diff --git a/environments/undercloud.yaml b/environments/undercloud.yaml
index 9563e0440e..82af21986a 100644
--- a/environments/undercloud.yaml
+++ b/environments/undercloud.yaml
@@ -132,3 +132,5 @@ parameter_defaults:
   MistralDockerGroup: true
   PasswordAuthentication: 'yes'
   ContainerImagePrepareLogFile: ../install-undercloud.log
+  HeatEngineOptVolumes:
+    - /usr/lib/heat:/usr/lib/heat:ro