Auckland's Jessop Architects has developed plans for passive houses with extremely low energy consumption.
Darren Jessop said he wants to raise awareness about the concept and a $160,000 Titirangi house, about to be built, was a good example, he said.
"It's a 24sq m one-bedroom crib-style retreat, with a bathroom and kitchen and it's how to get all the main functions into one small space, and make it low energy," he said.
The small place in a cool bush setting was for a client who wanted a retreat from the bustle of the city.
Passive houses are well insulated and virtually airtight and the main form of heating is via passive gain.