Housing New Zealand says it has tripled the amount of money spent on consultants, such as architects and engineers, in the past five years because of major projects, including the Christchurch recovery.
The Labour Party says Housing New Zealand has cut more than 100 staff while tripling its spending on consultants since 2008.
It says that, coupled with the closure of front line offices and the introduction of an 0800 number, is the cause of problems for state house tenants, who have complained of tardy and shoddy maintenance work.
Labour's Housing spokesperson, Phil Twyford, says in the past two years, 21 Housing New Zealand offices have closed around the country.
He says the total number of permanent Housing New Zealand staff has reduced from 1,033 to 921 - a reduction of 112.
Other figures, supplied by Housing New Zealand, show the Government-owned company spent $54 million on consultants in the year to June 2012, up 213% on the figure for the year to June 2008.
In 2007/08 the consultancy spend was $17.3m, in 2008/09 $25.248m, in 2009/10 $27.362m, in 2010/11 $33.854m, and in 2011/12 $54.178m.
Housing New Zealand employed 297 outside contractors in the year to June 2012, up from 214 in the previous year.
A total of $1.1. million was spent on redundancy payments, 263% higher than the figure four years earlier.
Mr Twyford says the restructure needs to be reviewed because the current model is inefficient.
He says Housing New Zealand has taken resources away from people working on the frontline with institutional knowledge, which is a really dumb and inefficient way to run an agency.
Housing New Zealand acting chief executive Kay Read says more money has been spent because of two major projects - the Christchurch recovery, and the national transformation programme.
"These are specialist people - designers, architects, engineers ... the systems people who know about the new system that we've brought in. Those are the types of expertise that we've bought into the business."
Ms Read says if tenants are not getting their problems resolved quickly through the 0800 line they should escalate the query to the team leader or manager.