Drew and Jonathan co-hosted Tuesday's episode of ET, where they dished on their new HGTV show, Celebrity IOU, and working alongside the Oscar winner, as well as Melissa McCarthy and more stars, to help them give back.
"He's a Property Brother from another mother," said Jonathan, about Pitt, with Drew adding, "We all have the same abs."
"A lot of people don't know he is so into architecture," Jonathan said. "He's brilliant when it comes to the home. So the fact that he was part of our premiere episode of Celebrity IOU is amazing."
"I will admit when we were doing demolition, he beat me through the walls. Like, he smashed through that thing like no one's business," he continued. "Really, it was so cool to see someone that's such a huge celebrity just want to get in and put his own hands in on the work because he wanted to do this for someone he loves."
"Celebrity IOU, basically, we partner with huge celebrities," Jonathan explained. "And they want to give back to somebody who's really important in their life. They partner with us to make that happen."
The celebs involved in the series, aside from Pitt, include Melissa McCarthy, Viola Davis, Rebel Wilson, Michael Buble and Jeremy Renner.
The first episode shows Pitt helping out his makeup artist, Jean Black. "Well, Jean's been with him for over 30 years. This is somebody who’s been with him through thick and thin," Jonathan said, with Drew adding, "When you see them together, it's almost like two kids, really funny together."
There's also McCarthy, who's pretty handy with a power tool. "Melissa is so funny during demolition as well," Jonathan elaborated. "There is nothing she would back away from."
Meanwhile, last month, fans got to see the Property Brothers, as well as sisters Zooey and Emily Deschanel on Carpool Karaoke: The Series. This is where Jonathan and the New Girl star's romance began.
"I was playing it super cool," Jonathan shared. "Initially, I was playing it cool and it was fine and I looked at the episode when we screened it and it looked like Zooey was flirting with me on the episode. The producer's though, were like, 'No, no, no. You were so bad, Jonathan. You were flirting so bad we had to edit it down.'"
As for meeting his parents for the first time, "She can literally never do wrong in my dad's eyes," Jonathan confessed. "The first time we FaceTimed with Mom and Dad, she sang my dad's favorite song. She sang 'Danny Boy' and my dad literally teared up, and then after, my mom texts and says, 'She's perfect.'"
Celebrity IOU premieres Monday, April 13, at 9 p.m. ET/PT on HGTV.