koreanfestivals1-10, Exercise 2: Hanok

Model answer:

Features (any two): ondol (floor heating); daecheong (cool wooden-floor hall); tiled roofs (giwa); hanji paper windows and doors; regional layouts (square in the north, L-shaped in the centre, open and in a line in the south); baesanimsu siting (mountain behind, river in front).

The word: first seen in a paper of 23 April 1907, when jooga and jaetaek were more common; in a Korean dictionary in 1975, defined as the opposite of "western house".
Why many disappeared: after the Korean War several hanok of historical value were demolished, and after the 1970s apartments and terraced houses were built and many hanok were demolished.

Why the praise is treated as the article's view: the claims that hanok are environment-friendly, pollution-free and that early heating and cooling are still effective read as advocacy; I saw no sources for them.

Sources: Wikipedia, Hanok.