diff --git a/playbooks/install.py b/playbooks/install.py
index 657cf465..e61dd298 100755
--- a/playbooks/install.py
+++ b/playbooks/install.py
@@ -335,6 +335,9 @@ def parse_commandline_args():
 	parser.add_argument('--without-bench-setup', dest='without_bench_setup', action='store_true', default=False,
 		help=argparse.SUPPRESS)
 
+	# whether to overwrite an existing bench
+	parser.add_argument('--overwrite', dest='overwrite', action='store_true', default=False)
+
 	args = parser.parse_args()
 
 	return args