Index: Ringtoets/Common/src/Ringtoets.Common.Data/Calculation/ICalculatable.cs
===================================================================
diff -u
--- Ringtoets/Common/src/Ringtoets.Common.Data/Calculation/ICalculatable.cs	(revision 0)
+++ Ringtoets/Common/src/Ringtoets.Common.Data/Calculation/ICalculatable.cs	(revision 35cea5bdef5fedc2034ca0df05994b1930f7d46a)
@@ -0,0 +1,34 @@
+// Copyright (C) Stichting Deltares 2017. All rights reserved.
+//
+// This file is part of Ringtoets.
+//
+// Ringtoets is free software: you can redistribute it and/or modify
+// it under the terms of the GNU 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 General Public License for more details.
+//
+// You should have received a copy of the GNU 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.
+
+namespace Ringtoets.Common.Data.Calculation
+{
+    /// <summary>
+    /// An item for which a calculation can be performed.
+    /// </summary>
+    public interface ICalculatable
+    {
+        /// <summary>
+        /// Gets a value indicating whether or not the calculation should be performed.
+        /// </summary>
+        bool ShouldCalculate { get; }
+    }
+}
Index: Ringtoets/Common/src/Ringtoets.Common.Data/Ringtoets.Common.Data.csproj
===================================================================
diff -u -r2eabed6b453eb0b65487f121a83b67cf96a5d1d5 -r35cea5bdef5fedc2034ca0df05994b1930f7d46a
--- Ringtoets/Common/src/Ringtoets.Common.Data/Ringtoets.Common.Data.csproj	(.../Ringtoets.Common.Data.csproj)	(revision 2eabed6b453eb0b65487f121a83b67cf96a5d1d5)
+++ Ringtoets/Common/src/Ringtoets.Common.Data/Ringtoets.Common.Data.csproj	(.../Ringtoets.Common.Data.csproj)	(revision 35cea5bdef5fedc2034ca0df05994b1930f7d46a)
@@ -31,6 +31,7 @@
     <Compile Include="AssessmentSection\RingtoetsWellKnownTileSourceExtension.cs" />
     <Compile Include="AssessmentSection\WellKnownBackgroundDataConfiguration.cs" />
     <Compile Include="AssessmentSection\WmtsBackgroundDataConfiguration.cs" />
+    <Compile Include="Calculation\ICalculatable.cs" />
     <Compile Include="Comment.cs" />
     <Compile Include="Contribution\NormType.cs" />
     <Compile Include="DikeProfiles\BreakWater.cs" />