When measured against each other in terms of their impact on the environment, an apartment in a multi-dwelling building wins hands down when compared to a single-family house.

A US Energy Information Administration survey found households living in apartment buildings with more than five units used around half the energy as single-family houses.

While it found apartments used less energy given their smaller living spaces and reduced exposure to exterior temperatures, it was found apartments had made the biggest energy efficiency gains compared to houses in recent decades.

“As recent new construction joins the housing stock and older buildings fall out, energy per household in large apartment buildings likely will continue to decline,” noted the survey.

The renowned urban studies professor Richard Florida observed: “Denser settlement patterns yield energy savings; apartment buildings, for example, are more efficient to heat and cool than detached suburban houses.”

Green Star push

Not only do apartments use less energy and water but they are less carbon intensive to construct compared to a house.

One study found the construction of a 200 unit apartment building had 55 tonnes of embodied carbon associated with the materials and construction of each dwelling, compared to 74 tonnes for a single-family home.

All of these benefits do not factor in other environmental benefits of apartments, such as reducing urban sprawl and car dependence (which results in even more transport related emissions).

In Australia, further efficiency gains are being driven by developers including Deicorp, who are seeking to build and design more sustainable apartment buildings. For example, Deicorp’s Hills Showgrounds Village and Highline Westmead projects are both targeting a 5 Green Star building certification, which demonstrates a high environmental performer on a range of criteria including net zero energy consumption, responsible construction, noise levels, access to amenity, light quality and water use.

It saves to be green

Being energy and water efficient also means lower costs for residents.

In addition to using less energy than houses, Green Star apartments, on average, use 66 percent less energy and 51 percent less water than standard apartments, meaning significantly lower utility bills.

And while reducing costs, there is the added value energy and water efficient homes attract.

One Australian study found apartments with a 5 Star Green Rating or higher attracted a price premium of up to 35 percent compared to those with lower energy ratings.