About
Passionate Pursuit of Perfection
PEG, LLC is a leading consulting firm specializing in energy efficiency, engineering, environmental and management solutions. We deliver high-quality, sustainable construction services at competitive prices, helping clients across the U.S. improve building performance, reduce environmental impact, and achieve long-term cost savings.
We are more than problem-solvers—we are partners in progress. We assist builders and developers in meeting energy efficiency standards, designing sustainable, high-performance systems that improve building quality, reduce operational costs and meet regulatory requirements for energy use and sustainability. Our mission is to help clients achieve long-term cost savings while advancing energy efficiency and sustainability in the built environment.
As a woman-owned business, we are committed to creating opportunities for all. We actively support charitable organizations, provide training and education for our industry and maintain a valued network of subcontractors. Above all, we are dedicated to fostering personal and professional growth for every PEG associate.
Headquartered in Fairfax, Virginia, our team operates across time zones and industries, serving clients in sectors ranging from commercial and residential construction to institutional and governmental projects.
Together, we’re building a future that’s sustainable, efficient, and innovative!
What Sets Us Apart
A Virginia-Based Woman-Owned Small Business.
The only energy rating company with a 100% HERS energy rater inspection staff.
Licensed MEP engineering designers in all 50 states.
Extensive experience working with state and local agencies in the Eastern and Central U.S.
Expertise in providing tailored solutions to:
- Enhance energy performance
- Reduce costs
- Ensure compliance with building codes
Our success stems from a “team first” mentality, fostering collaboration through open communication, transparency and a supportive work environment that values work-life balance and professional growth. We nurture passion, diversity and drive by recognizing each team member’s unique contributions. With a people-centered culture, expertise and innovation, we are committed to advancing sustainability and shaping a greener future for the construction industry and the communities we serve.
Our History
PEG, LLC traces its roots back to 1998 when it was founded as Patuxent Environmental Group, Inc. by Matthew Cooper, who served as the company’s first President. Drawing on his extensive expertise in mechanical engineering and environmental systems from his time at the Trane Corporation and GSA property management, Mr. Cooper identified a unique opportunity to combine these skills to address challenges in building performance and diagnostics.
In its early years, Patuxent Environmental Group focused on indoor air quality and building performance consulting, working on complex projects for federal GSA properties, military institutions and major commercial and institutional sites. PEG quickly gained a reputation for its pragmatic approach to solving complicated built-environment failures, including those involving hotels, hospitals, multi-family buildings and single-family communities. The firm’s willingness to take on challenging projects often avoided by others made it a trusted partner for law practices litigating built-environment cases.
In 2005, JoAnn Spence joined the firm, bringing over a decade of experience in the production homebuilding industry, including her leadership roles at Centex Homes, a Fortune 500 construction firm. Her expertise spanned finance, construction, warranty and customer satisfaction, and her influence introduced a new level of professionalism, customer service and operational growth to PEG.
In 2014, the firm transitioned to PEG, LLC, with Ms. Spence acquiring majority ownership and stepping into the role of President & CEO. Mr. Cooper took on the role of minority owner, serving as Senior Vice-President & COO. Together, their leadership has continued to guide PEG in delivering innovative solutions in energy efficiency, engineering and sustainability, solidifying the company as a leader in the built environment consulting industry.