diff --git a/navalplanner-business/src/main/java/org/navalplanner/business/calendars/entities/CalendarException.java b/navalplanner-business/src/main/java/org/navalplanner/business/calendars/entities/CalendarException.java
index 2d43d2177..1abff1058 100644
--- a/navalplanner-business/src/main/java/org/navalplanner/business/calendars/entities/CalendarException.java
+++ b/navalplanner-business/src/main/java/org/navalplanner/business/calendars/entities/CalendarException.java
@@ -78,7 +78,7 @@ public class CalendarException extends BaseEntity {
     }
 
     public Integer getHours() {
-        return hours;
+        return hours != null ? hours : 0;
     }
 
     public CalendarExceptionType getType() {