Design Matters
This exhibit from the National Association of Home Builders is now 3-years old. At the time of this survey, 60-84% of demand was for some sort of open-floor design; the trend has surely increased since then from my experience of appraising new construction and remodeled homes.
The trend for open-floor living resides in cultural and life-style changes. NAHB does in depth studies using demographic research in addition to surveys. Home buyers are getting younger, they work a ton, and their domestic relations are quite a contrast of what they were in the mid-century. A lifestyle that is fast paced, multi-tasked, needs efficiency which is what an open-floor plan has to offer. Cook, entertain, within view of the flat screen; look over your kids or dogs, all at once and all from the kitchen.