San Francisco isn't known for predictable weather. Unfortunately, that means the prospect of building a proper year-round, Bavarian-style biergarten isn't necessarily a solid business idea.

Black Hammer Brewing, however, may just have it figured out: They're bringing the beer garden inside.

The new taproom is called Willkommen (German for "welcome") and when it opens to the public at 5 p.m. on May 17, it will feature an array of Black Hammer's beers. In addition to the German-style lagers and pilsners — many of which are gluten-removed — bartenders will also pour a few of the brewery's mainstays, like the Sparkle Pony Belgian blonde, and potentially a few guest beers, too.

RELATED: Black Hammer Brewing to open 'indoor beer garden' in Castro

"It was an inspiration from [owner Jim Furman]'s trip to Germany," says Cody Laxo, Black Hammer's product manager. "He really wanted to recreate that feeling like you're walking into Oktoberfest or enjoying some of the outdoor environments where people are drinking and it's lively and you're seeing large groups of people celebrating."

To get that real Gemütlichkeit vibe, Furman and Laxo installed two 14-foot maple trees as well as a living wall (to be maintained by a professional horticulturist).

"Its really hard to find places in San Francisco where you can take big groups and it's not a planning nightmare," Laxo says. "This was a really easy way to create that environment for people."

Food will be served as well, thanks to a partnership with local sausage-makers Rosamunde. In fact, the selection at Willkommen will be Rosamunde's most extensive of all their locations.

"We have Beyond Sausage so we have everything for the vegetarians," says Laxo. "We also have gluten-free buns and we can make almost everything gluten-free or vegan."

RELATED: Introducing Toke Back Mountain, Black Hammer Brewing's CBD-infused IPA

The biergarten marks a creative new venture for a brewery that thrives on outside-the-box projects. Last year, Black Hammer made headlines for its Toke Back Mountain, a CBD-infused IPA the brewery released at 4:20 p.m. on April 20. The beer was ultimately not around too long; it didn't include any THC, but the federal Alcohol and Tobacco Tax and Trade Bureau nevertheless ordered them to halt production.

Then in October, Black Hammer embarked on another effort: Hammertime, a semi-permanent pop-up beer bar on Polk Street. That bar will close on June 17, on the heels of Willkommen's opening.

Willkommen opens at 2198 Market St. in San Francisco on Friday, May 17. The bar is currently in a soft open phase in the early evenings. Beginning Friday its hours will be as follows: 11:30 a.m. to 11 p.m. Sunday through Thursday, and 11:30 a.m. to 12 p.m. Friday and Saturday.

Alyssa Pereira is an SFGATE staff writer. Email her at [email protected] or find her on Twitter at @alyspereira.

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