Critics say the ''minimum documentation requirements for building approval lodgement class 1 and 10 residential construction'' were developed without industry consultation, demonstrate a lack of knowledge of home design and building, and were fast-tracked for reasons of political expediency.

The claims were rejected by Craig Simmons, director of construction services at the Environment and Sustainable Development Directorate, who said some of the allegations were ''mischief making'' and the individuals making them would have had their questions answered if they had attended two recent briefing sessions conducted by his department.

Mr Simmons told Fairfax Media the directorate was addressing a serious problem that placed future home owners at risk and said the requirements were subject to review after three months.

Jerry Howard, deputy director of the ACT branch of the Master Builders Association, said the directorate missed a ''perfect opportunity'' to get documentation requirements for building plans right. ''Instead, they have rushed the job, and as a result designers and certifiers now have to generate more paperwork, much of which is not relevant.''

Mr Howard, who has raised his concerns in a letter to the directorate, said there was no doubt there had been problems with building design and certification in the ACT.

''We [the association] have always supported the need for better quality documentation,'' he said. ''But what we have always sought are relevant, quality and appropriate documentation standards.''

Mr Howard, individual designers and builders and Building Design Australia ACT and region branch president, Adam Hobill, say much of the information being demanded by directorate is just not available so early in the process of getting a building approved. ''There appears to be an obvious lack of understanding of the process that goes on,'' Mr Hobill said.

Mr Simmons said certifiers were being asked to supply only the documentation they had at the time the application was being made. ''The job of the certifier is to certify the design is adequate to build the building,'' he said. ''If the certifier does not have the truss specification they are not required to supply it at that stage.''

He said there had been instances of certifiers passing designs that did not include the physical dimensions of the build or in which the proposed floor plan was at odds with what was shown on the elevation.

''We want to make sure what is built corresponds to what is on the plan,'' he said. ''The ACT Supreme Court, as recently as July 19, reiterated certifiers should not 'uncritically accept' whatever is put in front of them. We haven't taken a baseball bat to them [designers and certifiers], we've given them a couple of months.''

Designers and certifiers have also questioned why a design problem was being handled through additional conditions on building certifiers.

Mr Simmons said the reason was simple; under the law as it stands the directorate does not have regulatory oversight over designers and engineers. The new requirements are an interim arrangement to put consumer protections in place until such oversight takes effect next year. Once it is in place, the directorate will be able to regulate engineers and designers directly.