diff --git a/src/Perspex.Controls/TextBlock.cs b/src/Perspex.Controls/TextBlock.cs
index d9e1c5520d..29a760b11f 100644
--- a/src/Perspex.Controls/TextBlock.cs
+++ b/src/Perspex.Controls/TextBlock.cs
@@ -102,6 +102,9 @@ namespace Perspex.Controls
         static TextBlock()
         {
             AffectsRender(ForegroundProperty);
+            AffectsRender(FontWeightProperty);
+            AffectsRender(FontSizeProperty);
+            AffectsRender(FontStyleProperty);
         }
 
         /// <summary>
@@ -113,7 +116,8 @@ namespace Perspex.Controls
                 this.GetObservable(TextProperty).Select(_ => Unit.Default),
                 this.GetObservable(TextAlignmentProperty).Select(_ => Unit.Default),
                 this.GetObservable(FontSizeProperty).Select(_ => Unit.Default),
-                this.GetObservable(FontStyleProperty).Select(_ => Unit.Default))
+                this.GetObservable(FontStyleProperty).Select(_ => Unit.Default),
+                this.GetObservable(FontWeightProperty).Select(_=>Unit.Default))
                 .Subscribe(_ =>
                 {
                     InvalidateFormattedText();