diff --git a/bot/build.sh b/bot/build.sh
index 223891117d..6bf7827d66 100755
--- a/bot/build.sh
+++ b/bot/build.sh
@@ -296,6 +296,10 @@ if [[ ! -z ${SHARED_FS_PATH} ]]; then
     BUILD_STEP_ARGS+=("--host-injections" "${SHARED_FS_PATH}/host-injections")
 fi
 
+if [[ ! -z ${LOWER_DIRS} ]]; then
+    BUILD_STEP_ARGS+=("--lower-dirs" "${LOWER_DIRS}")
+fi
+
 # create tmp file for output of build step
 build_outerr=$(mktemp build.outerr.XXXX)