Change is scary. And it's all around us in the world of Howards End, which, as you might imagine, makes said world kind of a scary place. It's funny – while a lot of the novel is concerned with the coziness of domestic life and the comforting beauties of the English countryside, the rest of it is filled with a definite sense of menace; though there are things in everyday life that make living worthwhile, like a freshly-mown field or a leisurely lunch, we get the feeling that all of these things are somehow endangered by the social, economic, political, and even geographical changes facing the world Forster presents. England is faced with urbanization and modernity, and in the moment of the novel, it's about to fall off a precipice into a whole new era.
Change (whether economic, geographical, or social) is overwhelmingly viewed as a negative quantity in Howards End, since it heralds the increasing isolation of individual human beings.
Two models of change are posed in Howards End: the first, the idea that change is inexorable and inevitable, is negative, while the second, in which the tide of civilization will someday return and undo itself, offers a kind of hope for the future. The end of the novel is unclear as to which model will ultimately rule.