According to the Census Bureau, houses across the nation are steadily getting bigger. The average house built in 2013 was 2,600 square feet, up from 2,521 square feet in 2007.

Still, the tiny house movement — which promotes the use of dwellings as small as 200 square feet — is gaining momentum across the country. Many see them as a way to promote housing that is more affordable and more sustainable in creating a smaller environmental footprint.

Now a Maryland nonprofit called SustainaFest is pushing the movement by offering potential homeowners an opportunity to win a 210-square-foot dwelling through its Tiny House Contest.

The hyper energy-efficient house was built by middle and high school students in Maryland as part of the group’s Student Sustainability Lab.

In 2014, students from around the state participated in a project with educators, professionals and military veterans to build an award-winning tiny house. Since then, the house, which is mobile, has been on a statewide tour of home shows, green expos and schools.

To enter, you must pay a fee of $100 and write an essay of 350 words or less answering the question: “What are your keys to living a sustainable lifestyle and how would owning the SustainaFest Tiny House help you realize your dream of living that lifestyle?” Submissions must be entered by June 1, and a winner will be announced by June 15.

There is one catch to the contest: The winner must find a location for the house and arrange for it to be delivered there.

All proceeds from the contest will support the efforts of SustainaFest to build more tiny houses with students in 2015.

For more information and to enter, go to https://www.sustainafest.org/tinyhousecontest.

Michele Lerner is a freelance writer. To pass on a tip or news item, contact us at realestate@washpost.com and put “Town Square” in the subject line.

For more Real Estate news, follow @PostRealEstate and visit our Facebook page.