The size of Wainui is approximately 10 square kilometres. It has 5 parks covering nearly 2.9% of total area. The population of Wainui in 2006 was 161 people. By 2011 the population was 328 showing a population growth of 103.7% in the area during that time. The predominant age group in Wainui is 0-9 years. Households in Wainui are primarily couples with children and are likely to be repaying under $300 per month on mortgage repayments. In general, people in Wainui work in a managers occupation. In 2006, 61.1% of the homes in Wainui were owner-occupied compared with 64.3% in 2011.