Kevin and Mary Lloyds' home succumbed to the landslip in May
An urgent investigation is needed into the cause of a landslip threatening cliff-top homes near Scarborough, councillors have heard.
So far three properties have had to be demolished because of the landslip at Knipe Point, overlooking Cayton Bay.
Scarborough Borough Council's cabinet approved a study into the cause of the landslip on Tuesday, so "possible remedial measures" could be identified.
The Environment Agency has agreed to a £126,000 grant to fund the study.
A report to the cabinet said 56 bungalows at Knipe Point, all worth about £150,000, were at risk.
The A165 Filey Road is also threatened by the landslip in the longer term, councillors will hear.
The report said: "The causes and mechanisms of the landslide are currently undetermined but possibly involve a combination of coastal erosion at the toe of Cayton Cliff and excess groundwater within the cliffs.
"As a result, a site investigation is urgently required."