diff --git a/libreplan-business/src/main/java/org/libreplan/business/planner/entities/TaskElement.java b/libreplan-business/src/main/java/org/libreplan/business/planner/entities/TaskElement.java
index fd9fcba50..52c31d235 100644
--- a/libreplan-business/src/main/java/org/libreplan/business/planner/entities/TaskElement.java
+++ b/libreplan-business/src/main/java/org/libreplan/business/planner/entities/TaskElement.java
@@ -695,6 +695,14 @@ public abstract class TaskElement extends BaseEntity {
         return sumOfHoursAllocated;
     }
 
+    public Integer getSumOfHoursAllocatedCalculated() {
+        int result = 0;
+        for(ResourceAllocation<?> allocation : getAllResourceAllocations()) {
+            result += allocation.getAssignedHours();
+        }
+        return result;
+    }
+
     public String toString() {
         return super.toString() + " :: " + getName();
     }
diff --git a/libreplan-webapp/src/main/java/org/libreplan/web/planner/TaskElementAdapter.java b/libreplan-webapp/src/main/java/org/libreplan/web/planner/TaskElementAdapter.java
index b22323a67..3bfd3a79f 100644
--- a/libreplan-webapp/src/main/java/org/libreplan/web/planner/TaskElementAdapter.java
+++ b/libreplan-webapp/src/main/java/org/libreplan/web/planner/TaskElementAdapter.java
@@ -597,7 +597,13 @@ public class TaskElementAdapter {
             private GanttDate getAdvanceEndDate(BigDecimal advancePercentage) {
                 Integer hours = Integer.valueOf(0);
                 if (taskElement.getOrderElement() != null) {
-                    hours = taskElement.getSumOfHoursAllocated();
+                    if(taskElement.getParent() == null){
+                        //it's an order, we use the cached value
+                        hours = taskElement.getSumOfHoursAllocated();
+                    }
+                    else {
+                        hours = taskElement.getSumOfHoursAllocatedCalculated();
+                    }
                 }
 
                 if (taskElement instanceof TaskGroup) {