New Zealand law changes that will force landlords to insulate their houses and install smoke alarms equate to "putting lipstick on the pig", new home builder Jennian Homes says.

NZ Building and Housing Minister Nick Smith announced the new rules on Thursday, saying they would ensure 180,000 homes were warmer, drier and safer. From July 1 next year, all social housing subsidised by the government will be retrofitted with ceiling and underfloor insulation, and have smoke alarms. From July…