diff --git a/pcbnew/tools/pcb_editor_control.cpp b/pcbnew/tools/pcb_editor_control.cpp
index 6734765e32..79d2713579 100644
--- a/pcbnew/tools/pcb_editor_control.cpp
+++ b/pcbnew/tools/pcb_editor_control.cpp
@@ -73,7 +73,7 @@ private:
         // lines like this make me really think about a better name for SELECTION_CONDITIONS class
         bool mergeEnabled = ( SELECTION_CONDITIONS::MoreThan( 1 ) &&
                               /*SELECTION_CONDITIONS::OnlyType( PCB_ZONE_AREA_T ) &&*/
-                              SELECTION_CONDITIONS::SameNet() &&
+                              SELECTION_CONDITIONS::SameNet( true ) &&
                               SELECTION_CONDITIONS::SameLayer() )( selTool->GetSelection() );
 
         Enable( getMenuId( COMMON_ACTIONS::zoneMerge ), mergeEnabled );
diff --git a/pcbnew/tools/selection_conditions.cpp b/pcbnew/tools/selection_conditions.cpp
index 31a8d1a544..7d860a41a6 100644
--- a/pcbnew/tools/selection_conditions.cpp
+++ b/pcbnew/tools/selection_conditions.cpp
@@ -52,9 +52,9 @@ bool SELECTION_CONDITIONS::OnlyConnectedItems( const SELECTION& aSelection )
 }
 
 
-SELECTION_CONDITION SELECTION_CONDITIONS::SameNet()
+SELECTION_CONDITION SELECTION_CONDITIONS::SameNet( bool aAllowUnconnected )
 {
-    return boost::bind( &SELECTION_CONDITIONS::sameNetFunc, _1 );
+    return boost::bind( &SELECTION_CONDITIONS::sameNetFunc, _1, aAllowUnconnected );
 }
 
 
@@ -100,26 +100,40 @@ SELECTION_CONDITION SELECTION_CONDITIONS::LessThan( int aNumber )
 }
 
 
-bool SELECTION_CONDITIONS::sameNetFunc( const SELECTION& aSelection )
+bool SELECTION_CONDITIONS::sameNetFunc( const SELECTION& aSelection, bool aAllowUnconnected )
 {
     if( aSelection.Empty() )
         return false;
 
-    int netcode = -1;
+    int netcode = -1;   // -1 stands for 'net code is not yet determined'
 
     for( int i = 0; i < aSelection.Size(); ++i )
     {
+        int current_netcode = -1;
+
         const BOARD_CONNECTED_ITEM* item =
             dynamic_cast<const BOARD_CONNECTED_ITEM*>( aSelection.Item<EDA_ITEM>( i ) );
 
-        if( !item )
-            return false;
+        if( item )
+        {
+            current_netcode = item->GetNetCode();
+        }
+        else
+        {
+            if( !aAllowUnconnected )
+                return false;
+            else
+                // if it is not a BOARD_CONNECTED_ITEM, treat it as if there was no net assigned
+                current_netcode = 0;
+        }
+
+        assert( current_netcode >= 0 );
 
         if( netcode < 0 )
         {
-            netcode = item->GetNetCode();
+            netcode = current_netcode;
 
-            if( netcode == NETINFO_LIST::UNCONNECTED )
+            if( netcode == NETINFO_LIST::UNCONNECTED && !aAllowUnconnected )
                 return false;
         }
         else if( netcode != item->GetNetCode() )
diff --git a/pcbnew/tools/selection_conditions.h b/pcbnew/tools/selection_conditions.h
index 715a4fab08..0c508a8971 100644
--- a/pcbnew/tools/selection_conditions.h
+++ b/pcbnew/tools/selection_conditions.h
@@ -76,14 +76,13 @@ public:
 
     /**
      * Function SameNet
-     * Creates a functor that tests if selection contains items belonging to the same net. If there
-     * are items which are not of BOARD_CONNECTED_ITEM type, the result is false. If all items do
-     * not have any net assigned, the result is negative (technically they have the same netcode,
-     * but in most cases they should not be connected together).
-     * @return Functor testing if selected items are exclusively connected items belonging to
-     * the same net (and netcode > 0).
+     * Creates a functor that tests if selection contains items belonging to the same net or are
+     * unconnected if aAllowUnconnected == true.
+     * @param aAllowUnconnected determines if unconnected items (with no net code assigned) should
+     * be treated as connected to the same net.
+     * @return Functor testing if selected items are belonging to the same net.
      */
-    static SELECTION_CONDITION SameNet();
+    static SELECTION_CONDITION SameNet( bool aAllowUnconnected = false );
 
     /**
      * Function SameLayer
@@ -146,7 +145,10 @@ public:
     static SELECTION_CONDITION LessThan( int aNumber );
 
 private:
-    static bool sameNetFunc( const SELECTION& aSelection );
+    ///> Helper function used by SameNet()
+    static bool sameNetFunc( const SELECTION& aSelection, bool aAllowUnconnected );
+
+    ///> Helper function used by SameLayer()
     static bool sameLayerFunc( const SELECTION& aSelection );
 
     ///> Helper function used by HasType()