diff --git a/overcloud.j2.yaml b/overcloud.j2.yaml
index d788d3d66a..df01facaa8 100644
--- a/overcloud.j2.yaml
+++ b/overcloud.j2.yaml
@@ -979,7 +979,7 @@ resources:
         {{network.name_lower}}_host_routes:
           list_concat_unique:
             - {get_attr: [Networks, net_attributes_map, {{network.name_lower}}, subnets, {{_role_net_subnet}}, host_routes]}
-          {%- if network.name in role.default_route_networks %}
+          {%- if role.default_route_networks is defined and network.name in role.default_route_networks %}
             - - default: true
                 next_hop: {get_attr: [Networks, net_attributes_map, {{network.name_lower}}, subnets, {{_role_net_subnet}}, gateway_ip]}
           {%- endif %}
@@ -1019,7 +1019,7 @@ resources:
         service_metadata_settings: {get_attr: [{{role.name}}ServiceChainRoleData, value, service_metadata_settings]}
         tripleo_network_config_template: {get_param: {{role.name}}NetworkConfigTemplate}
         tripleo_network_config_with_ansible: {get_param: NetworkConfigWithAnsible}
-        default_route_networks: {{role.default_route_networks}}
+        default_route_networks: {{role.default_route_networks|default(['ControlPlane'])}}
         networks_skip_config: {{ role.networks_skip_config|default([]) }}
         role_tags: {{role.tags}}
 
@@ -1052,7 +1052,7 @@ resources:
       {{network.name}}InterfaceRoutes:
         list_concat_unique:
           - {get_attr: [Networks, net_attributes_map, {{network.name_lower}}, subnets, {{_role_net_subnet}}, host_routes]}
-        {%- if network.name in role.default_route_networks %}
+        {%- if role.default_route_networks is defined and network.name in role.default_route_networks %}
           - - default: true
               next_hop: {get_attr: [Networks, net_attributes_map, {{network.name_lower}}, subnets, {{_role_net_subnet}}, gateway_ip]}
         {%- endif %}
@@ -1064,7 +1064,7 @@ resources:
                    not $.data.where($.startsWith('tripleo_vlan_id')).len() => 1,
                    true => int($.data.where($.startsWith('tripleo_vlan_id')).first().split('=').last()))
           data: {get_attr: [Networks, net_attributes_map, {{network.name_lower}}, subnets, {{_role_net_subnet}}, tags]}
-    {%- if network.name in role.default_route_networks %}
+    {%- if role.default_route_networks is defined and network.name in role.default_route_networks %}
       {{network.name}}InterfaceDefaultRoute: {get_attr: [Networks, net_attributes_map, {{network.name_lower}}, subnets, {{_role_net_subnet}}, gateway_ip]}
     {%- endif %}
   {%- endfor %}