It's something I wonder about quite a bit.
Say the zombie apocalypse is here. For whatever reason you can't leave your house with your bug out bag so you need to batten down the hatches and stay put. How suitable a stronghold would your house be?
I'm quietly confident about mine. It's a back to back terrace so no nasty surprises from the rear oo-er. The front yard is small but has a high wrought iron fence on top of a brick wall. Gate is high too and if i got a bike lock I think I'd be ok. If they did breach the yard windows are again quite high, some have bars on and our door is quite sturdy.
Final stand would be in the old coal cellar or the converted attic.
We have one spare room if anyone needs it btw.