Module.php

public function getServiceConfig()
{
    return array(
        'factories' => array(
            'navigation' => 'ModuleNamespace\Navigation\Service\NavigationFactory',
        )
    );
}

ModuleNamespace\Navigation\Service\NavigationFactory

<?php

namespace ModuleNamespace\Navigation\Service;

use Zend\ServiceManager\ServiceLocatorInterface;

class NavigationFactory extends \Zend\Navigation\Service\DefaultNavigationFactory
{
    public function createService(ServiceLocatorInterface $serviceLocator)
    {
        return new \ModuleNamespace\Model\Navigation();
    }
}

ModuleNamespace\Model;

class Navigation extends \Zend\Navigation\Navigation
{
    public function __construct()
    {
        $home = new \Zend\Navigation\Page\Mvc();

        $home->setLabel('Home')
             ->setController('index')
             ->setAction('index');

        $this->addPage($home);


        $contact = new \Zend\Navigation\Page\Mvc();

        $contact->setLabel('Contact')
                ->setController('contact')
                ->setAction('index');

        $this->addPage($contact);
    }
}

layout.phtml

<?php echo $this->navigation('navigation')
                ->menu()
                ->setMaxDepth(0)
                ->setRenderInvisible(false) ?>