Your description of building materials is exactly why when thinking of home defense, penetration is of vital importance. Even if you are in a single family home, the penetration of various firearms needs to be a real consideration.
As to the OP's conclusion regarding the AK47, I wouldn't consider any rifle a good choice for home defense, and I'm wary of many pistols. Stopping an assailant at the cost of involuntary manslaughter of neighbor seems like a very bad deal, especially when other better options exist.
I understand those who rely on the easy access of handgun that is easier to access, and there is somewhat less danger of wall penetration. Still, I'll rely on my 12 gauge for home defense where takedown is nearly guaranteed and the chance of neighbor'cide is nearly non-existant.
Also, I've got a security system and a dog, so even a determined attacker has a couple of things to consider/contend-with while I fetch my shotgun.
Last edited by Herluf; September 24, 2013 at 07:20 PM.