Executive Leaders

Gunner Smith began serving as Chief Executive Officer for Cornerstone Building Brands on Aug. 11, 2025.

Prior to joining Cornerstone Building Brands, Mr. Smith served as president of Roofing at Owens Corning, an $11 billion leading building products manufacturer, a position he held since 2018. In this role, he had responsibility for a market-leading roofing business in the United States and Canada focused primarily on roofing shingles and components that go to market through distributors, home centers and lumberyards, as well as the global nonwovens fabric business. He also served as vice president of sales, distribution and home centers and in other positions leading sales, marketing and pricing roles during his 17-year tenure with Owens Corning. Prior to joining Owens Corning, Mr. Smith served as National Sales Manager at PlyGem®, now part of Cornerstone Building Brands.  Earlier in his career, he served in sales management roles for eight years at Elk Corporation. He has a strong track record of delivering growth, executing strategy and building trusted customer relationships in the building products industry.

Mr. Smith holds a bachelor’s degree in business administration from Mississippi State University and completed the Executive Program in Strategic Sales Management at the University of Chicago’s Booth School of Business.

Michael Pulcanio began serving as Chief Human Resources Officer for Cornerstone Building Brands on May 18, 2026.

A seasoned human resources leader, Mr. Pulcanio is known for his strategic approach to talent development, organizational culture and building high-performing teams. He has more than two decades of progressive HR leadership experience in highly complex manufacturing environments, with a strong track record of driving organizational excellence and operational efficiency.

Throughout his career, Mr. Pulcanio has closely partnered with commercial, operations and functional leaders to enable business transformation and deliver results. His expertise spans executive succession, leadership development, culture transformation, labor strategy, post-merger integration and HR technology modernization.

Prior to joining Cornerstone Building Brands, Mr. Pulcanio served as Executive Vice President and Chief Human Resources Officer at CJ Schwan’s Co., where he led enterprise-wide human capital strategy. Earlier, he spent nine years at Tyson Foods, serving in senior HR leadership roles supporting global operations and commercial organizations, including as the HR partner to the Chief Customer Officer and international leadership team. He also held leadership roles at Hillshire Brands, Aon and PepsiAmericas.

Mr. Pulcanio received a bachelor’s degree in business from Northern Illinois University and a law degree from John Marshall Law School. Prior to pursuing a career in HR, he served as a labor attorney.

Austin So began serving as Executive Vice President, General Counsel and Corporate Secretary for Cornerstone Building Brands on July 13, 2026.

An accomplished legal and executive leader, Mr. So is known for aligning legal strategy with business priorities to support growth, strengthen governance and create long-term value. He brings nearly 25 years of broad legal and enterprise leadership experience, including 14 years as General Counsel across publicly traded, private equity-controlled and global organizations.

Throughout his career, Mr. So has guided companies through business transformation, complex governance matters, risk management, government relations, sustainability initiatives and periods of significant organizational change. His leadership experience spans manufacturing, building products, global industrial businesses and multi-site service organizations.

Prior to joining Cornerstone Building Brands, Mr. So served as Senior Vice President, General Counsel, Head of Government Relations and Chief Sustainability Officer at Armstrong World Industries, where he helped align legal, government relations and sustainability initiatives with the company’s growth strategy. Previously, he served as Senior Vice President, Chief Legal Officer and Secretary at StoneMor Inc., and was Division General Counsel and Secretary for Heraeus Holding GmbH.

Mr. So began his legal career in private practice with leading law firms, including Cravath, Swaine & Moore LLP. He received a bachelor’s degree in government from Harvard University and a Juris Doctor from the University of Pennsylvania Law School.

Matthew Garth began serving as Chief Financial Officer for Cornerstone Building Brands on Sept. 14, 2026.

With more than three decades of executive leadership experience, Mr. Garth has a proven track record of improving financial performance, driving operational excellence and leading transformational change across publicly traded companies and complex organizations. He is recognized for his ability to align strategy, operations and finance to create long-term value and support sustainable growth.

Prior to joining Cornerstone Building Brands, Mr. Garth served as Executive Vice President and Chief Financial Officer of Dentsply Sirona, a leading dental products and technologies company. In that role, he led the company’s global finance organization and helped advance strategic initiatives, operational performance and value creation. Previously, he served as Executive Vice President, Chief Financial Officer and Chief Administrative Officer at The Scotts Miracle-Gro Company, where he played a key role in strengthening financial performance, supporting business stabilization efforts and advancing strategic planning initiatives. Earlier in his career, Matt was CFO at Minerals Technologies and held senior finance leadership roles at Alcoa.

In addition to leading finance organizations, Mr. Garth has extensive experience overseeing information technology functions and leveraging digital capabilities to support business objectives. Known for his collaborative leadership style, he has successfully guided organizations through change while building high-performing teams and delivering results.

Mr. Garth earned a bachelor’s degree in accounting from the University of Delaware and an MBA from Columbia University.

Lisa Domnisch joined Cornerstone Building Brands as President of our Canadian Business Unit in August 2023. Ms. Domnisch brings nearly 20 years of strategic leadership experience in product development, business planning, sales and marketing, and operational excellence to Cornerstone Building Brands, serving most recently as Global Product Leader for DuPont’s Water & Protection construction business. Prior to this role, Ms. Domnisch held various leadership roles of increasing responsibility at DuPont and built a successful consulting practice accelerating results, building capability and aligning diverse stakeholders in the agriculture and not-for-profit sectors.

Ms. Domnisch studied political science at the University of Western Ontario and received an Honors of Business Administration diploma from the Canadian Institute of Business. A lifelong learner, she has completed Executive Leadership programs from the Columbia Graduate School of Business, MIT Sloan School of Management and the University of Guelph.

Matthew Ackley joined Cornerstone Building Brands as President, Engineered Building Systems on April 12, 2021, was promoted to President, Metal Solutions effective November 11, 2021, and now serves as CEO of Fortify Building Solutions.

He brings with him nearly 20 years of accomplished leadership in the building materials industry. Most recently, Mr. Ackley served as Vice President, Sales for USG Corporation, overseeing its Commercial Ceilings and Corporate Accounts teams, where he led strategic planning, sales execution and revenue and profit growth efforts.

Mr. Ackley spent much of his career at USG Corporation, holding roles of increasing responsibility including: Vice President, Architectural Sales; Area Manager, Central; Sr. Manager, Investor Relations; Category Manager, Interior Walls – L&W Supply and several other roles in sales and operations. He holds a B.A. in Economics and Spanish from University of Redlands and an MBA from Pepperdine University.

Melissa Jones serves as President, Siding & Accessories, having joined Cornerstone Building Brands in July 2022.

Ms. Jones brings more than 20 years of leadership experience and demonstrated success delivering revenue and profit growth through customer-centric organic growth strategies, M&A integration, operational excellence, and commercial excellence in the industrial machinery and electrical manufacturing industries. Most recently, Ms. Jones served as Group President, Commercial Water Solutions at Pentair, a global water treatment and solutions company, where she also held other various roles of increasing responsibility.

Prior to Pentair, Ms. Jones was Director of Product, Channel and Marketing at Generac Power Systems and Director of Marketing at Johnson Controls. She has also worked in corporate marketing functions at Abbott Laboratories, Milwaukee Tool and Stanley Black & Decker.

Ms. Jones holds a Bachelor of Arts in economics from St. Mary’s Honors College of Maryland and an M.B.A from the University of Maryland.

Vishal Singh began serving as President of Windows & Doors for Cornerstone Building Brands on Jan. 19, 2026.

A seasoned business leader, Mr. Singh is known for his results orientation, continuous improvement mindset and focus on building high-performing teams. He has more than two decades of leadership experience in the building products industry and a strong track record of driving growth, operational excellence and digital transformation.

Prior to joining Cornerstone Building Brands, Mr. Singh served as President of BrassCraft, a Masco Corporation company, where he led its global manufacturing and distribution business for rough plumbing products. Prior to BrassCraft, he was President of Architectural Glass at Oldcastle Building Envelope, overseeing a business operating 27 manufacturing facilities. He also served as President of Milgard Windows at Masco, where he strengthened customer relationships across dealers, home centers and builders. Earlier in his career, he spent 14 years with Eaton Corporation, where had roles of increasing responsibility, ultimately serving as VP and GM of its Transportation, Military and Aerospace Division.

Mr. Singh holds a bachelor’s degree in mechanical engineering from Sardar Patel University in India and earned his MBA from Case Western Reserve University.

Susan S. Selle has served as Chief Marketing Officer for Cornerstone Building Brands since November 2018. Before the formation of Cornerstone Building Brands, Ms. Selle served as Chief Marketing Officer for Ply Gem since July 2014.

Before joining Ply Gem, Ms. Selle held senior marketing and brand leadership roles with Jarden Consumer Solutions (formerly Sunbeam Products) from 1998 – 2014. While at Jarden, she led global marketing, customer marketing, advertising strategy, category management, digital & social marketing, shopper marketing and portfolio brand management for leading brands such as Mr. Coffee, Crock-Pot, Oster, Sunbeam, Foodsaver, First Alert, Holmes, Margaritaville Products and Healthometer. Prior to joining Jarden, Ms. Selle was employed by Tyson Foods in Retail Product Marketing and Nestle Foods in Sales and Regional Marketing.

Ms. Selle graduated from University of Missouri – Columbia with B.S in Marketing and Management and brings over 30 years of marketing experience with top Fortune 500 companies.