diff --git a/image_creator/disk.py b/image_creator/disk.py
index b84de1ac7c9a0bd2b75dd46f9e1212d5da8e5d57..7fc0cdfdc3765042694c2a893df702a75382098a 100644
--- a/image_creator/disk.py
+++ b/image_creator/disk.py
@@ -300,6 +300,6 @@ class DiskDevice(object):
         dev = self.g.part_to_dev(self.root)
         last = self.g.part_list(dev)[-1]
 
-        return last['part_end']
+        return last['part_end'] + 1
 
 # vim: set sta sts=4 shiftwidth=4 sw=4 et ai :