Demdyke Row was a row of cottages in Beckindale. It was the home of a few Beckindale residents who lived in each of the 6 cottages including Percy Edgar until his death in 1976, Joe Sugden in the 1970s and Seth and Meg Armstrong from 1952 until the row was destroyed in the plane crash in 1993.
Demdyke Row was hit by wreckage from the plane in the plane crash in December 1993 and the bit that was destroyed was never rebuilt, however it is strongly possible that Tall Trees, at the back of the village is the remainder of Demdyke Row. This has never been confirmed in the show but has been hinted at. (The Emmerdale archivist said that Demdyke was fully destroyed in the crash and Tall Trees is another building).