I thought about this and I came up with a different solution. Assuming your plugin has a field called "class" in the XML. $app = JFactory::getApplication(); $appParams = $app->getParams(); $class = ""; if ($this->params['class']) { $class = $this->params['class']; } $pageClass = $appParams['pageclass_sfx']; if(!empty($pageClass)) { $class = " " . $this->params['class']; } else { $class = $this->params['class']; } $pageClass = $pageClass . $class; $app->setParams($pageClass); As the menu/page class is already added to the body we can just concatenate ur new class