An Bord Pleanala is considering plans for 700 new build-to-rent apartments on Dublin's southside.
The proposed units are located in Stillorgan, another at The Grange on Brewery Road, and a third at Dundrum Town Centre.
The proposals for the new units bypassed local planners under the new fast-track plans.
The Cathaoirlaeach of Dun Laoghaire Rathdown County Council said two of the three proposals are still up for public consultation.
Shay Brennan thinks 700 build-to-rent units is too many for the area.
He said: "Two of the three cases, they are still open for public consultation. At our meeting, we made strong observations that particularly around the fact that we would be encouraging An Bord Pleanala to consider that putting that many units for rental through, while at the same time not processing any units for sale, is somewhat shortsighted.
"It would be prudent to examine that ratio."