Index: Riskeer/Integration/test/Riskeer.Integration.Forms.Test/PropertyClasses/NormPropertiesIntegrationTest.cs
===================================================================
diff -u -r08d598cf2708d176aa1be3fd7f364f189b86d65f -r418a1ea0ec32c35a910714f804b3b75abd74fd92
--- Riskeer/Integration/test/Riskeer.Integration.Forms.Test/PropertyClasses/NormPropertiesIntegrationTest.cs	(.../NormPropertiesIntegrationTest.cs)	(revision 08d598cf2708d176aa1be3fd7f364f189b86d65f)
+++ Riskeer/Integration/test/Riskeer.Integration.Forms.Test/PropertyClasses/NormPropertiesIntegrationTest.cs	(.../NormPropertiesIntegrationTest.cs)	(revision 418a1ea0ec32c35a910714f804b3b75abd74fd92)
@@ -87,10 +87,7 @@
             SetOutputToHydraulicBoundaryLocationCalculations(assessmentSection.GrassCoverErosionOutwards, hydraulicBoundaryLocation1, random);
 
             var emptyPipingCalculation = new TestPipingCalculation();
-            var pipingCalculation = new TestPipingCalculation
-            {
-                Output = PipingOutputTestFactory.Create()
-            };
+            var pipingCalculation = new TestPipingCalculation(true);
             var emptyGrassCoverErosionInwardsCalculation = new GrassCoverErosionInwardsCalculation();
             var grassCoverErosionInwardsCalculation = new GrassCoverErosionInwardsCalculation
             {
@@ -180,10 +177,7 @@
             });
             SetOutputToHydraulicBoundaryLocationCalculations(assessmentSection.GrassCoverErosionOutwards, hydraulicBoundaryLocation, random);
 
-            var pipingCalculation = new TestPipingCalculation
-            {
-                Output = PipingOutputTestFactory.Create()
-            };
+            var pipingCalculation = new TestPipingCalculation(true);
             var grassCoverErosionInwardsCalculation = new GrassCoverErosionInwardsCalculation
             {
                 Output = new TestGrassCoverErosionInwardsOutput()
Index: Riskeer/Piping/test/Riskeer.Piping.Data.TestUtil/TestPipingCalculation.cs
===================================================================
diff -u -re1228b228633bd834e448a5c5e48eccd29852287 -r418a1ea0ec32c35a910714f804b3b75abd74fd92
--- Riskeer/Piping/test/Riskeer.Piping.Data.TestUtil/TestPipingCalculation.cs	(.../TestPipingCalculation.cs)	(revision e1228b228633bd834e448a5c5e48eccd29852287)
+++ Riskeer/Piping/test/Riskeer.Piping.Data.TestUtil/TestPipingCalculation.cs	(.../TestPipingCalculation.cs)	(revision 418a1ea0ec32c35a910714f804b3b75abd74fd92)
@@ -28,6 +28,8 @@
     /// </summary>
     public class TestPipingCalculation : PipingCalculation<PipingInput, PipingOutput>
     {
+        private bool hasOutput;
+
         /// <summary>
         /// Creates a new instance of <see cref="TestPipingCalculation"/> with default <see cref="PipingInput"/>.
         /// </summary>
@@ -43,14 +45,14 @@
         /// is <c>null</c>.</exception>
         public TestPipingCalculation(PipingInput pipingInput, bool hasOutput = false) : base(pipingInput)
         {
-            HasOutput = hasOutput;
+            this.hasOutput = hasOutput;
         }
 
-        public override bool HasOutput { get; }
+        public override bool HasOutput => hasOutput;
 
         public override void ClearOutput()
         {
-            // Do nothing
+            hasOutput = false;
         }
     }
 }
\ No newline at end of file