The proposed Spencer Dock development would have profound and negative impacts on the city skyline and on important views and vistas, particularly the "Georgian mile", the planning hearing was told yesterday.
Mr Conor Norton, a planner with Dublin Corporation, said that along the Georgian mile from Leeson Street to Merrion Square any development higher than 40 metres would protrude above Holles Street Hospital, which formed the end of the vista.
It would be seen above the roofline of the hospital and would be an intrusion.
"We believe it is inconsistent with maintaining the integrity of the vista," Mr Norton said.
In the Dublin City Planning Officer's report on Spencer Dock and the National Conference Centre, Mr Norton said the middle ground would also be profoundly affected.
"The development appears large and bulky on the skyline. The development would contrast greatly in scale with the adjacent development. Landmarks in the middle ground and background would be obscured or intruded on," he said.
Answering questions from the Bord Pleanala inspectors, Mr Norton said the vista along the Georgian mile was intact as it was. Breaking the silhouette in any way would reduce the quality of the space.
He said there was a potential for a landmark building on the site but he believed it should be the National Conference Centre itself. He was generally happy with it, as it was an important civic building.
In terms of the time scale, he had said he thought the development should be adaptable to meet the changing market, possibly by being split into blocks capable of developmental independence.
Diagrams suggested that the existing canal space would be overshadowed by the National Conference Centre, and this was a concern, Mr Norton said.
The Dublin city architect, Mr Jim Barrett, said visually the development had excessive bulk and a myriad of very large buildings which overshadowed open spaces.
Referring to residential properties within the development, Mr Barrett said the number of children and families coming into the city had been minuscule, "and the new proposed apartments are not conducive to family living."
Of the development generally, he said: "The planning authority was confronted with a scheme which did not have any coherent architectural language."
In terms of square feet, he believed 4.6 million was the maximum the site should take.
One of the emotive issues was that of height in the centre of the complex, and whether there should be a limitation of 54 metres on all the buildings. He considered there was a risk that if such a cap was recommended, all developments would go up to that and result in a banal skyline.
"A much taller, slender building could be an option," he suggested. Questioned further about this, Mr Barrett replied that an independent architect should have flexibility.
"I feel that an elegant building in the distance from the Georgian mile would not undermine the integrity of the vista." It was not so much a matter of something protruding on to the skyline as what it would look like - if it was ugly or elegant.