Rainey Street is about to get a whole lot more barbecued meats and draft brews.

An ambitious, multimillion dollar expansion at one of the most popular bars along the downtown street, Banger's Sausage House & Beer Garden, will be officially unveiled this weekend in the form of a new two-story building on the north side of the property. In total, it adds an extra 15,000 sq. ft. of dining, lounge, event and performance space to the bar's sprawling complex.

For owner Ben Siegel, the project — which gives Banger's what might well be the largest draft beer system in Texas — was necessary for the growth of the bar, which was getting to be too small for the number of people who visit.

"One of the things that drove us to add on next door was addressing our space issues in the kitchen and giving ourselves the facilities necessary to do a really excellent job," he said.

The new Banger's building, at 81 1/2 Rainey St., features a new smokehouse, a custom room dedicated to the fermentation of pickling and vegetables, and a full meat processing facility. Plus, because Banger's regularly hosts private events, there's a private events space in the basement that can hold 300 people. And with more than 5,000 sq. ft. of added outdoor drinking areas, the bar can hold roughly 1,800 people overall.

For all those people, of course, Banger's needs to have a lot of beer on hand. The original bungalow has 106 taps, and a new outdoor beer bar has been outfitted with 101 — bringing the total number to a whopping 207.

When the expansion opens Friday evening, everything but the smokehouse will be up and running. That's expected to open later this month, according to a press release, and focuses on something that Banger's has loved from the beginning: whole hog roasting. Banger's has been cooking whole pigs regularly since opening in the bustling entertainment district six years ago and will begin doing so again out of a 10-foot fireplace. And, of all the aspects of the expansion, it's probably Siegel's favorite.

"It's a standalone barbecue concept," he said. "When it opens, it'll be the first ever, in the history of Texas, whole-hog barbecue restaurant. To qualify that, lots of people have cooked pigs before, we cook pig once a month, but no one's had it as a standing menu item that we've been able to find. Four days a week, you'll be able to get whole hop in chopped and pulled pork format."

With the expansion, Banger's can take its focus on specialty sausages and beers to the next level. Celebrate its grand opening starting at 5 p.m. tomorrow. The new building is open only on weekends, from 5 p.m. to close on Friday and Saturday and 10 a.m. to 4 p.m. Sunday, until the smokehouse is ready. At that point, the hours will be expanded.

For more information, visit bangersaustin.com.