Use Hovel as free wall. It's second toughest building after overmind, and has very fast regeneration.
(if I remember correctly, 370 life and 20 regeneration)
Sitting in a hovel is asking for trouble - don't do it. Remember, hovel is available at stage3. Even assuming humans don't level up faster than you, your hovel will be attacked with pulse rifle, grenades, lucifer cannon. Its safer to just hide somewhere.
Hovel could be somewhat useful if it was available on stage2, and/or regenerated granger/nearby grangers.