Customizing tableheader.js Sticky table Header
You can override tableheader.js using hook_js_alter(&amp;js) {}, just replace path of file, like in example (details here).

Also you can override Drupal.settings.tableHeaderOffset value.
Thus, in template.php place something like this:

drupal_add_js('themeTableHeaderOffset() { return 200; }', 'inline');
drupal_add_js(array('tableHeaderOffset' =&gt; 'themeTableHeaderOffset'), 'setting');