The former Bank of America building at 60 Throckmorton Ave.

The former Bank of America building at 60 Throckmorton Avenue.

In the two years since Jones Lang LaSalle Brokerage put the historic Bank of America building at 60 Throckmorton Ave. on the market, part of a raft of financial institutions divulging themselves of large real estate properties that no longer fit the legacy model of how consumers engage with banks, plenty of movers and shakers in Mill Valley and beyond kicked the tires on the nearly 4,900-square-foot building.

For a long list of reasons – the historic nature of the 112-year-old structure, inability to revamp the frontage to allow for beautiful storefront windows, the prohibitively high costs of downtown Mill Valley commercial spaces, the complexity of matching a viable business model to an extraordinary amount of square footage for a retail shop or restaurant and the massive impact digital platforms have had on traditional brick and mortar businesses, there were few serious prospects, by most accounts.

“If you are trying to check all those boxes, this is the opposite of that,” said Marine Layer founder and CEO Mike Natenshon, part of the team leasing the building, along with Marine Layer COO Adam Lynch and several others. All of the project partners live in Mill Valley.

It quickly became clear to the group that they weren’t going to successfully transform such a particular, peculiar space that will remain a long-term home for a Bank of America ATM into a retail space. “We spent a lot of time trying to see if we could make a retail concept work within this building before determining it was unviable, so we pivoted to this unique concept,” Natenshon said.

That concept is the Treehouse, an adaptive reuse of the building that seeks to transform it into a membership-based club that functions in similar ways to a gym membership or a co-working space but is built to celebrate and foster arts and culture in Mill Valley and beyond. The space would center around a reimagined social and cultural gathering space featuring a food and beverage menu that focuses more on “elevated bar food with a small, limited menu rather than a fine dining experience, with a hotel lobby type of vibe,” according to Natenshon. 

The Treehouse was the subject of a study session before the Mill Valley Planning Commission this week. A study session allows an applicant to receive a broad range of feedback from the commission and the public but without a decisive vote at the conclusion, thus allowing the applicants to respond and return to the commission for a formal hearing down the road.

The Treehouse would likely operate from 10am-10pm – within the range of similar requirements for the likes of Playa, Bungalow 44 and others – but wouldn’t rely on being a late night establishment. “Events will be a big part of what this project can bring and add to the fabric of the community,” Natenshon said. He also noted how the Treehouse could fit into the larger fabric of Mill Valley, which has definitely become “a destination for people who want to get out of the city, go for a hike, grab a bite and engage with arts and culture.”

The project requires a conditional use permit, meets building height requirements and design guidelines but does not meet current parking requirements.

The three elements that drew the most response from both residents and commissioners were the business model, the proposed roof deck and, of course, parking.

Business Model

“We believe the membership is the way to brung this project to life,” Natenshon said, noting that the cost associated with the renovation of the building will require early funding to get the project off the ground. We want this business to be successful and have it here for a long time. Paid memberships are part of that. There will also be consideration for having a diversity of lifestyles and incomes, and there will be room for in-kind memberships for artists and residents of places like the Headlands Center for the Arts and similar organizations.”

“We’re endeavoring to bring something that would enrich the dialogue of the group, wanting to contribute and enrich the community,” he added. “We want a diversity of applicants and a diversity of rich dialogues. The point of the application process is to foster that participation and enrich our community which is the goal of what we are trying to do with this organization.” The Treehouse would feature structured programming and interactive events, some open to the public, he said.

“I don’t want to feign exact precision at this moment,” Natenshon said. “The plan has been thoughtful and considerate of a lot of the concerns we are fielding from the comments we’ve heard so far.  There’d be a very liberal guest policy.”

The Roof Deck

With a full capacity of less than 50 people, the roof deck would not have any food or beverage service for safety purposes, nor any amplified music.

“We see it as a place to be in the quiet and enforcing some good neighborhood policies,” Lynch said, noting that, although they are in the early stages, the deck would likely feature plenty of low couches and coffee tables and chairs.

“We’re trying to balance different considerations with the roof deck, Natenshon said. “It is is important that it be simple but special. It’s a really beautiful perch to see the town and the surrounding areas. It’s a great spot to hang out with a few people. It won’t be a late evening thing, but on a beautiful summer night, it’ll be great to enjoy the view and some time there.”


Mill Valley Market co-owner Doug Canepa expressed concerns about the membership component and the project’s impact on parking. “The pertinent question is who are they going to deny access to? You’re kind of squeezing in a project that already has intensive use as it is.”

In an interesting twist, for larger events, the Treehouse would provide a full service shuttle for members, a nod to the fact that the parking associated with the building could rise as high as 66 spaces on weekend, and spaces within the corridor around the Sweetwater, City Hall and the Treehouse could be limited at times. The city’s parking analysis did not account for people walking or biking to the business. The space would have dedicated bike parking.

Commission Vice Chair Eric Macris asked the applicant to consider how the Treehouse would engage and interact with other changes  at the intersection of Throckmorton and Corte Madera avenues, namely to expected arrival of the No. 9 locomotive outside Mill Valley City Hall in the years to come. This could be part of a fantastic, vibrant block that right now feels like you are now behind the real downtown.”

“The whole thing’s a little complicated but we’re working on it, Natenshon said. “If we are invited back, after gathering all of the feedback, we could present how we are viewing the membership model and this number of free memberships and guest access to help facilitate access and vibrancy.”

“I’m actually really excited that someone has taken this building and turning it into something,” said Maria Hoppe, executive director of the Sweetwater Music Hall. “It has been vacant and not looked after at all. I’m very happy about that. On behalf of the Sweetwater board, we are all for developing vitality in the downtown area. We are on this block that no one every turns up. This will bring more awareness of everything that’s up here. But when you do the noise testing, make sure it’s at a time when there’s a wedding at the Outdoor Art Club and a concert at the Sweetwater.”

Commissioners also emphasized the need for the kind of successful good neighbor policies that the Sweetwater Music Hall has successfully leveraged in recent years.

Planning Commission Reaction

“In most scenarios to make this work, this building would be torn down,” Planning Commissioner Kevin Skiles said. “It’s fantastic that you’ve come up with a way to save it.”

The commission considered the issue of parking, specifically that the Bank of America building would be associated with 60 parking spaces downtown. Skiles noted that during the years of the renovation and reiteration of the Mill Valley Lumber Yard, there were significant community concerns of ‘parkageddon,’ a traffic nightmare that would destroy the character forever. “There are no parking issues,” he said. “In recent years, people tend to think of alternative ways to get downtown. It tends to work and function and I have a lot of faith that people will choose alternative methods. When we’re making 100-year decisions about land use, the idea that anyone is going to be driving to Mill Valley in 30 years is laughable. It is a problem that is going to sort itself out.”

“With climate change, we have to start thinking differently and finding ways to leave the car at home,” Commissioner Greg Hildebrand said. “We can’t re-envision Mill Valley around the automobile. I know that is harder for the people who are living right downtown, but you have to walk or bike.”

“The fact that somebody is trying to come up with a business model to renovate this building and keep it intact – we have to give them credit for that,” he said. “If we don’t get something in that corner, then the space is dead – it will just sit their vacant.”

“I encourage the applicant to hear the objections and concerns about membership,” Commissioner Ernest Cirangle said. “As you develop the proposal, it would be good for you to come back to us with a proposal on how this could be more of a hybrid model that includes access for non-members in some capacity. You’d be best to figure that out, and it would be important for us to hear that.”

The Planning Commission will host a formal hearing on the proposal in the coming months.

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