Loader for Asynchronous Page

Hi,

I have a website where in pages are loaded asynchronously. My site is little slow, pages will be just blank. I have used HTML loading code in my site custom code section. Loader will appear when the website is completely reloaded. But when I click on any button and it redirects to linked page, loader will not appear. Is there a way I can make loader appear on asynchronously loading pages?