diff --git a/src/ifcgeom/ConversionSettings.h b/src/ifcgeom/ConversionSettings.h
index d09ed50b5d..77b77193ce 100644
--- a/src/ifcgeom/ConversionSettings.h
+++ b/src/ifcgeom/ConversionSettings.h
@@ -3,6 +3,7 @@
 
 #include <array>
 #include <limits>
+#include <string>
 
 #include "ifc_geom_api.h"