If the zoning wasn't regulated to benefit existing owners then apartments would be built, plus new townhouses, and these damp decaying places would be $100 a week. If there was an actual housing/rental market (you know, one with real competition, instead of a market that's propped up by government policy) that could work, but I'm not against insulation requirements. If they sent jackboot thugs to inspect homes and threatened to shut them down if landlords didn't comply, I'd fully support it.