The scheme was for a proposed extension to a garage to create a one-bedroom holiday let annex, at Wellfield Gardens, Alnmouth.
Planning officers had recommended approval, despite objections from the parish council and residents, who had raised concerns about the impact it would have on amenity and that the village already has too many holiday homes.
At last Thursday’s planning meeting, councillors sided with objectors and voted to turn down the application, going against officer advice.
Alnwick councillor Robbie Moore said: “The impact on neighbouring dwellings is far greater than what the planning officer concludes it is.”
His colleague Coun Gordon Castle added: “It is a very tight squeeze in that location and will impact on amenity – it is a step too far.”
Earlier, parish-council chairman Shaun Whyte said that a recent study had shown that of all the privately-owned properties in the village, almost 50 per cent are second homes and holiday lets.
Speaking for the development, the applicant’s wife, Emma Willcox, said that the holiday let wouldn’t overshadow adjacent properties and would provide valuable tourist accommodation, which in turn would help to support business and employment.
Nine councillors voted against the application, with one abstention.