diff --git a/ProcessLib/LIE/Common/Utils.cpp b/ProcessLib/LIE/Common/Utils.cpp
index 905c26cf8f472f6d31defa3a081b4a6b5b2b967f..b345f028d4b20370181381506360ed61387b6292 100644
--- a/ProcessLib/LIE/Common/Utils.cpp
+++ b/ProcessLib/LIE/Common/Utils.cpp
@@ -28,6 +28,7 @@ void computeNormalVector(MeshLib::Element const& e, unsigned const global_dim,
         auto v1 = (*e.getNode(1)) - (*e.getNode(0));
         element_normal[0] = -v1[1];
         element_normal[1] = v1[0];
+        element_normal[2] = 0;  // not used in 2d but needed for normalization
         element_normal.normalize();
     }
     else if (global_dim == 3)