Ty Pennington, the OG of household renovation demonstrates, talks about internet hosting HGTV’s Rock the Block. (Photograph: HGTV) Ty Pennington by no means could have predicted his Tv set occupation longevity when he 1st stepped on the set of Trading Spaces, slinging his instrument belt, again in 2000. About two decades later, the carpenter-craftsman-designer is juggling several displays on HGTV, like Rock the Block, for which he serves as host with his signature large-strength design. The show’s fourth season premieres on Monday. “It’s funny — when I meet new folks on HGTV, they’re like, ‘Oh my God, you happen to be the OG,'” he tells Yahoo Entertainment. “And I’m like:…