diff --git a/src/PhpWord/Escaper/Xml.php b/src/PhpWord/Escaper/Xml.php
index a769c5e189..316ee85e63 100644
--- a/src/PhpWord/Escaper/Xml.php
+++ b/src/PhpWord/Escaper/Xml.php
@@ -27,6 +27,6 @@ class Xml extends AbstractEscaper
     protected function escapeSingleValue($input)
     {
         // todo: omit encoding parameter after migration onto PHP 5.4
-        return htmlspecialchars($input, ENT_QUOTES, 'UTF-8');
+        return (!is_null($input)) ? htmlspecialchars($input, ENT_QUOTES, 'UTF-8') : '';
     }
 }
diff --git a/src/PhpWord/TemplateProcessor.php b/src/PhpWord/TemplateProcessor.php
index 664d46887e..09f5461995 100644
--- a/src/PhpWord/TemplateProcessor.php
+++ b/src/PhpWord/TemplateProcessor.php
@@ -257,11 +257,11 @@ protected static function ensureMacroCompleted($macro)
      */
     protected static function ensureUtf8Encoded($subject)
     {
-        if (!Text::isUTF8($subject)) {
+        if (!Text::isUTF8($subject) && !is_null($subject)) {
             $subject = utf8_encode($subject);
         }
 
-        return $subject;
+        return (!is_null($subject)) ? $subject : '';
     }
 
     /**