Index: Ringtoets/Piping/src/Ringtoets.Piping.Data/PipingCalculation.cs
===================================================================
diff -u -rd49a06fcbf63b36885b0d8f09a01f6539bcbfd56 -r7c3056aafbb670d79d239ef3d38e9d942bc33498
--- Ringtoets/Piping/src/Ringtoets.Piping.Data/PipingCalculation.cs	(.../PipingCalculation.cs)	(revision d49a06fcbf63b36885b0d8f09a01f6539bcbfd56)
+++ Ringtoets/Piping/src/Ringtoets.Piping.Data/PipingCalculation.cs	(.../PipingCalculation.cs)	(revision 7c3056aafbb670d79d239ef3d38e9d942bc33498)
@@ -21,6 +21,7 @@
 
 using System;
 using Core.Common.Base;
+using Ringtoets.Common.Data;
 using Ringtoets.Common.Data.Calculation;
 using RingtoetsCommonDataResources = Ringtoets.Common.Data.Properties.Resources;
 
@@ -40,8 +41,8 @@
         public PipingCalculation(GeneralPipingInput generalInputParameters)
         {
             Name = RingtoetsCommonDataResources.Calculation_DefaultName;
-
             InputParameters = new PipingInput(generalInputParameters);
+            Comments = new Commentable();
         }
 
         /// <summary>
@@ -69,7 +70,7 @@
             }
         }
 
-        public string Comments { get; set; }
+        public Commentable Comments { get; private set; }
 
         public void ClearOutput()
         {