diff --git a/src/BarrelCalorimeter_geo.cpp b/src/BarrelCalorimeter_geo.cpp
index 0e028bcb4b90ad52f94a1a18bb60f7f264802a8e..704594131c4eed80e05af643e459788afbdf5937 100644
--- a/src/BarrelCalorimeter_geo.cpp
+++ b/src/BarrelCalorimeter_geo.cpp
@@ -56,7 +56,7 @@ static Ref_t create_detector(Detector& description, xml_h e, SensitiveDetector s
   double dx = 0.0; //mod_z / std::sin(dphi); // dx per layer
 
   // Compute the top and bottom face measurements.
-  double trd_x2 = (2 * std::tan(hphi) * outer_r - dx- support_thickness)/2 - tolerance;
+  double trd_x2 = (2 * std::tan(hphi) * outer_r - dx)/2 - tolerance;
   double trd_x1 = (2 * std::tan(hphi) * inner_r + dx)/2 - tolerance;
   double trd_y1 = x_dim.z()/2 - tolerance;
   double trd_y2 = trd_y1;