Magento 1.9- Magento Sort Attribute by Decimal not Alphanumerically

The best solution I found was to override the ORDER BY for the query by calling a primitive method of the Collection class, here's the example they give:

$_productCollection = Mage::getModel('catalog/product')->getCollection();
$_productCollection->setOrder('weight', 'asc');
$_productCollection->getSelect()->reset(Zend_Db_Select::ORDER);
$_productCollection->getSelect()->order('CAST(`weight` AS SIGNED) ASC'));