An Bord Pleanala has refused planning permission for 452 build-to-rent apartments in eight blocks at Cornelscourt village in south Dublin.
Dun Laoghaire-Rathdown County Council and locals had opposed Cornel Living Ltd's plan to construct the blocks - including one 12 storeys high - in Old Bray Road, Dublin 18.
The proposed development, which is next to the N11, also included 10 semi-detached homes and six bungalows along with a cafe/restaurant.
In total, more than 80 objections were lodged, with the Foxrock South Residents Association and the Grange Castle and Foxrock Wood Residents Association among those opposing the plans.
Former Fine Gael TD Mary Mitchell O'Connor added her voice to the bid to stop the development from proceeding.
Now, the appeals board has refused planning permission after concluding that the proposals fail to provide an adequate level of residential amenity for future occupants.
It found that the level of communal open space and the proportion of apartments with windows on one wall only were below the minimum standards set out in ministerial guidelines.
An Bord Pleanala also said the proposed development would be premature because of existing deficiencies in the wastewater sewerage network.
Its grounds for refusal echo some of the objections put forward by the county council.
The council said planning should be refused due to the deficient quality and quantity of public/communal space.
It was also critical of the inadequate amount of dual-aspect apartments in the scheme.
When lodging her submission, TD Ms Mitchell O'Connor told An Bord Pleanala: "The vast majority of the units will be accommodated in eight massive apartment blocks. The height and scale bear no relationship to the adjacent homes".
She further contended that "the entire development being built for rental is a matter of some concern. Rentals on this scale attract transient populations and add nothing to the local community".
Ms Mitchell O'Connor stated that she fully supported appropriate development "but agrees with the residents that the development proposed in this application has too many flaws to be appropriate for the area".