Index: src/Deltares.DSoilModel.Forms/DSoilModelContext.cs
===================================================================
diff -u -r664 -r681
--- src/Deltares.DSoilModel.Forms/DSoilModelContext.cs	(.../DSoilModelContext.cs)	(revision 664)
+++ src/Deltares.DSoilModel.Forms/DSoilModelContext.cs	(.../DSoilModelContext.cs)	(revision 681)
@@ -161,6 +161,19 @@
                 return false;
             }
 
+            var boring = source as Boring;
+            if (boring != null)
+            {
+                if (member == boring.GetMemberName(b => b.TopVoid) ||
+                    member == boring.GetMemberName(b => b.BottomVoid) ||
+                    member == boring.GetMemberName(b => b.MedianVoid) ||
+                    member == boring.GetMemberName(b => b.GammaSatVoid) ||
+                    member == boring.GetMemberName(b => b.GammaUnsatVoid))
+                {
+                    return false;
+                }
+            }
+            
             var layer = source as BoringLayer;
             if (layer != null)
             {