Seperation Anxiety .... chewing on the door.

I think my dog is experiencing Separation Anxiety .
Whenever we go out he tarts chewing on the door and it gets worst every time we leave him at home.I am at home all day and we try to take him everywhere possible .
But sometimes when we have to leave him at home he chews on the door molding.
I have kept chew toys, chew treats , his chew bones etc etc nothing seems to work .
My hubby looses it everytime he sees it getting worst .
Ben is an adorable dog with the sweetest temperament .
I would hate to tie him up when we go out .
Has anybody else experienced this , how do I get him to stop .
Thanks