diff --git a/tools/builder_defaults.sh b/tools/builder_defaults.sh
index 2f58a7a3e4..2dc9e53144 100644
--- a/tools/builder_defaults.sh
+++ b/tools/builder_defaults.sh
@@ -197,7 +197,7 @@ export STAGE_CHROOT_DIR=${STAGE_CHROOT_DIR:-"${SCRATCHDIR}/stage-dir"}
 export FINAL_CHROOT_DIR=${FINAL_CHROOT_DIR:-"${SCRATCHDIR}/final-dir"}
 
 # 400M is not enough for amd64
-export MEMORYDISK_SIZE=${MEMORYDISK_SIZE:-"768M"}
+export MEMORYDISK_SIZE=${MEMORYDISK_SIZE:-"1024M"}
 
 # OVF/vmdk parms
 # Name of ovf file included inside OVA archive