diff -u b/core/includes/bootstrap.inc b/core/includes/bootstrap.inc
--- b/core/includes/bootstrap.inc
+++ b/core/includes/bootstrap.inc
@@ -491,11 +491,11 @@
   }
   elseif (!empty($config_directories[$type])) {
     // Allow a configuration directory path to be outside of webroot.
-    if ($config_directories[$type]['absolute']) {
-      $path = $config_directories[$type]['path'];
+    if (empty($config_directories[$type]['absolute'])) {
+      $path = conf_path() . '/files/' . $config_directories[$type]['path'];
     }
     else {
-      $path = conf_path() . '/files/' . $config_directories[$type]['path'];
+      $path = $config_directories[$type]['path'];
     }
   }
   else {
diff -u b/core/includes/install.inc b/core/includes/install.inc
--- b/core/includes/install.inc
+++ b/core/includes/install.inc
@@ -268,11 +268,9 @@
       'value' => array(
         CONFIG_ACTIVE_DIRECTORY => array(
           'path' => 'config/active_' . drupal_hash_base64(drupal_random_bytes(55)),
-          'absolute' => FALSE,
         ),
         CONFIG_STAGING_DIRECTORY => array(
           'path' => 'config/staging_' . drupal_hash_base64(drupal_random_bytes(55)),
-          'absolute' => FALSE,
         ),
       ),
       'required' => TRUE,