Codice HTML:

<!-- Preloader -->
  <div id="preloader">
    <div id="status">&nbsp;</div>
  </div>
<!-- Preloader fine -->



<!-- Libreria jQuery  -->
<script src="https://code.jquery.com/jquery-2.1.3.min.js"></script>

Codice CSS:

* {
  padding:0;
  margin:0;
}
#preloader {
  position:fixed; 
  top:0; 
  left:0; 
  right:0;
  bottom:0;
  background-color:#c4ebe8;
  z-index:99999; 
}
#status { 
  width:400px;
  height:300px;
  position:absolute;
  left:50%; 
  top:50%;
  background-image:url(http://i.imgur.com/MSzY4fK.gif); 
  background-repeat:no-repeat; 
  background-position:center; 
  margin:-150px 0 0 -200px;
}

Codice JS:

    // inserire nel HEAD tra i tag SCRIPT
      
        
        $(window).load(function() { 
            $('#status').fadeOut(); 
            $('#preloader').delay(350).fadeOut('slow'); 
            $('body').delay(350).css({'overflow':'hidden'});
        })