Kutcher surprises mom with renovation

"There are a lot of reasons to go home and do something special like this," says Ashton Kutcher.

"But really, at the end of the day, it's my way of saying thank you to my mom. My mom's been the greatest influence in my life. And anything I can do to say thank you is the right thing to do."

That's Ashton Kutcher talking about mom Diane. The star teamed with Houzz.com to renovate the basement of his childhood home in Homestead, Iowa, the "place that I call home."

It's documented in four videos on the Houzz site.

Kutcher says he and his stepfather, Mark, built the house years ago, when Kutcher, 37, was 13. It's time for an update. He and a crew knocked down walls, lifted the ceiling and added lots of windows for natural light.

"If my mom doesn't like, somebody's in big trouble," he says, pointing to himself.

The end result, in the fourth video of the series, is everything you want it to be. Spoiler alert: The basement is beautiful, and Diane, who is just back from visiting Kutcher's wife, Mila, and their new baby, is surprised to tears.