A nine-house holiday home development in the west Kerry Gaeltacht village of Ballydavid/ Baile na Gall has been refused planning permission by An Bord Pleanála, in part because it would dilute the Irish language and culture of the area.
The decision is likely to impact on other small holiday home developments for Kerry's two Gaeltachta on the peninsulas of Iveragh and Dingle.
Until now holiday home developers of up to eight houses thought they could escape language clauses as their population would be transient.
Kerry County Council had granted permission for eight out of the nine holiday homes applied for on an elevated site at Ballydavid without any reference to the Irish language, and the council had not asked for a linguistic impact assessment.
However, those who appealed the decision said the small historic village near Smerwick Harbour was already overdeveloped by holiday homes.
In fact only one in three of the existing houses in the village were family homes. They also said the holiday home development would weaken the language.
Údarás na Gaeltachta, which also appealed the decision, said recognition was not given to the language implications of the proposed development by the local authority, and "adequate recognition for the language and Gaelic culture is required under the Planning and Development Act, 2000".
"Practical steps are required of local authorities in Gaeltacht areas to assist in the conservation and development of the Irish language," Údarás said.
The report of an inspector from An Bord Pleanála said the holiday home residents would account for half the summer population.
Language clauses would be unworkable in the case of holiday home developments, senior planning inspector James Carroll said.
"While it would be realistic to condition the occupation of permanent residences by Irish speakers, I do not consider that it would be realistic to include such a condition in relation to holiday homes," he said in his report.
In its decision, the board gave six reasons for refusing the development.
These included height and design of buildings, their location in a rural area, the existing high level of holiday homes, inadequate sewerage provision and its location within a Gaeltacht area.
"Having regard to the existing level of holiday homes development within the Ballydavid area, it is considered that the proposed holiday homes would constitute an excessive provision of such development in a manner contrary to the protection of the linguistic and cultural heritage of the Gaeltacht," the board said.