It looks like homes are growing in square footage as the residential market continues to steadily improve. Not only are high-end and custom homes getting bigger, additions to existing homes are becoming more common as well. 

As consumer confidence continues to improve, business conditions at residential architecture firms are reaching their highest levels since the economic downturn, according to the American Institute of Architects. 

"We've seen over the past few years, an increased interest in seamlessly blending indoor and outdoor spaces and building in more informal spaces into homes," said AIA Chief Economist Kermit Baker.

He added, "Because lot sizes don’t show any signs of increasing, it’s clear that homeowners want to maximize their current square footage to its highest potential, as opposed to increasing it."