Dear All, I am trying to simulate a tent pavillion, but I had difficulties defining a thin tent material as Wall component. Giving 1 or 2 mm is not accepted by TRNSYS, anyone has an experience with it? or should I define a massless layer. Regards -- Ümit Esiyok e-mails: umitesiyok at gmx.de umit.esiyok at uni-dortmund.de