This is an enjoyable little horror movie and more a kin to the movies I watched growing up (horror with a lowercase h by todays standards) The film has a nice long run up to the action which gives you a chance to get to know the characters (which are fairly bland but that doesn't matter) A lot of the horror is creepy crawly based which is more disturbing that scary.
The characters act out in fairly realistic ways (no one pops up to the attic on their own to investigate that damn scratching noise) and there is a real sense of peril.
Don't expect big affects, gore, nudity, over the top action or paralysing fear. Do expect to see an intelligent movie based on a not so intelligent premises, well executed in good time.