Occasionally I'm asked to design a small house that will later be expanded into a much larger house. It might be for a growing family, whose needs will change as children come along and get older. Or, as in the two cases illustrated here, it might be a vacation cabin where the owners plan eventually to live year-round. Sometimes the final plan is twice or even three times as large as the original — meaning that a lot of thought has to go into making a practical transition from the small house to the large house. In effect, it's like designing two houses at once — in some ways, two very different houses. Not only must