diff --git a/Images/GNUmakefile.postamble b/Images/GNUmakefile.postamble
index cec9ac867..aa9f74608 100644
--- a/Images/GNUmakefile.postamble
+++ b/Images/GNUmakefile.postamble
@@ -41,10 +41,12 @@
 # Things to do after compiling
 # after-all::
 
-# Things to do before installing
-before-install::
+$(imagedir):
 	$(MKDIRS) $(imagedir)
 
+# Things to do before installing
+before-install:: $(imagedir)
+
 # Things to do after installing
 after-install::
 	for file in $(IMAGE_FILES); do \