Ilka Cassidy, Dipl. Ing. Architecture, CPHC, Co-founder of Holzraum System, is passionate about Passive House envelope design and building science, focusing on the benefits of natural building materials. She grew up in Germany and received her Diploma of Engineering/ Architecture degree from the RWTH Aachen. Ilka connected to the US during her year at the University of Washington in Seattle where she won a Scholarship to study within the graduate program. Eventually she moved to Philadelphia where she co-founded C2 Architecture in 2005. She has worked on multiple projects as a Certified Passive House Consultant and is an active member of Green Building United in Philadelphia.