diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/planner/entities/ResourceAllocation.java b/navalplanner-business/src/main/java/org/navalplanner/business/planner/entities/ResourceAllocation.java
index 47ada555d..2d6061e26 100644
--- a/navalplanner-business/src/main/java/org/navalplanner/business/planner/entities/ResourceAllocation.java
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/planner/entities/ResourceAllocation.java
@@ -37,6 +37,7 @@ import org.hibernate.validator.NotNull;
 import org.joda.time.LocalDate;
 import org.navalplanner.business.calendars.entities.AvailabilityTimeLine;
 import org.navalplanner.business.calendars.entities.BaseCalendar;
+import org.navalplanner.business.calendars.entities.CombinedWorkHours;
 import org.navalplanner.business.calendars.entities.IWorkHours;
 import org.navalplanner.business.calendars.entities.SameWorkHoursEveryDay;
 import org.navalplanner.business.calendars.entities.ThereAreHoursOnWorkHoursCalculator;
@@ -214,8 +215,7 @@ public abstract class ResourceAllocation<T extends DayAssignment> extends
                         LocalDate start,
                         ResourcesPerDayModification resourcesPerDayModification,
                         int hoursToAllocate) {
-                    IWorkHours workHoursPerDay = resourcesPerDayModification
-                            .getBeingModified().getWorkHoursPerDay();
+                    IWorkHours workHoursPerDay = getWorkHoursPerDay(resourcesPerDayModification);
                     ResourcesPerDay resourcesPerDay = resourcesPerDayModification
                             .getGoal();
                     AvailabilityTimeLine availability = resourcesPerDayModification
@@ -225,6 +225,14 @@ public abstract class ResourceAllocation<T extends DayAssignment> extends
                             resourcesPerDay, hoursToAllocate);
                 }
 
+                private CombinedWorkHours getWorkHoursPerDay(
+                        ResourcesPerDayModification resourcesPerDayModification) {
+                    return CombinedWorkHours.minOf(resourcesPerDayModification
+                            .getBeingModified().getTaskWorkHours(),
+                            resourcesPerDayModification
+                                    .getResourcesWorkHoursPerDay());
+                }
+
                 @Override
                 protected void markUnsatisfied(ResourceAllocation<?> allocation) {
                     allocation.markAsUnsatisfied();
@@ -566,10 +574,10 @@ public abstract class ResourceAllocation<T extends DayAssignment> extends
     }
 
     private IWorkHours getWorkHoursPerDay() {
-        return getWorkHoursGivenTaskHours(getTaskWorkHoursLimit());
+        return getWorkHoursGivenTaskHours(getTaskWorkHours());
     }
 
-    private IWorkHours getTaskWorkHoursLimit() {
+    private IWorkHours getTaskWorkHours() {
         return new IWorkHours() {
             @Override
             public Integer getCapacityAt(LocalDate day) {
diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/planner/entities/allocationalgorithms/ResourcesPerDayModification.java b/navalplanner-business/src/main/java/org/navalplanner/business/planner/entities/allocationalgorithms/ResourcesPerDayModification.java
index 8d7cef4e1..78b536709 100644
--- a/navalplanner-business/src/main/java/org/navalplanner/business/planner/entities/allocationalgorithms/ResourcesPerDayModification.java
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/planner/entities/allocationalgorithms/ResourcesPerDayModification.java
@@ -28,6 +28,10 @@ import java.util.List;
 import org.apache.commons.lang.Validate;
 import org.joda.time.LocalDate;
 import org.navalplanner.business.calendars.entities.AvailabilityTimeLine;
+import org.navalplanner.business.calendars.entities.CombinedWorkHours;
+import org.navalplanner.business.calendars.entities.IWorkHours;
+import org.navalplanner.business.calendars.entities.ResourceCalendar;
+import org.navalplanner.business.calendars.entities.SameWorkHoursEveryDay;
 import org.navalplanner.business.planner.entities.AvailabilityCalculator;
 import org.navalplanner.business.planner.entities.DayAssignment;
 import org.navalplanner.business.planner.entities.GenericResourceAllocation;
@@ -79,6 +83,19 @@ public abstract class ResourcesPerDayModification extends
                             .getCriterions(), getResources());
         }
 
+        @Override
+        public IWorkHours getResourcesWorkHoursPerDay() {
+            return CombinedWorkHours.maxOf(resourcesWorkHours());
+        }
+
+        private List<IWorkHours> resourcesWorkHours() {
+            List<IWorkHours> workHours = new ArrayList<IWorkHours>();
+            for (Resource each : getResources()) {
+                workHours.add(workHoursFor(each));
+            }
+            return workHours;
+        }
+
     }
 
     private static class OnSpecificAllocation extends
@@ -120,6 +137,12 @@ public abstract class ResourcesPerDayModification extends
         private Resource getAssociatedResource() {
             return getResources().get(0);
         }
+
+        @Override
+        public IWorkHours getResourcesWorkHoursPerDay() {
+            return workHoursFor(getAssociatedResource());
+        }
+
     }
 
     public static ResourcesPerDayModification create(
@@ -159,6 +182,12 @@ public abstract class ResourcesPerDayModification extends
         return result;
     }
 
+    protected static IWorkHours workHoursFor(Resource associatedResource) {
+        ResourceCalendar calendar = associatedResource.getCalendar();
+        return calendar != null ? calendar : SameWorkHoursEveryDay
+                .getDefaultWorkingDay();
+    }
+
     private final ResourcesPerDay goal;
 
     private ResourcesPerDayModification(
@@ -173,6 +202,8 @@ public abstract class ResourcesPerDayModification extends
         return goal;
     }
 
+    public abstract IWorkHours getResourcesWorkHoursPerDay();
+
     public abstract void applyAllocationOnAllTaskLength();
 
     public abstract void applyAllocationUntil(LocalDate endExclusive);
@@ -182,4 +213,5 @@ public abstract class ResourcesPerDayModification extends
 
     public abstract AvailabilityTimeLine getAvailability();
 
+
 }