diff --git a/abstract_client.cpp b/abstract_client.cpp
index c073f6ae15..df367a9f80 100644
--- a/abstract_client.cpp
+++ b/abstract_client.cpp
@@ -448,4 +448,14 @@ void AbstractClient::keepInArea(QRect area, bool partial)
         move(tx, ty);
 }
 
+QSize AbstractClient::maxSize() const
+{
+    return rules()->checkMaxSize(QSize(INT_MAX, INT_MAX));
+}
+
+QSize AbstractClient::minSize() const
+{
+    return rules()->checkMinSize(QSize(0, 0));
+}
+
 }
diff --git a/abstract_client.h b/abstract_client.h
index 27eaf9f411..7034d4d4b3 100644
--- a/abstract_client.h
+++ b/abstract_client.h
@@ -131,6 +131,14 @@ class AbstractClient : public Toplevel
      * To read only the caption as provided by WM_NAME, use the getter with an additional @c false value.
      **/
     Q_PROPERTY(QString caption READ caption NOTIFY captionChanged)
+    /**
+     * Minimum size as specified in WM_NORMAL_HINTS
+     **/
+    Q_PROPERTY(QSize minSize READ minSize)
+    /**
+     * Maximum size as specified in WM_NORMAL_HINTS
+     **/
+    Q_PROPERTY(QSize maxSize READ maxSize)
 public:
     virtual ~AbstractClient();
 
@@ -311,6 +319,8 @@ public:
     virtual void resizeWithChecks(int w, int h, ForceGeometry_t force = NormalGeometrySet) = 0;
     void resizeWithChecks(const QSize& s, ForceGeometry_t force = NormalGeometrySet);
     void keepInArea(QRect area, bool partial = false);
+    virtual QSize minSize() const;
+    virtual QSize maxSize() const;
 
     // TODO: remove boolean trap
     static bool belongToSameApplication(const AbstractClient* c1, const AbstractClient* c2, bool active_hack = false);
diff --git a/client.h b/client.h
index f2522494fa..10a5c94a8c 100644
--- a/client.h
+++ b/client.h
@@ -164,14 +164,6 @@ class Client
      * The "Window Tabs" Group this Client belongs to.
      **/
     Q_PROPERTY(KWin::TabGroup* tabGroup READ tabGroup NOTIFY tabGroupChanged SCRIPTABLE false)
-    /**
-     * Minimum size as specified in WM_NORMAL_HINTS
-     **/
-    Q_PROPERTY(QSize minSize READ minSize)
-    /**
-     * Maximum size as specified in WM_NORMAL_HINTS
-     **/
-    Q_PROPERTY(QSize maxSize READ maxSize)
     /**
      * Whether the window has a decoration or not.
      * This property is not allowed to be set by applications themselves.
@@ -229,8 +221,8 @@ public:
 
     bool hasNETSupport() const;
 
-    QSize minSize() const;
-    QSize maxSize() const;
+    QSize minSize() const override;
+    QSize maxSize() const override;
     QSize basicUnit() const;
     virtual QPoint clientPos() const; // Inside of geometry()
     virtual QSize clientSize() const;