Index: Ringtoets/Integration/src/Ringtoets.Integration.Data/StandAlone/AssemblyFactories/GrassCoverSlipOffOutwardsFailureMechanismSectionResultAssemblyFactory.cs
===================================================================
diff -u -ra593329f1dbecbec57185718a2d2ed09bdb9dc14 -rae9999ca55b34f4d126084a09cd08210cbdca70e
--- Ringtoets/Integration/src/Ringtoets.Integration.Data/StandAlone/AssemblyFactories/GrassCoverSlipOffOutwardsFailureMechanismSectionResultAssemblyFactory.cs	(.../GrassCoverSlipOffOutwardsFailureMechanismSectionResultAssemblyFactory.cs)	(revision a593329f1dbecbec57185718a2d2ed09bdb9dc14)
+++ Ringtoets/Integration/src/Ringtoets.Integration.Data/StandAlone/AssemblyFactories/GrassCoverSlipOffOutwardsFailureMechanismSectionResultAssemblyFactory.cs	(.../GrassCoverSlipOffOutwardsFailureMechanismSectionResultAssemblyFactory.cs)	(revision ae9999ca55b34f4d126084a09cd08210cbdca70e)
@@ -131,5 +131,41 @@
                 throw new AssemblyException(e.Message, e);
             }
         }
+
+        /// <summary>
+        /// Assembles the combined assembly.
+        /// </summary>
+        /// <param name="failureMechanismSectionResult">The failure mechanism section result to
+        /// combine the assemblies for.</param>
+        /// <returns>A <see cref="FailureMechanismSectionAssemblyCategoryGroup"/>.</returns>
+        /// <exception cref="ArgumentNullException">Thrown when <paramref name="failureMechanismSectionResult"/>
+        /// is <c>null</c>.</exception>
+        /// <exception cref="AssemblyException">Thrown when the <see cref="FailureMechanismSectionAssemblyCategoryGroup"/>
+        /// could not be created.</exception>
+        public static FailureMechanismSectionAssemblyCategoryGroup AssembleCombinedAssessment(
+            GrassCoverSlipOffOutwardsFailureMechanismSectionResult failureMechanismSectionResult)
+        {
+            if (failureMechanismSectionResult == null)
+            {
+                throw new ArgumentNullException(nameof(failureMechanismSectionResult));
+            }
+
+            FailureMechanismSectionAssemblyCategoryGroup simpleAssembly = AssembleSimpleAssessment(failureMechanismSectionResult);
+            FailureMechanismSectionAssemblyCategoryGroup detailedAssembly = AssembleDetailedAssessment(failureMechanismSectionResult);
+            FailureMechanismSectionAssemblyCategoryGroup tailorMadeAssembly = AssembleTailorMadeAssessment(failureMechanismSectionResult);
+
+            IAssemblyToolCalculatorFactory calculatorFactory = AssemblyToolCalculatorFactory.Instance;
+            IFailureMechanismSectionAssemblyCalculator calculator =
+                calculatorFactory.CreateFailureMechanismSectionAssemblyCalculator(AssemblyToolKernelFactory.Instance);
+
+            try
+            {
+                return calculator.AssembleCombined(simpleAssembly, detailedAssembly, tailorMadeAssembly);
+            }
+            catch (FailureMechanismSectionAssemblyCalculatorException e)
+            {
+                throw new AssemblyException(e.Message, e);
+            }
+        }
     }
 }
\ No newline at end of file
Index: Ringtoets/Integration/test/Ringtoets.Integration.Data.Test/StandAlone/AssemblyFactories/GrassCoverSlipOffOutwardsFailureMechanismSectionResultAssemblyFactoryTest.cs
===================================================================
diff -u -ra593329f1dbecbec57185718a2d2ed09bdb9dc14 -rae9999ca55b34f4d126084a09cd08210cbdca70e
--- Ringtoets/Integration/test/Ringtoets.Integration.Data.Test/StandAlone/AssemblyFactories/GrassCoverSlipOffOutwardsFailureMechanismSectionResultAssemblyFactoryTest.cs	(.../GrassCoverSlipOffOutwardsFailureMechanismSectionResultAssemblyFactoryTest.cs)	(revision a593329f1dbecbec57185718a2d2ed09bdb9dc14)
+++ Ringtoets/Integration/test/Ringtoets.Integration.Data.Test/StandAlone/AssemblyFactories/GrassCoverSlipOffOutwardsFailureMechanismSectionResultAssemblyFactoryTest.cs	(.../GrassCoverSlipOffOutwardsFailureMechanismSectionResultAssemblyFactoryTest.cs)	(revision ae9999ca55b34f4d126084a09cd08210cbdca70e)
@@ -144,7 +144,7 @@
 
             using (new AssemblyToolCalculatorFactoryConfig())
             {
-                var calculatorFactory = (TestAssemblyToolCalculatorFactory)AssemblyToolCalculatorFactory.Instance;
+                var calculatorFactory = (TestAssemblyToolCalculatorFactory) AssemblyToolCalculatorFactory.Instance;
                 FailureMechanismSectionAssemblyCalculatorStub calculator = calculatorFactory.LastCreatedFailureMechanismSectionAssemblyCalculator;
 
                 // Call
@@ -163,7 +163,7 @@
 
             using (new AssemblyToolCalculatorFactoryConfig())
             {
-                var calculatorFactory = (TestAssemblyToolCalculatorFactory)AssemblyToolCalculatorFactory.Instance;
+                var calculatorFactory = (TestAssemblyToolCalculatorFactory) AssemblyToolCalculatorFactory.Instance;
                 FailureMechanismSectionAssemblyCalculatorStub calculator = calculatorFactory.LastCreatedFailureMechanismSectionAssemblyCalculator;
 
                 // Call
@@ -184,7 +184,7 @@
 
             using (new AssemblyToolCalculatorFactoryConfig())
             {
-                var calculatorfactory = (TestAssemblyToolCalculatorFactory)AssemblyToolCalculatorFactory.Instance;
+                var calculatorfactory = (TestAssemblyToolCalculatorFactory) AssemblyToolCalculatorFactory.Instance;
                 FailureMechanismSectionAssemblyCalculatorStub calculator = calculatorfactory.LastCreatedFailureMechanismSectionAssemblyCalculator;
                 calculator.ThrowExceptionOnCalculate = true;
 
@@ -222,7 +222,7 @@
 
             using (new AssemblyToolCalculatorFactoryConfig())
             {
-                var calculatorFactory = (TestAssemblyToolCalculatorFactory)AssemblyToolCalculatorFactory.Instance;
+                var calculatorFactory = (TestAssemblyToolCalculatorFactory) AssemblyToolCalculatorFactory.Instance;
                 FailureMechanismSectionAssemblyCalculatorStub calculator = calculatorFactory.LastCreatedFailureMechanismSectionAssemblyCalculator;
 
                 // Call
@@ -241,7 +241,7 @@
 
             using (new AssemblyToolCalculatorFactoryConfig())
             {
-                var calculatorFactory = (TestAssemblyToolCalculatorFactory)AssemblyToolCalculatorFactory.Instance;
+                var calculatorFactory = (TestAssemblyToolCalculatorFactory) AssemblyToolCalculatorFactory.Instance;
                 FailureMechanismSectionAssemblyCalculatorStub calculator = calculatorFactory.LastCreatedFailureMechanismSectionAssemblyCalculator;
 
                 // Call
@@ -262,7 +262,7 @@
 
             using (new AssemblyToolCalculatorFactoryConfig())
             {
-                var calculatorfactory = (TestAssemblyToolCalculatorFactory)AssemblyToolCalculatorFactory.Instance;
+                var calculatorfactory = (TestAssemblyToolCalculatorFactory) AssemblyToolCalculatorFactory.Instance;
                 FailureMechanismSectionAssemblyCalculatorStub calculator = calculatorfactory.LastCreatedFailureMechanismSectionAssemblyCalculator;
                 calculator.ThrowExceptionOnCalculate = true;
 
@@ -278,5 +278,92 @@
         }
 
         #endregion
+
+        #region Combined Assembly
+
+        [Test]
+        public void AssembleCombinedAssessment_FailureMechanismSectionResultNull_ThrowsArgumentNullException()
+        {
+            // Call
+            TestDelegate call = () => GrassCoverSlipOffOutwardsFailureMechanismSectionResultAssemblyFactory.AssembleCombinedAssessment(null);
+
+            // Assert
+            var exception = Assert.Throws<ArgumentNullException>(call);
+            Assert.AreEqual("failureMechanismSectionResult", exception.ParamName);
+        }
+
+        [Test]
+        public void AssembleCombinedAssessment_WithInput_SetsInputOnCalculator()
+        {
+            // Setup
+            var sectionResult = new GrassCoverSlipOffOutwardsFailureMechanismSectionResult(FailureMechanismSectionTestFactory.CreateFailureMechanismSection());
+
+            using (new AssemblyToolCalculatorFactoryConfig())
+            {
+                var calculatorFactory = (TestAssemblyToolCalculatorFactory) AssemblyToolCalculatorFactory.Instance;
+                FailureMechanismSectionAssemblyCalculatorStub calculator = calculatorFactory.LastCreatedFailureMechanismSectionAssemblyCalculator;
+
+                // Call
+                GrassCoverSlipOffOutwardsFailureMechanismSectionResultAssemblyFactory.AssembleCombinedAssessment(sectionResult);
+
+                // Assert
+                FailureMechanismSectionAssemblyCategoryGroup expectedSimpleAssembly = GrassCoverSlipOffOutwardsFailureMechanismSectionResultAssemblyFactory.AssembleSimpleAssessment(
+                    sectionResult);
+                FailureMechanismSectionAssemblyCategoryGroup expectedDetailedAssembly = GrassCoverSlipOffOutwardsFailureMechanismSectionResultAssemblyFactory.AssembleDetailedAssessment(
+                    sectionResult);
+                FailureMechanismSectionAssemblyCategoryGroup expectedTailorMadeAssembly = GrassCoverSlipOffOutwardsFailureMechanismSectionResultAssemblyFactory.AssembleTailorMadeAssessment(
+                    sectionResult);
+
+                Assert.AreEqual(expectedSimpleAssembly, calculator.CombinedSimpleAssemblyGroupInput);
+                Assert.AreEqual(expectedDetailedAssembly, calculator.CombinedDetailedAssemblyGroupInput);
+                Assert.AreEqual(expectedTailorMadeAssembly, calculator.CombinedTailorMadeAssemblyGroupInput);
+            }
+        }
+
+        [Test]
+        public void AssembleCombinedAssessment_AssemblyRan_ReturnsOutput()
+        {
+            // Setup
+            var sectionResult = new GrassCoverSlipOffOutwardsFailureMechanismSectionResult(FailureMechanismSectionTestFactory.CreateFailureMechanismSection());
+
+            using (new AssemblyToolCalculatorFactoryConfig())
+            {
+                var calculatorFactory = (TestAssemblyToolCalculatorFactory) AssemblyToolCalculatorFactory.Instance;
+                FailureMechanismSectionAssemblyCalculatorStub calculator = calculatorFactory.LastCreatedFailureMechanismSectionAssemblyCalculator;
+
+                // Call
+                FailureMechanismSectionAssemblyCategoryGroup actualOutput =
+                    GrassCoverSlipOffOutwardsFailureMechanismSectionResultAssemblyFactory.AssembleCombinedAssessment(sectionResult);
+
+                // Assert
+                FailureMechanismSectionAssemblyCategoryGroup? calculatorOutput = calculator.CombinedAssemblyCategoryOutput;
+                Assert.AreEqual(calculatorOutput, actualOutput);
+            }
+        }
+
+        [Test]
+        public void AssembleCombinedAssessment_CalculatorThrowsExceptions_ThrowsAssemblyException()
+        {
+            // Setup
+            var sectionResult = new GrassCoverSlipOffOutwardsFailureMechanismSectionResult(FailureMechanismSectionTestFactory.CreateFailureMechanismSection());
+
+            using (new AssemblyToolCalculatorFactoryConfig())
+            {
+                var calculatorfactory = (TestAssemblyToolCalculatorFactory) AssemblyToolCalculatorFactory.Instance;
+                FailureMechanismSectionAssemblyCalculatorStub calculator = calculatorfactory.LastCreatedFailureMechanismSectionAssemblyCalculator;
+                calculator.ThrowExceptionOnCalculateCombinedAssembly = true;
+
+                // Call
+                TestDelegate call = () => GrassCoverSlipOffOutwardsFailureMechanismSectionResultAssemblyFactory.AssembleCombinedAssessment(sectionResult);
+
+                // Assert
+                var exception = Assert.Throws<AssemblyException>(call);
+                Exception innerException = exception.InnerException;
+                Assert.IsInstanceOf<FailureMechanismSectionAssemblyCalculatorException>(innerException);
+                Assert.AreEqual(innerException.Message, exception.Message);
+            }
+        }
+
+        #endregion
     }
 }
\ No newline at end of file