How the 'No New Things' sustainability challenge helps your wallet, the planet

Americans seem to be obsessed with things.

"The average American household has 300,000 things," according to sustainability expert Ashlee Piper. "We have more storage units than subways, McDonald's and Starbucks combined."

To save time, money and help the planet, Piper took on a "No New Things" challenge.

"When I was needing clothing, things for my home supplies, makeup -- things like that -- I was using what I had first," said Piper.

If Piper did need something, she said she could shop -- as long as it was secondhand. She said she turned to platforms that sell or trade used goods like Facebook Marketplace, eBay and Freecycle.

Challenge participants begin by writing down all the things each individual or household will need. If it's an item that's traditionally purchased new, then write that down and make a note next to it detailing how it could possibly be acquired in a different way.

Piper said she saved more than $16,000 in doing the challenge for a whole year.

"Every way that we purchase things, especially nowadays, is geared towards that immediacy," said Piper.