diff --git a/phpBB/includes/acp/acp_forums.php b/phpBB/includes/acp/acp_forums.php
index edeac78d22..69c44f9edc 100644
--- a/phpBB/includes/acp/acp_forums.php
+++ b/phpBB/includes/acp/acp_forums.php
@@ -1817,7 +1817,7 @@ class acp_forums
 		$row = $db->sql_fetchrow($result);
 		$db->sql_freeresult($result);
 
-		set_config('upload_dir_size', (int) $row['stat'], true);
+		set_config('upload_dir_size', (float) $row['stat'], true);
 
 		return array();
 	}
diff --git a/phpBB/includes/acp/acp_main.php b/phpBB/includes/acp/acp_main.php
index aaafca890b..981ffa7b1b 100644
--- a/phpBB/includes/acp/acp_main.php
+++ b/phpBB/includes/acp/acp_main.php
@@ -165,7 +165,7 @@ class acp_main
 							FROM ' . ATTACHMENTS_TABLE . '
 							WHERE is_orphan = 0';
 						$result = $db->sql_query($sql);
-						set_config('upload_dir_size', (int) $db->sql_fetchfield('stat'), true);
+						set_config('upload_dir_size', (float) $db->sql_fetchfield('stat'), true);
 						$db->sql_freeresult($result);
 
 						if (!function_exists('update_last_username'))
diff --git a/phpBB/includes/functions_convert.php b/phpBB/includes/functions_convert.php
index 680ad38adf..181a32fab2 100644
--- a/phpBB/includes/functions_convert.php
+++ b/phpBB/includes/functions_convert.php
@@ -1952,7 +1952,7 @@ function update_dynamic_config()
 		FROM ' . ATTACHMENTS_TABLE . '
 		WHERE is_orphan = 0';
 	$result = $db->sql_query($sql);
-	set_config('upload_dir_size', (int) $db->sql_fetchfield('stat'), true);
+	set_config('upload_dir_size', (float) $db->sql_fetchfield('stat'), true);
 	$db->sql_freeresult($result);
 
 	/**