What specifically do you mean by a floating pane? Do you mean a ContentPane when its PaneLocation is FloatingOnly/FloatingDockable? If so then you can use a style trigger to retemplate the ContentPane. If you mean to alter the "chrome" of the PaneToolWindow (which is the element used to host 1 or more panes within a floating window, then you would retemplate that element either putting a Style in the Application.Resources or specifically setting its style in the ToolWindowLoaded event. Note, by default when displayed within a windows application (i.e. non-xbap) the os is providing the chrome just as it does for a standard wpf Window element so you would have to set the UseOSNonClientArea of the (Pane)ToolWindow to false to hide the os chrome and use the chrome you would provide in the template you create for it.