Determining the title bar height of a GUI Window

Is there any way to determine the height/width of a title bar of a GUI.Window? Because, everytime you add a new component in the window, and If i place it (0,0,50,50) its overlapping the GUI.Window title bar. Is there any way to make the component appear inside the body of the window rather than the whole Window itself?

If you are using GUILayout inside the window, then you should be using GUILayout.Window to create the window too, not GUI.Window.