diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/GanttPanel.java b/ganttzk/src/main/java/org/zkoss/ganttz/GanttPanel.java
index d6534bec1..bcaeb2d39 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/GanttPanel.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/GanttPanel.java
@@ -196,7 +196,7 @@ public class GanttPanel extends XulElement implements AfterCompose {
     }
 
     public void adjustZoomColumnsHeight() {
-      response("adjust_height", new AuInvoke(this, "adjust_height"));
+        response("adjust_dimensions", new AuInvoke(this, "adjust_dimensions"));
     }
 
     public LocalDate getPreviousStart() {
diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/Planner.java b/ganttzk/src/main/java/org/zkoss/ganttz/Planner.java
index f86c1526e..f4f82ca88 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/Planner.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/Planner.java
@@ -791,6 +791,7 @@ public class Planner extends HtmlMacroComponent  {
             setTaskListPredicate(predicate);
         }
         isFlattenTree = !isFlattenTree;
+        Clients.evalJavaScript("ganttz.Planner.getInstance().adjustScrollableDimensions()");
     }
 
     public FilterAndParentExpandedPredicates getPredicate() {
diff --git a/ganttzk/src/main/java/org/zkoss/ganttz/TaskList.java b/ganttzk/src/main/java/org/zkoss/ganttz/TaskList.java
index f801ec5a0..4be2dfe80 100644
--- a/ganttzk/src/main/java/org/zkoss/ganttz/TaskList.java
+++ b/ganttzk/src/main/java/org/zkoss/ganttz/TaskList.java
@@ -61,8 +61,6 @@ import org.zkoss.zul.impl.XulElement;
  */
 public class TaskList extends XulElement implements AfterCompose {
 
-    private static final int HEIGHT_PER_ROW = 20; /* 30 */
-
     private transient IZoomLevelChangedListener zoomLevelChangedListener;
 
     private List<Task> currentTotalTasks;
@@ -142,7 +140,6 @@ public class TaskList extends XulElement implements AfterCompose {
         addListenerForTaskComponentEditForm(taskComponent);
         taskComponent.afterCompose();
         if (relocate) {
-            setHeight(getHeight());// forcing smart update
             getGanttPanel().adjustZoomColumnsHeight();
             getGanttPanel().getDependencyList().redrawDependencies();
         }
@@ -189,11 +186,6 @@ public class TaskList extends XulElement implements AfterCompose {
         taskComponent.setContext(getContextMenuFor(taskComponent));
     }
 
-    @Override
-    public String getHeight() {
-        return getTasksNumber() * HEIGHT_PER_ROW + "px";
-    }
-
     private TimeTrackerComponent getTimeTrackerComponent() {
         return getGanttPanel().getTimeTrackerComponent();
     }
diff --git a/ganttzk/src/main/resources/web/js/ganttz/GanttPanel.js b/ganttzk/src/main/resources/web/js/ganttz/GanttPanel.js
index 97800b9f4..1ac8d09d0 100644
--- a/ganttzk/src/main/resources/web/js/ganttz/GanttPanel.js
+++ b/ganttzk/src/main/resources/web/js/ganttz/GanttPanel.js
@@ -33,8 +33,7 @@ ganttz.GanttPanel = zk.$extends(zk.Widget,{
             jq(element).css("left", "-" + this._rightpannellayout.scrollLeft() + "px")
             }, this));
     },
-    adjust_height : function(){
-        jq(this.$n()).height(jq('#scroll_container').height());
+    adjust_dimensions : function(){
         ganttz.Planner.getInstance().adjustScrollableDimensions();
     },
     _calcXY : function(event){
diff --git a/ganttzk/src/main/resources/web/js/ganttz/Planner.js b/ganttzk/src/main/resources/web/js/ganttz/Planner.js
index d8b399b0d..ed6eab6f0 100644
--- a/ganttzk/src/main/resources/web/js/ganttz/Planner.js
+++ b/ganttzk/src/main/resources/web/js/ganttz/Planner.js
@@ -35,19 +35,9 @@ ganttz.Planner = zk.$extends(zk.Macro,{
         DOMTimetracker.width(DOMScrollContainer.innerWidth());
         DOMTimetracker.height(
                 Math.max(
-                        jq(window).height() -
-                        this.$class.TIMETRACKER_OFFSET_TOP +
-                        26),
-                        (
-                        jq('#listdetails_container').height() +
-                        12));
-
-        DOMScrollContainer.height(
-                jq(window).height() -
-                this.$class.TIMETRACKER_OFFSET_TOP -
-                this.$class.FOOTER_HEIGHT +
-                this.$class.SCROLLBAR_WIDTH * 2);
-
+                         jq(window).height() - this.$class.UNSCROLLABLE_AREA,
+                         jq('#scroll_container').height() + this.$class.BOTTOM_WATERMARK_PADDING
+                    ));
 
         // Inner divs need recalculation to adjust to new scroll displacement lenght
         ganttz.GanttPanel.getInstance().reScrollY(jq('#listdetails_container').height());
@@ -61,15 +51,14 @@ ganttz.Planner = zk.$extends(zk.Macro,{
         zAu.send(new zk.Event(this, 'onZoomLevelChange', {zoomindex : zoomindex, scrollLeft : scrollLeft}));
     }
 },{
-    FOOTER_HEIGHT : 40, // Design-relative footer height
-    TIMETRACKER_OFFSET_TOP : 120,   // Design-relative height above timetracker
-    TASKDETAILS_WIDTH : 300, // Taskdetails column fixed width (300)
-    TASKDETAILS_HEIGHT : 180, // 260 // Design-relative reservated height for taskdetails (300,260)
-    SCROLLBAR_WIDTH : 15, // Scrollbars default width
+    TASKDETAILS_WIDTH : 300,        // Taskdetails column fixed width (300)
+    UNSCROLLABLE_AREA : 170,       // Design-relative reservated height for taskdetails (300,260)
+    SCROLLBAR_WIDTH : 15,           // Scrollbars default width
+    BOTTOM_WATERMARK_PADDING : 40,  // Space left behind last task
     getInstance : function(){
         return this._instance;
     },
     setInstance : function(instance){
         this._instance = instance;
     }
-})
\ No newline at end of file
+})