An Taisce claims Dublin City Council has cost the taxpayer around €40 million by encouraging high-rise plans, such as the Mater Children's Hospital which was later found to be in breach of its development plan.
The heritage body has made the claim in a submission to Government.
Dublin City Council has rejected the claims, saying it has been vindicated by both an internal departmental review and an independent report.
An Taisce points to the rejection of the Children's Hospital by An Bord Pleanála, saying this alone cost the taxpayer around €30m.
It said minutes of meetings show that the city council officials did not believe that the scale of the project would be rejected by the board who dealt with it as a strategic infrastructure application.
An Taisce also complained about the absence or inadequacy of records kept by the city council in relation to pre-planning meetings, which is required by law.
It has pointed to a total of 25 other high-rise projects, including Liberty Hall and Jury's that were either rejected or modified by An Bord Pleanála.
It calculates the total cost to the taxpayer in dealing with these planning applications to be around €40m.
But Dublin City Council says its position has been vindicated both by an internal review by the Department of the Environment and by independent report by Hendrik van der Kamp.
It says that height policy was not clear in previous development plans and that there are competing interests to be considered when landmark buildings are planned.
It says that An Taisce should withdraw its allegations against the council.
Minister of State for Housing Jan O'Sullivan said that Mr van der Kamp had recommended that a study be conducted into the quality of the planning decisions.
She said she "will look positively" at this suggestion.