Ty Pennington — the hot handyman from TLC's Trading Spaces — calls himself "a blend of Martha Stewart and MacGyver." But it's not easy. Sometimes the show's tight time constraints, limited funds and diva-ish designers make Ty wanna drive a nail through his skull!

"We all have our little clash of personalities," the 37-year-old admits to TV Guide Online. "It's like Real World meets This Old House. It's kind of fun because you never know what's going to happen."

Who's been the toughest to work with? "I'm not going to mention any names," he teases. "But there are definitely some [projects] I have been involved in that I didn't even know if I wanted my name associated with. There have been several projects where I'm like, 'This is wrong. Not only does it look wrong, it doesn't even work, and there are safety issues.' We put two automobiles in a kid's room for Chrissake!"

Pennington will share his how-to dos and don'ts in an upcoming book of home improvement advice. In addition to writing that and starring on Spaces — which airs Saturdays at 9 pm/ET — he runs his own company, Furniture Unlimited, and serves as a spokesperson for Claritin allergy medicine.