
Edgewater and Duchossois partnered with industry executive Brandon Ost in 2017 to form Air Filtration Holdings as a platform to acquire companies that manufacture air filtration products used in commercial and industrial systems. Now, in partnership with Audax, Rensa will continue its strategy to acquire filtration product suppliers. Mr. Ost and other members of the company’s senior management team will continue to lead the company and will maintain a significant equity ownership position.
Since 2017, Rensa has acquired Viskon-Aire, a Maryland-headquartered manufacturer of air and paint filtration products used in commercial and industrial HVAC and paint spray booth applications (July 2017); Permatron, an Illinois-based manufacturer of air filter components (September 2017); RoboVent, a Michigan-based maker of air filtration equipment and systems used in welding, cutting and metalworking applications (February 2018); D-Mark, a Michigan-based manufacturer of molecular filtration products (October 2018); Air Filters, Inc., a Texas-based full-line filtration products manufacturer (October 2018); and Custom Filter, an Illinois-based maker of HEPA and ULPA filters (August 2021).
Today, Rensa Filtration has facilities in Maryland, Illinois, Michigan, and Texas, and goes to market under six company-owned brands including Rensa, Custom Filter, Viskon-Aire, Permatron, D Mark, and Air Filters, Inc.

“Since our founding, Rensa has honored its commitment to engineering excellence, continuous improvement, and innovation—and Audax’s investment is a critical piece of our overall strategy as we continue to build a world-class filtration business,” said Mr. Ost. “We believe Rensa has never been better positioned for growth and look forward to benefiting from Audax’s proven expertise and value-add resources.”

Audax invests in middle-market companies that have from $8 million to $50 million in EBITDA and enterprise values of $50 million to $400 million. Sectors of interest include business and consumer services; energy; healthcare; technology, media and telecom; and industrials including chemicals, infrastructure, and building materials. Audax, with offices in Boston, New York, and San Francisco, is currently investing out of its $3.5 billion, sixth private equity fund.
Lincoln International was the financial advisor to Audax and Baird was the financial advisor to Rensa.
© 2022 Private Equity Professional | August 18, 2022



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