diff --git a/tcp_tests/helpers/oslo_cfg_types.py b/tcp_tests/helpers/oslo_cfg_types.py
index 962f2d3..135798f 100644
--- a/tcp_tests/helpers/oslo_cfg_types.py
+++ b/tcp_tests/helpers/oslo_cfg_types.py
@@ -104,7 +104,10 @@
 
         env_var_name = args[0].upper()
         if 'default' in kwargs:
-            kwargs['default'] = os.environ.get(env_var_name, kwargs.get('default', None))
+            # Load a default environment variable with expected type
+            kwargs['default'] = args[1](
+                os.environ.get(env_var_name, kwargs.get('default', None))
+            )
         super(Cfg, self).__init__(*args, **kwargs)
 
         # Print info about default environment variables to console
diff --git a/tcp_tests/templates/ironic_standalone/underlay.yaml b/tcp_tests/templates/ironic_standalone/underlay.yaml
index ab9a9d2..6f54227 100644
--- a/tcp_tests/templates/ironic_standalone/underlay.yaml
+++ b/tcp_tests/templates/ironic_standalone/underlay.yaml
@@ -76,7 +76,7 @@
 
         nodes:
           - name: {{ HOSTNAME_IRONIC }}
-            role: salt_master
+            role: ironic_master
             params:
               vcpu: !os_env SLAVE_NODE_CPU, 2
               memory: !os_env SLAVE_NODE_MEMORY, 2048
diff --git a/tcp_tests/tests/environment/test_ironic_standalone.py b/tcp_tests/tests/environment/test_ironic_standalone.py
index 7d20c7c..8d60279 100644
--- a/tcp_tests/tests/environment/test_ironic_standalone.py
+++ b/tcp_tests/tests/environment/test_ironic_standalone.py
@@ -33,7 +33,7 @@
 
         Before using, please set the correct roles and timeout:
 
-            export ROLES=["ironic_master",]
+            export ROLES='["ironic_master"]'
             export BOOTSTRAP_TIMEOUT=900
 
         , and unset these variables after the bootstrap is completed.