if (document.images)
  {
  preload("houses1","images/houses_off.gif");
  preload("houses2","images/houses_on.gif");
  preload("rooms1","images/rooms_off.gif");
  preload("rooms2","images/rooms_on.gif");
  preload("safety1","images/safety_off.gif");
  preload("safety2","images/safety_on.gif");
  preload("locality1","images/locality_off.gif");
  preload("locality2","images/locality_on.gif");
  preload("contact1","images/contact_off.gif");
  preload("contact2","images/contact_on.gif");
  preload("home1","images/home_off.gif");
  preload("home2","images/home_on.gif");
  preload("bedroom1","images/bedroom_off.gif");
  preload("bedroom2","images/bedroom_on.gif");
  preload("bathroom1","images/bathroom_off.gif");
  preload("bathroom2","images/bathroom_on.gif");
  preload("kitchen1","images/kitchen_off.gif");
  preload("kitchen2","images/kitchen_on.gif");
  }