diff --git a/manifests/init.pp b/manifests/init.pp
index d4fd2db..edba7eb 100644
--- a/manifests/init.pp
+++ b/manifests/init.pp
@@ -20,18 +20,18 @@
 class nodepool (
   $mysql_root_password,
   $mysql_password,
-  $nodepool_ssh_private_key = '',
+  $nodepool_ssh_private_key,
   $git_source_repo = 'https://git.openstack.org/openstack-infra/nodepool',
   $revision = 'master',
-  $statsd_host = '',
+  $statsd_host = undef,
   $vhost_name = $::fqdn,
   $image_log_document_root = '/var/log/nodepool/image',
   $enable_image_log_via_http = false,
   $environment = {},
   # enable sudo for nodepool user. Useful for using dib with nodepool
   $sudo = true,
-  $scripts_dir = '',
-  $elements_dir = '',
+  $scripts_dir = undef,
+  $elements_dir = undef,
   $logging_conf_template = 'nodepool/nodepool.logging.conf.erb',
   $jenkins_masters = [],
 ) {
@@ -125,7 +125,7 @@ class nodepool (
     ensure => directory,
   }
 
-  if ($scripts_dir != '') {
+  if ($scripts_dir != undef) {
     file { '/etc/nodepool/scripts':
       ensure  => directory,
       owner   => 'root',
@@ -139,7 +139,7 @@ class nodepool (
     }
   }
 
-  if ($elements_dir != '') {
+  if ($elements_dir != undef) {
     file { '/etc/nodepool/elements':
       ensure  => directory,
       owner   => 'root',
diff --git a/templates/nodepool.default.erb b/templates/nodepool.default.erb
index 005053c..8dd69e3 100644
--- a/templates/nodepool.default.erb
+++ b/templates/nodepool.default.erb
@@ -1,4 +1,4 @@
-<% if @statsd_host != "" -%>
+<% if @statsd_host != nil && @statsd_host != "" -%>
 export STATSD_HOST=<%= @statsd_host %>
 export STATSD_PORT=8125
 <% end -%>