Index: Core/Gui/src/Core.Gui/Forms/ViewHost/AvalonDockViewHost.xaml
===================================================================
diff -u -rd6b7ed144b128f034c3a8d18671e42aae9eacc3e -r9e3aff6b1c4dce35cb383fd84b9dd89fae6e4c07
--- Core/Gui/src/Core.Gui/Forms/ViewHost/AvalonDockViewHost.xaml	(.../AvalonDockViewHost.xaml)	(revision d6b7ed144b128f034c3a8d18671e42aae9eacc3e)
+++ Core/Gui/src/Core.Gui/Forms/ViewHost/AvalonDockViewHost.xaml	(.../AvalonDockViewHost.xaml)	(revision 9e3aff6b1c4dce35cb383fd84b9dd89fae6e4c07)
@@ -28,8 +28,7 @@
              xmlns:xcad="http://schemas.xceed.com/wpf/xaml/avalondock"
              xmlns:viewHost="clr-namespace:Core.Gui.Forms.ViewHost"
              mc:Ignorable="d" 
-             d:DesignHeight="300" d:DesignWidth="300"
-             d:DataContext="{d:DesignInstance IsDesignTimeCreatable=False, Type={x:Type viewHost:CustomLayoutAnchorable}}">
+             d:DesignHeight="300" d:DesignWidth="300">
     
     <UserControl.Resources>
         <ResourceDictionary>
@@ -46,14 +45,24 @@
             <xcad:DockingManager.DocumentHeaderTemplate>
                 <DataTemplate>
                     <StackPanel Orientation="Horizontal">
-                        <Image Source="{Binding IconSource}" Margin="0,0,4,0" Height="16" Width="16"/>
+                        <StackPanel.DataContext>
+                            <viewHost:CustomLayoutDocument/>
+                        </StackPanel.DataContext>
+                        <TextBlock Style="{StaticResource ButtonIconStyle}"
+                                   Text="{Binding Symbol}"
+                                   FontFamily="{Binding FontFamily}"
+                                   Margin="0,0,4,0"
+                                   FontSize="16"/>
                         <TextBlock Text="{Binding Title}" TextTrimming="CharacterEllipsis"/>
                     </StackPanel>
                 </DataTemplate>
             </xcad:DockingManager.DocumentHeaderTemplate>
             <xcad:DockingManager.AnchorableHeaderTemplate>
                 <DataTemplate>
                     <StackPanel Orientation="Horizontal">
+                        <StackPanel.DataContext>
+                            <viewHost:CustomLayoutAnchorable/>
+                        </StackPanel.DataContext>
                         <TextBlock Style="{StaticResource ButtonIconStyle}"
                                    Text="{Binding Symbol}"
                                    Margin="0,0,4,0"
Index: Core/Gui/src/Core.Gui/Forms/ViewHost/CustomLayoutDocument.cs
===================================================================
diff -u
--- Core/Gui/src/Core.Gui/Forms/ViewHost/CustomLayoutDocument.cs	(revision 0)
+++ Core/Gui/src/Core.Gui/Forms/ViewHost/CustomLayoutDocument.cs	(revision 9e3aff6b1c4dce35cb383fd84b9dd89fae6e4c07)
@@ -0,0 +1,63 @@
+// Copyright (C) Stichting Deltares 2021. All rights reserved.
+//
+// This file is part of Riskeer.
+//
+// Riskeer is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+// 
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with this program. If not, see <http://www.gnu.org/licenses/>.
+//
+// All names, logos, and references to "Deltares" are registered trademarks of
+// Stichting Deltares and remain full property of Stichting Deltares at all times.
+// All rights reserved.
+
+using System.Windows;
+using System.Windows.Media;
+using Xceed.Wpf.AvalonDock.Layout;
+
+namespace Core.Gui.Forms.ViewHost
+{
+    /// <summary>
+    /// Custom implementation of <see cref="LayoutDocument"/>.
+    /// </summary>
+    public class CustomLayoutDocument : LayoutDocument
+    {
+        /// <summary>
+        /// The symbol <see cref="DependencyProperty"/>.
+        /// </summary>
+        public static readonly DependencyProperty SymbolProperty = DependencyProperty.Register(
+            "Symbol", typeof(string), typeof(CustomLayoutDocument), new PropertyMetadata(default(string)));
+
+        /// <summary>
+        /// The font family <see cref="DependencyProperty"/>.
+        /// </summary>
+        public static readonly DependencyProperty FontFamilyProperty = DependencyProperty.Register(
+            "FontFamily", typeof(FontFamily), typeof(CustomLayoutDocument), new PropertyMetadata(default(FontFamily)));
+
+        /// <summary>
+        /// Gets or sets the symbol.
+        /// </summary>
+        public string Symbol
+        {
+            get => (string) GetValue(SymbolProperty);
+            set => SetValue(SymbolProperty, value);
+        }
+
+        /// <summary>
+        /// Gets or sets the font family of the symbol.
+        /// </summary>
+        public FontFamily FontFamily
+        {
+            get => (FontFamily) GetValue(FontFamilyProperty);
+            set => SetValue(FontFamilyProperty, value);
+        }
+    }
+}
\ No newline at end of file
Index: Core/Gui/test/Core.Gui.Test/Forms/ViewHost/CustomLayoutDocumentTest.cs
===================================================================
diff -u
--- Core/Gui/test/Core.Gui.Test/Forms/ViewHost/CustomLayoutDocumentTest.cs	(revision 0)
+++ Core/Gui/test/Core.Gui.Test/Forms/ViewHost/CustomLayoutDocumentTest.cs	(revision 9e3aff6b1c4dce35cb383fd84b9dd89fae6e4c07)
@@ -0,0 +1,52 @@
+// Copyright (C) Stichting Deltares 2021. All rights reserved.
+//
+// This file is part of Riskeer.
+//
+// Riskeer is free software: you can redistribute it and/or modify
+// it under the terms of the GNU Lesser General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+// 
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+// GNU Lesser General Public License for more details.
+//
+// You should have received a copy of the GNU Lesser General Public License
+// along with this program. If not, see <http://www.gnu.org/licenses/>.
+//
+// All names, logos, and references to "Deltares" are registered trademarks of
+// Stichting Deltares and remain full property of Stichting Deltares at all times.
+// All rights reserved.
+
+using System.Windows.Media;
+using Core.Gui.Forms.ViewHost;
+using NUnit.Framework;
+using Xceed.Wpf.AvalonDock.Layout;
+
+namespace Core.Gui.Test.Forms.ViewHost
+{
+    [TestFixture]
+    public class CustomLayoutDocumentTest
+    {
+        [Test]
+        public void Constructor_ExpectedValues()
+        {
+            // Setup
+            const string symbol = "123";
+            var fontFamily = new FontFamily();
+
+            // Call
+            var layoutDocument = new CustomLayoutDocument
+            {
+                Symbol = symbol,
+                FontFamily = fontFamily
+            };
+
+            // Assert
+            Assert.IsInstanceOf<LayoutDocument>(layoutDocument);
+            Assert.AreEqual(symbol, layoutDocument.Symbol);
+            Assert.AreSame(fontFamily, layoutDocument.FontFamily);
+        }
+    }
+}
\ No newline at end of file