Before you enter “Entourage” star Adrian Grenier’s Clinton Hill Victorian townhouse, toss your junk food to the curb.

“There’s no soda and no potato chips allowed in the house,” says Grenier, who has eschewed the Hollywood limelight for a Brooklyn Renaissance-man existence complete with farm-to-table fare, eco-friendly mandates (plastic bags be damned), Churchkey beer, headphones glued to his neck, and jam sessions at his in-house studio. His modest digs, where at least five key-bearers come and go as they please, have the eclectic, distressed charm of Paradiso Perduto, the crumbling mansion in the 1998 movie “Great Expectations”: A dolphin statue here, a Jesus painting there, a “dark” version of “Jingle Bells” being pounded out live in the distance.

It’s a far cry from the life of playboy actor Vincent Chase, the “Entourage” role that made Grenier famous and which he’ll be revisiting in the big-screen version of the hit HBO series set to start filming “soon,” according to the actor.

“The one similarity that we both have is big eyebrows and big hair,” says Grenier. “As much as all the guys wish they were Vince, so do I. It would be so great if everything just worked out and you could live that lifestyle with no consequences. But the reality is, that’s a fantasy character.”

Grenier’s reality is less models and bottles, more 36-year-old hipster entrepreneur with a backyard herb garden.

Right now, Grenier, is focused on his project du jour, Wreckroom, a recording studio located in the basement of his home, where friends and musicians can gather, free of charge, to make sweet, sweet music.

The NYC native launched the music initiative last January. Tracks are produced, then videotaped and posted online at wreckroom.tv. So far, 55 bands — including Grenier’s own, the Honey Brothers (he’s the drummer) and teen Brooklyn-based rock band the Skins (Grenier’s pet project) — have been “wrecked.”

“I don’t know any celebrities or any well-educated being who would open up their homes like this,” admits Damien Paris, Grenier’s childhood BFF and head Wreckroom producer. “But it’s part of the trust.”

“He’s just so generous that you can’t help but be happy to be here,” says Daisy Spencer, the 19-year-old guitarist of the Skins (the only group Grenier and Co. has signed on to manage — Wreckroom is not, Grenier stresses, in the band managing business).

“We’re fiercely independent and we support other independent artists who are struggling to survive in this economy,” says Grenier, who thinks the Skins have great talent and “really make us look good.” Plus, they “need our guidance on a business level.” If Grenier’s dizzying résumé is any indication, he has plenty of guidance to give.

The HBO hunk is the co-founder of SHFT, a digital platform dedicated to sustainability, which, last May, launched the Mobile Kitchen Classroom — a scheme to teach city kids how to cook healthily. He’s also a member of two bands: Honey Brothers and the duo Caldwell (Grenier is rumored to be dating bandmate Emily Caldwell). If that weren’t enough, last summer he co-founded Churchkey Can Co., a retro, flat-top steel-can beer company that he hopes to eventually distribute in New York. Plus, he still finds time to toil at his local food co-op and, yeah, occasionally act and produce.

“To be honest I feel like all of my projects fit together in a nice sort of complementary way,” says Grenier. “They’re all cut from the same sort of spirit and intention. It’s all about doing it yourself, participation, engagement in life and living a full exciting and creative life.”

But despite all the good that comes from Grenier’s enlightened existence, he admits that 2012 “has been a bit of a struggle.”

“I haven’t really pursued the obvious, easy revenue through acting. Instead I’ve indulged my entrepreneurial spirit … so 2013 is going to be a big year for these projects that I started,” he says, “and that’s what I’m excited about.”

Grenier’s low-key, almost zen-like approach to life might be surprising to his hordes of hormonal fans and the frenzy of celeb bloggers.

But to his real-life entourage, it’s a natural maturation.

“Adrian’s a superstar, but he’s kind of a p—y,” says Paris. “He’s not like Mr. Party guy. He’s a normal dude. He plays chess. He likes dinner parties,” Paris adds, pointing out Grenier’s much-mocked love of Phil Collins.

“I like to cook broiled steak,” says Grenier. “Organic grass-fed,” he adds.

“He pretty much wants to be the big fish, I guess,” Paris jokes when asked why Grenier doesn’t keep a posse of famous pals. “Or maybe the other celebrities are like, ‘We don’t like you.’ ”

That doesn’t mean that the actor, who is obsessed with growing his hair out, according to the Skins, doesn’t have his celebrity diva moments.

“He has two phones.” says Spencer. “He’s like, ‘If I don’t like someone, I’ll give them this number.’ I’m like, ‘That is unnecessary!’ ”

“But he’s married to his phones …it’s the celebrity in him.”

dschuster@nypost.com