diff --git a/ProcessLib/CMakeLists.txt b/ProcessLib/CMakeLists.txt
index 90f13ae0c4905a596b385510a42e696443c01ca7..f62acb58fa1eadd749b2c78e85ec83291296303e 100644
--- a/ProcessLib/CMakeLists.txt
+++ b/ProcessLib/CMakeLists.txt
@@ -22,6 +22,9 @@ APPEND_SOURCE_FILES(SOURCES TES)
 add_subdirectory(HeatConduction)
 APPEND_SOURCE_FILES(SOURCES HeatConduction)
 
+add_subdirectory(CalculateSurfaceFlux)
+APPEND_SOURCE_FILES(SOURCES CalculateSurfaceFlux)
+
 APPEND_SOURCE_FILES(SOURCES Utils)
 
 add_library(ProcessLib ${SOURCES})