The ACT government has conceded its rules for overseeing building quality have failed to prevent examples of "serious non-compliance" during construction of new developments.
The admission comes as the government acknowledges it has yet to fully implement reforms designed to increase scrutiny of building work, more than two years after they were promised.
In the ACT, work sites have to be supervised by licensed builders, and subjected to inspections from certifiers at different stages of construction.
In its submission to the ACT Assembly's building quality inquiry, the government has acknowledged the regulations had generally failed to prevent poor construction work.
"While these mechanisms have been effective in managing some problems, the government has acknowledged that overall, these mechanisms have not been operating to prevent serious non-compliance with building laws and approvals," the submission stated.
Concerns about a lack of independent oversight and scrutiny during the construction and certification phase have been a common theme in feedback to the building quality inquiry, which has now received 100 submissions.
A number of submissions have detailed examples of buildings which have been completed and certified, despite design elements varying from approved development plans.
Access Canberra received 753 building-related complaints last financial year, up from 166 in 2016-17 and 177 in 2015-16. More than 300 of the complaints lodged in 2017-18 reported issues of non-compliant work.
The government has long been aware of concerns about lax regulation of construction, and in 2015 flagged a stricter oversight regime as part of a wider overhaul of rules.
The 2015 review recommended three measures for on-site supervision and site inspections: Guidelines for builders and "critical hold points" during construction; clarifying the role of certifiers; and requiring inspection information to be provided shortly after it was complete.
The review recommended the "short-term reforms" be introduced by the end of 2016. The wider reform package, which included 43 recommendations targeting various aspects of the industry, was slated for implementation by the end of 2017-18. At the time, the Barr government promised to deliver the reforms in that timeframe.
This week, an ACT government spokeswoman said the three reforms targeting building-quality compliance were scheduled to be fully implemented this financial year. The remaining changes were due to be finalised by the end of 2019-2020, she said.
The spokeswoman would not comment on the reasons for the delay. Nor would she provide examples of "serious non-compliance" at Canberra construction sites.
In its submission to the inquiry, the government said the new rules were intended to "improve the operation and understanding of the inspection process, increase competency and supervision of building practitioners and provide additional regulatory oversight with more oversight and inspection during construction".
The submission noted that while the reforms were developed in response to specific community concerns about the quality of new apartments, the territory's regulatory regime would need to nimble enough to address issues relating to all types of buildings.
The spokeswoman said the ACT's Minister for Building Quality Improvement, Gordan Ramsay, would provide an update on the progress of the reform package later this month.