diff --git a/builder/image-build-ros.sh b/builder/image-build-ros.sh
index 108cfe63..2b85b94a 100755
--- a/builder/image-build-ros.sh
+++ b/builder/image-build-ros.sh
@@ -18,7 +18,7 @@ set -ex # exit on error, echo commands
 
 ROS_DISTRO=noetic
 . /etc/os-release # set $VERSION_CODENAME to Debian release code name
-export ROS_OS_OVERRIDE=$VERSION_CODENAME
+export ROS_OS_OVERRIDE=debian:$VERSION_CODENAME
 
 echo "=== Building ROS from scratch"