Venetian add a 3rd column to header template for site description.

example.php

/**
 * We don't want the site title and tagline to be in the same block for "site branding"
 * on this theme.
 *
 * We will want to override the default site_title/tagline action included,
 * and make our own.  The default action is added in the header locations of
 * the config as '[action]boldgrid_site_identity', so we will put our own
 * custom override in as '[action]venetian_site_title'.
 *
 * This is what the markup is being displayed as currently in venetian:
 *
 * 		<div class="site-branding">
 *			<?php do_action( 'boldgrid_site_title' ); ?>
 *			<?php do_action( 'boldgrid_print_tagline' ); ?>
 *		</div><!-- .site-branding -->
 *
 * Those actions are what output the site title markup and the tagline markup.
 * We can use those hooks in our new method, venetian_site_title, so things
 * work automatically and we don't have to rewrite any of the logic used.
 */
function venetian_site_title() {
	?>
	<div class="site-branding">
		<?php do_action( 'boldgrid_site_title' ); ?>
	</div>
	<?php
}

add_action( 'venetian_site_title', 'venetian_site_title' );

/**
 * This removes the tagline from the site title location, and we will
 * want to add in our own custom tagline area, somewhere in our template.
 */
function venetian_site_tagline() {
	?>
	<div class="site-tagline">
		<?php do_action( 'boldgrid_print_tagline' ); ?>
	</div>
	<?php
}

add_action( 'venetian_site_tagline', 'venetian_site_tagline' );

/**
 * This will add our custom sections to the three col-md-4 bootstrap columns
 * layout.
 */
function venetian_custom_header( $configs ) {

	// Assign Locations for Generic Header.
	$configs['template']['locations']['header'] = array(
			'2' => array( '[action]venetian_site_title' ),
			'3' => array( '[action]venetian_site_tagline' ),
			'4' => array( '[menu]social', '[menu]primary' ),
			'5' => array( '[widget]boldgrid-widget-2' ),
			'8' => array( '[menu]tertiary' ),
	);
	return $configs;
}

add_filter( 'boldgrid_theme_framework_config', 'venetian_custom_header' );