The figures show the average consent is now taking 20 working days to process, and one consent blew out to 57 days.
At the same time last year, consents were taking eight days to process and the longest took 21 working days.
Consents are meant to be processed within 20 working days of acceptance.
The Otago Daily Times reported earlier this month delays have caused issues for both large and small building firms, as companies juggled planning around blown-out deadlines.
It was reported some small companies had had to down tools and send workers on leave to cope.
Council building services manager Neil McLeod said the council was taking steps to address the issue, including recruiting more staff, bringing in staff from other councils to help, outsourcing work to other councils and contractors and having council staff working overtime to clear the backlog.
"As the statistics show, at the start of last year the DCC had a very good average processing time,'' Mr McLeod said.
"This has gradually risen over the past year, but only exceeded the statutory 20 working day limit last month.''
The rise was due to a number of factors, he said.
Among them were last year's June floods, when building inspectors were diverted from consent processing to checking homes in flood-affected areas, staff vacancies and illness and a shortage of building consent officers in the Southern region.
The number of consent applications this year had increased about 20%, putting additional strain on stretched resources.
The council's measures were having some effect, he said.
"We are working hard to reduce processing times and have taken a range of measures to address processing delays,'' Mr McLeod said.
"The number of 20-plus day consents are reducing each week and we are aiming to be back within the statutory 20-day processing period by the end of April.''
He had previously said the council sympathised with the frustrations of those in the industry and was working to reduce the issues where possible.
In February, the council issued 193 building consents, a 38.8% increase on the 139 issued in February 2015 and 2014.
However, in January only 102 were issued, down on 122 in January 2015 and 123 in January 2014.
