Vinny, you mentioned he is a pothead... in the mid-70's, it was fairly common for people to lace pot with PCP/Angel Dust, which produces the paranoid/superhuman strength results this guy exhibited.
So even though I don't think anyone has recommended it here, don't even bother with pepper spray.
Steel doors and door frames as a start, and keep 'em locked. Other than that, maybe a few baseball bats sprinkled throughout the house. And a taser or two if you can get your hands on 'em.
Practice your chokehold, too.
Chokehold - Wikipedia, the free encyclopedia