Luxury apartments under construction in Brooklyn Bridge Park in New York. Michael Appleton for The New York Times

Apartment units make up the lions’ share of the recent increased activity in the housing industry. Though this article does not go into much of the back-story on why this trend is taking place, many of the comments it has drawn are from those who seem to understand. Single-family home building is on the decline compared to multi-family housing for many reasons, most of which are under the umbrella of sustainability. Energy and material conservation, compact urban development supporting public transit, social and economic benefits of urban lifestyles, and preserving agricultural land and the earth’s ecology come to mind. Apartment construction does not contribute as much, per unit, to the economy, so potentially slower (more steady?) growth of the economy may be a result.

Add it all up, and traditional, suburban stand-alone houses — and the construction of them — appear poised to play a smaller role in the economy, and Americans’ living situations, for some time to come

A version of this article appears in print on May 17, 2014, on page B2 of the New York edition with the headline: Housing Is Recovering. Single-Family Homes Aren’t.