diff --git a/Objects/Objects/BuiltElements/Beam.cs b/Objects/Objects/BuiltElements/Beam.cs
index 8931a6de34..0f4396ed88 100644
--- a/Objects/Objects/BuiltElements/Beam.cs
+++ b/Objects/Objects/BuiltElements/Beam.cs
@@ -141,10 +141,12 @@ public override Level? level
       get => archicadLevel;
       internal set
       {
-        if (value is not ArchicadLevel l)
-          throw new ArgumentException($"Expected object of type {nameof(ArchicadLevel)}");
+        if (value is ArchicadLevel or null)
+        {
+          archicadLevel = value as ArchicadLevel;
+        }
 
-        archicadLevel = l;
+        throw new ArgumentException($"Expected object of type {nameof(ArchicadLevel)}");
       }
     }
 
diff --git a/Objects/Objects/BuiltElements/Column.cs b/Objects/Objects/BuiltElements/Column.cs
index db62a85988..b0ef02c697 100644
--- a/Objects/Objects/BuiltElements/Column.cs
+++ b/Objects/Objects/BuiltElements/Column.cs
@@ -167,10 +167,12 @@ public override Level? level
       get => archicadLevel;
       internal set
       {
-        if (value is not ArchicadLevel l)
-          throw new ArgumentException($"Expected object of type {nameof(ArchicadLevel)}");
+        if (value is ArchicadLevel or null)
+        {
+          archicadLevel = value as ArchicadLevel;
+        }
 
-        archicadLevel = l;
+        throw new ArgumentException($"Expected object of type {nameof(ArchicadLevel)}");
       }
     }
 
diff --git a/Objects/Objects/BuiltElements/Floor.cs b/Objects/Objects/BuiltElements/Floor.cs
index d83e0f071d..3fcdf4c837 100644
--- a/Objects/Objects/BuiltElements/Floor.cs
+++ b/Objects/Objects/BuiltElements/Floor.cs
@@ -103,10 +103,12 @@ public override Level? level
       get => archicadLevel;
       internal set
       {
-        if (value is not ArchicadLevel l)
-          throw new ArgumentException($"Expected object of type {nameof(ArchicadLevel)}");
+        if (value is ArchicadLevel or null)
+        {
+          archicadLevel = value as ArchicadLevel;
+        }
 
-        archicadLevel = l;
+        throw new ArgumentException($"Expected object of type {nameof(ArchicadLevel)}");
       }
     }
 
diff --git a/Objects/Objects/BuiltElements/Roof.cs b/Objects/Objects/BuiltElements/Roof.cs
index 1683354b7e..02979d3766 100644
--- a/Objects/Objects/BuiltElements/Roof.cs
+++ b/Objects/Objects/BuiltElements/Roof.cs
@@ -153,10 +153,12 @@ public override Level? level
       get => archicadLevel;
       internal set
       {
-        if (value is not ArchicadLevel l)
-          throw new ArgumentException($"Expected object of type {nameof(ArchicadLevel)}");
+        if (value is ArchicadLevel or null)
+        {
+          archicadLevel = value as ArchicadLevel;
+        }
 
-        archicadLevel = l;
+        throw new ArgumentException($"Expected object of type {nameof(ArchicadLevel)}");
       }
     }
 
diff --git a/Objects/Objects/BuiltElements/Wall.cs b/Objects/Objects/BuiltElements/Wall.cs
index 051c69294c..a5dd9d358b 100644
--- a/Objects/Objects/BuiltElements/Wall.cs
+++ b/Objects/Objects/BuiltElements/Wall.cs
@@ -308,10 +308,12 @@ public override Level? level
       get => archicadLevel;
       internal set
       {
-        if (value is not ArchicadLevel l)
-          throw new ArgumentException($"Expected object of type {nameof(ArchicadLevel)}");
+        if (value is ArchicadLevel or null)
+        {
+          archicadLevel = value as ArchicadLevel;
+        }
 
-        archicadLevel = l;
+        throw new ArgumentException($"Expected object of type {nameof(ArchicadLevel)}");
       }
     }