Beth and Craig Wathen have a vision for their forthcoming City Beer space on Mission Street: it’ll be a cavernous beer library where customers are set adrift in a sea of labels and high-quality restaurant food.

Barring any permitting or construction delays, City Beer’s new digs will open to the public sometime in August. The Wathens told Inside Scoop they plan to vacate their current space by July 31, and around the same time they’ll be handed the keys to 1148 Mission St., the one-time home to Charles Phan’s short-lived British restaurant Coachman.

Overall it’s a grand endeavor for the City Beer team when considering how over the last decade they’ve quietly catered to a cult following in a diminutive, subterranean hangout on Folsom Street. Suffice to say popularity over the last few years in the beer world brought them new customers, which in turn caused a bit of an overflow in business.

“We’re lucky to add more square feet because now we can actually create comfort zones throughout the space,” Craig said. “It’ll be interesting to see people in it when we’re finished.”

Notably, City Beer’s Folsom Street home was about 1,800 square feet while their new space is about 4,500 square feet. In an effort to utilize every inch of the extra room, as well as hook customers into staying, drinking and eating, Beth Wathen said the new City Beer will have its bottle shop toward the back of the building, an area that will also have a rotating cast of art installations.

“The back bar will be a littler more comfortable and darker and more intuitive to a bar experience,” Craig added, which means City Beer will also have custom-made benches for folks to lounge around on.

For the City Beer crew, the only detail of the new space with the most work left to be done before it becomes a solid idea is the kitchen. For now, Beth said they’re just excited about having access to high-end culinary equipment.

“The space already had a sophisticated, gorgeous kitchen so we left it intact,” she said. “When it comes to the menu, we just have to find a food concept that makes sense for the model.”

Harkening back to the beer library aesthetic, the City Beer team said they’ve always viewed the act of purchasing beer as a uniquely social interaction. It’s a mindset that will be weaved into the design and layout of their new location.

“We’re still in the middle of construction but we can see it coming together,” said Craig.

City Beer moving to 1148 Mission St.; Closing date for 1168 Folsom July 31.

Justin Phillips is a San Francisco Chronicle staff writer. Email: jphillips@sfchronicle.com Twitter: @JustMrPhillips