UIWebView contentInset without extra height at bottom

It sounds like what you need is to adjust the webView.scrollView.contentSize and adjust the height by 64. You may need to provide more information about how it slides behind the nav bar and status bar to help me answer this. I would take a look at this section of the Scroll View Programming Guide:

http://developer.apple.com/library/ios/#documentation/WindowsViews/Conceptual/UIScrollView_pg/CreatingBasicScrollViews/CreatingBasicScrollViews.html

Change the clipsToBounds.

webView.clipsToBounds = NO;

This will make its content visible outside its frame, so set its frame like normal, right under the navigation bar. The navigation bar will be translucent and you will see its content under it.

Have you tried something like adjusting the webview's scrollview content insets? Example:

    webView.scrollView.contentInset = UIEdgeInsetsMake(0, 0,64, 0)