The country's biggest listed property investor has posted a 27 per cent gain in first-half profit and announces further plans to upgrade Sylvia Park.

Profit for Kiwi Property Group was $45.6 million in the six months to the end of September from $36m a year earlier, the Auckland-based company said.

Total income including revenue from property rose 6.7 per cent to $114.8m even after the year-earlier period was bolstered by $5.9m of litigation settlement income.

Kiwi Property expanded its portfolio in the first half, settling its acquisition of 50 per cent of The Base shopping centre in Hamilton while selling Centre Place – South in that city, opening the remaining retail tenancies at its Westgate Lifestyle retail centre in Auckland and starting construction of an office building at its Sylvia Park site.

The company said it will spend $9.1m expanding the dining lane at Sylvia Park and said planning is advanced on creating a “world-class town centre” at the site, with an investment of about $180m in the shopping mall.

“We have grown revenue and increased dividends, while continuing to build a stronger underlying portfolio of property assets,” said chief executive Chris Gudgeon.

In August, the company said it planned to build an $80m office tower by June 2018 to expand Sylvia Park and had signed insurer IAG New Zealand as an anchor tenant.

It said it incurred only minor damage to its buildings following the Nov. 14 earthquake.