Tackling Challenges
  • Achieving Visions
    Achieving Visions

Who we are

For more than three decades, our construction team has built exceptional projects and durable industry partnerships in the metropolitan Washington, DC-Baltimore region—the kind that are forged from shared experiences and tempered by the bond of persisting through the hard times and the good times.

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What we do

We see things differently: We understand owner objectives and how to solve construction project challenges from concept to occupancy. Through this process, we build Partnerships for Life.

Pre-Construction

Pre-Construction

Before construction begins, TW is ready to work—collaborating with owners and stakeholders to develop cost-effective solutions and realistic construction timelines. 

General Contracting

General Contracting

TW Standards are high! We assemble experienced teams, realistic project schedules, maintain accurate cost controls and ensure effective lines communication throughout projects. 

Construction Management

Construction Management

Decades of industry experience give the TW team insight into owners’ expectations and the challenges associated with projects of all scales, across most sectors and through multiple project modes.

Design-Build

Design-Build

TW’s design-build process assures our clients their project will benefit from cost-saving alternatives, complete design coordination, and accelerated project delivery—all under a single contract.

Featured Projects

  • Hughes Network Systems teaser image
  • Crystal Rock Office Building  teaser image
  • Somerset Pool teaser image
  • DDG Offices teaser image
  • NIST Net Zero House  teaser image
  • Jared Jewelers  teaser image
  • Panera Bread teaser image

Our projects say it all. The right relationships build remarkable projects, and our business is building exceptional construction partnerships with owners, architects, property managers and subcontractors. Through our projects, we build Partnerships for Life.   

We have completed more than 600 projects, averaging approximately 60 per year, over 6 million square feet of space, and more than $300 million in construction value.              

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Therrien Waddell was one of the early adopters educating and practicing sustainable construction in the Washington, DC-Baltimore metro region. Our experience shows that our early involvement in new construction projects contributes to more effective, creative and sustainable results, fulfilling our commitment to cleaner and better communities.  

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News

What’s new? On the move and making a difference!

ABC Excellence In Construction Awards
Chamber Golf Sponsor
08 Sep

Chamber Golf Sponsor

TW was a Corporate Sponsor of the annual Gaithersburg-Germantown Chamber of Commerce Golf Classic at Worthington Manor Golf Club

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TW Annual Tail Gate Party