Journal of Living Architecture (2014) 1(4) 1 Substrate loss is minimal in vegetated and un-vegetated extensive roof modules over a 14-month period Kirk D. Laminack 1 , Bruce D. Dvorak 2 and Astrid Volder 3 1 Green Roof Specialist, Moore Farms Botanical Garden, Lake City, SC, kirkdl9@yahoo.com 2 Assistant Professor, Texas A&M University, College Station, TX, bdvorak@tamu.edu 3 Associate Professor, University of California, Davis, CA, avolder@ucdavis.edu Laminack, K.D., Dvorak, B.D. & Volder, A., 2014. Substrate loss is minimal in vegetated and un- vegetated extensive roof modules over a 14-month period. Journal of Living Architecture. 1(4):1- 13.