<?php
$_productCollection=$this->getLoadedProductCollection();
$_helper = $this->helper('catalog/output');

$_productCollection->clear()
                    ->getSelect()
                    ->joinLeft(array('cpei'=>'catalog_product_entity_int'), 'e.entity_id = cpei.entity_id AND cpei.attribute_id = 197 AND cpei.store_id = 0', 'cpei.value as product_on_top' )
                    ->order( array( 'product_on_top DESC' ) );