There are two problems with WPF windows when the WindowStyle=None option is used.
If only one monitor is used another simple approach is to set the maximum height of the window. The System.Windows.SystemParameters class provides some usefull values e.g. PrimaryScreenHeight or MaximizedPrimaryScreenHeight.
In my sample code i use MaximizedPrimaryScreenHeight and subtract the ResizeBorderThickness i set in WindowChrome.
using System.Windows;
using System.Windows.Shell;
public partial class MainWindow : Window
{
public MainWindow()
{
InitializeComponent();
Thickness resizeBorderThickness = WindowChrome.GetWindowChrome(this).ResizeBorderThickness;
this.MaxHeight = SystemParameters.MaximizedPrimaryScreenHeight - resizeBorderThickness.Top - resizeBorderThickness.Bottom;
}
}