The design of Scottish blackhouses originated several thousand years ago, consisting of a twin-walled building that had a layer of insulating peat in the gap between the stone walls. This design proved resistant to Scotland's west coast weather and was unrivalled until a new design (named 'white houses') arrived which separated the living quarters between animals and people. As modern building techniques were brought onto the islands the traditional blackhouses fell out of favour and most of them were abandoned by the early 1900s. The last permanent residents of Scottish blackhouses finally moved out for good in the 1980s. Today, many of the old buildings have been renovated and are now used as holiday accommodation.