Case Study: Seattle’s Machine House Leans Into Cask Ale

As a small brewery devoted to cask-conditioned ale, Seattle’s Machine House is a rare bird in the United States—and it’s one that recently marked a decade of brewing, guided by the pragmatism of founder Bill Arnott and his “simple, primitive” approach to making their distinctive yet highly accessible beers

Joe Stange Dec 21, 2023 - 22 min read

Case Study: Seattle’s Machine House Leans Into Cask Ale Primary Image

Brewer Justin Moran and Bill Arnott, founder and head brewer. Photos: Bettina Hansen/Machine House

At times, Bill Arnott has found himself soul-searching, trying to work out whether it’s worth continuing the unique business he started a decade ago in Seattle’s Georgetown neighborhood.

“Just in a logical way,” he says. “Does it make sense to keep this going?”

It’s a question he asked himself during a pandemic that was tough on draft beer but positively brutal on Machine House’s cask-conditioned niche. And it’s a question he recently had to ask again when their landlords announced a significant rent hike—compelling either the search for a new home or an end to the adventure.

Arnott says he approaches the question logically, “but you can never really take the emotion out of it. ‘Do I have it in me to keep doing this?’”


So far—to the delight of local beer enthusiasts, British expats, fellow brewers, new cask converts, and new neighbors—Arnott’s answer has been yes.

As independent brewing continues to evolve, it’s ultimately up to each brewer and business owner to decide what success means to them—that’s what it means to be independent. For Arnott, that equation includes two young children, a spouse who has her own demanding job, and a type of beer that’s beloved among some yet will never win mainstream popularity in North America.

“I have a one-year-old and a three-year-old,” Arnott says. “My kids take up probably 80 percent of my energy, and the brewery gets the rest. And I’m not going to compromise too much on that.”

Arnott and team found their new home in Seattle’s Hillman City neighborhood. When they announced the move, a lot of their customers—understanding, perhaps, that its future was no sure thing— jumped at the chance to support Machine House while they could.

“And I think the amount of general sentiment, and the support we got from people—that definitely helped to boost the sense of, ‘Okay, we can keep this going, and this can be successful if we manage this transition. It doesn’t have to end here.’”


Right: The original brewery once housed the Rainier brewery, before Prohibition. Left: The new neighborhood-focused Machine House brewery.

How It Begins

The roots of Machine House lie not in Seattle but in the pubs of Norfolk, England, where Arnott was born and raised.

In and around Norwich, Arnott got early exposure to the local drinking culture; it’s legal in Britain for 16-year-olds to drink in pubs when accompanied by an adult. While he wasn’t especially picky as a teenager, he got to know beers such as Adnams Southwold Bitter, at 3.7 percent ABV, and Woodforde’s Wherry, at 3.8 percent. “How I grew up, you got lager or you got bitter, basically,” he says.

Later, while studying history at the University of East Anglia, he did a study abroad year at the University of Oregon in Eugene. “I got exposed a little bit to U.S. craft beer at that time,” he says, “even though I was technically too young to drink.” He was 20, “which was the worst age because I’d been drinking in England for five years, and I couldn’t buy beer here. But, you know, you just find a way.”

With a budding interest in organic farming and a newfound affinity for the Pacific Northwest, Arnott later apprenticed on a farm on Vancouver Island, British Columbia, where the next piece fell into place. “This other guy who was just passing through now and again was into homebrewing,” Arnott says. “And I was like, ‘Well, I would love to learn how to brew, that sounds great.’” He soon made an amber ale with nettles and spruce tips grown on the farm. “That was my first taste.”

He returned to England in 2008 and started looking for a job there. Soon he learned about an opening at a local brewery called Tipple’s. Owner Jason Tipple hired and trained him. “I just kind of learned on the job,” Arnott says. “Just a small, local brewery making cask ale—open-fermentation cask ale—just like a lot of those small breweries at that time.”


He brewed at Tipple’s for more than a year before moving to Seattle to be with his girlfriend. “I really liked brewing, but I wasn’t really sure it was going to be a career path for me,” Arnott says. The couple moved in together and got married, splitting up about a year later. “Long time ago now,” he says. “It was a good-faith marriage. … I had no reason to want to move to the States other than to pursue that relationship. But once I’d moved here, I was like, ‘Well, I kind of want to stay.’”

Stay or go, Arnott needed a livelihood—and what he knew how to do was brew. However, he was in a city already awash in craft beer. He asked himself, “‘How are we going to stand out, or make this worthwhile?’ I really did not at all want to just be another brewery that’s just adding to this pile of breweries making the same kind of stuff. What’s the point of that, really?”

His cask-ale experience was unusual, locally, but he knew it would be a hard sell. “Probably not the best business sense,” he says. “But you’ve got something totally unique, and I knew it could be really good.”

He also knew it would be distinct. “Honestly, if I’d decided to open a brewery in England in 2013, I would probably be doing more modern American-style stuff because that was what would be missing there at the time. I’m not going to make a better bitter in Norwich than all the breweries there that are already doing it. Is it going to be better than Adnams or Landlord or Harvey’s or whatever? Maybe. But probably not. Whereas here, I was like, ‘Am I going to make IPAs and stuff better than Elysian and Georgetown and Fremont? Probably not.’ I was slightly pragmatic in that way, but it was easy to convince myself that cask ale was going to be the way for us.”

With cofounder Alex Brenner, Arnott opened Machine House in 2013 in a historic, cathedral-like industrial building—until Prohibition, the home of Rainier Brewery. Rainier is long gone, but Machine House has lasted more than a decade, no doubt outliving many people’s expectations.


A “Simple, Primitive Brewing Process”

There have been ups and downs. In 2018, they opened a satellite taproom in Seattle’s Central District. The next year, Arnott and Brenner parted ways; Arnott became lead owner—there are a few others in the LLC—while Brenner turned the Central District taproom into a cask-centric pub named the Capercaillie. It had a devoted following, but the pandemic’s reverberations were unkind; the pub closed in 2022.

Machine House survives, and even after a decade it doesn’t stray far from its session-strength roots. Its flagships from the outset have been Best Bitter (4.2 percent ABV), Golden Ale (4.5 percent), and the local cult favorite Dark Mild (3.7 percent). The bitter and mild are the top sellers. Arnott is openly proud of the mild, rich in color and malt flavor yet light in strength. He describes it as “a beer that I really wanted to make just because I knew it could be really good and just completely unlike anything else that was around at the time.”

Many of the rotating ales on the taproom’s eight beer engines are bitters or pale ales that rarely stray above 5 percent. These often include an ordinary bitter called Cambridge, preferred by many of the regulars, at 3.8 percent ABV.

From the start, Arnott has leaned into what he knows.

“What I come back to is the brewery I worked at in England and the ones that I saw,” he says. “It was just a really, really simple, primitive brewing process that resulted in insanely good beers. There [are] obviously different brewing techniques and principles, practices in different places. But as far as those classic English ales, it does seem like keeping it super-simple just works. That’s why we stick to doing the open fermentation and cask conditioning. ... Those things—as much as they’re a pain in the ass in certain ways and create some unpredictability—what they add [is great]. The rest of the process is so simple.”


It starts with a single-infusion mash, typically at 152°F (67°C). And while Arnott likes British malts, he doesn’t view them as strictly necessary, nor does he use them exclusively. “I like to use Maris Otter or Golden Promise or some high-quality British malt, but these beers work with American malt too, in my opinion,” he says. “And if you look at British brewing history, they used ... the cheapest, most accessible malts they could get, and hops as well.”

Likewise, Arnott and brewer Justin Moran enjoy mixing U.S. hops with English, German, or Slovenian varieties at times—one recent bitter featured East Kent Goldings as well as Mandarina Bavaria, while another got English-grown Progress with a bit of Strata and HBC 586, “for a kind of fresh fruitiness,” Arnott says. “So, we’ll play around.”

The boil is classic, typically 60 minutes with a few hop additions. Fermentation is where things arguably get weird, as they rack the wort into the single-walled, wide-open vats that serve as fermentors. These vats are only a bit larger than the brewhouse’s seven-barrel capacity; Arnott describes them as “undersized.” They’re in a dedicated room, away from the dust and other things that float through a brewery’s air.

“We open-ferment—probably on the warm side in general, without a great degree of control,” he says. “It’s not like we don’t pay any attention to the fermentation temperature, but we let it rip pretty good.”

That rigorous, barely controlled fermentation is the heart of the Machine House process and the key to its beers’ character. “We haven’t used closed fermentation, so it’s just different,” Arnott says. “I feel like other brewers see what we do and are a little surprised, but maybe that’s an understatement.”


For the most part, they use two yeast strains: Imperial’s A09 Pub and A05 Voyager—unofficially associated with England’s Fuller’s and Timothy Taylor breweries, respectively. Arnott prefers Pub for the mild and other malt-forward styles, though he says it doesn’t perform as well in the warmer summer months. Voyager, meanwhile, seems to do well year-round and stay healthier through more generations of re-pitching.

Primary fermentation takes four to six days—five is typical. “And then we’ll rack to a brite tank and usually package the next day or the day after.”

The next step is conditioning—whether for cask, bottle, or even keg. Machine House primes with a bit of dextrose, even if more traditional British ale brewers rack to casks directly from primary, when the fermentation isn’t quite complete. “We’ve tried it both ways, and [priming] just gives us a little bit more control,” he says, “and the beers just seem to come out a bit crisper and cleaner and clearer that way.”

They do brew IPAs—this is the Pacific Northwest, after all—but Arnott prefers to put those on keg alongside the guest taps. “I could buy an IPA from another brewery,” he says, “but I’m like, ‘Well, we can make an IPA. … We have made cask IPA, but it’s not my favorite way of doing it. Maybe a real traditional IPA on cask would be cool, but that’s not what most people want. And any kind of modern IPA, to me, just tastes better on draft.”

Being in Washington, they also get fresh hops at harvest time, adding them to IPAs as well as cask bitters. “We’ve always done it because it’s just fun, and it’s a unique opportunity for us,” Arnott says. “And even though everybody around here makes fresh-hopped beers, they still sell well. And ours are unique in their own way because of our process.”


Serving and Selling Cask

In the Machine House taproom, they’ve never used cask breathers—devices that release CO2 to keep out oxygen—to extend the life of the beers. While Britain’s Campaign for Real Ale (CAMRA) recommends that cask ale be used up within three days, Arnott says they can typically keep theirs on for twice that long—if there’s still any left by then—before the flavor deteriorates. Their carbonation also starts a tad higher than the CAMRA standard, while in summer their temp is a tad cooler—about 50°F (10°C) instead of 52–55°F (11–13°C).

“I guess to an extent, we feel a little bit free from those rules,” Arnott says. “We can kind of make our own version.” Part of that license comes from working to overcome the stereotype of British cask ale as warm and flat—Machine House beers are served cool, and they have some zip. “Nobody should have to drink warm and flat beer,” he says. “You don’t have to do it that way—it’s not good. … And, equally, you don’t have to take a firkin and put novelty ingredients in there just because that’s what people have been doing in the U.S. for years. You can just brew it in a way that’s going to taste good.”

Machine House typically sells 20 to 25 percent of its volume over the bar in its own taproom. “We’d like it to be more because we know we serve it in the best way,” he says. They also bottle, “going for the best version of an English bottle-conditioned ale,” and those go into distribution; Arnott estimates that about 30 percent of their beer over the past five years has been bottled.

Another 10 percent or so, lately, has been kegs—conditioned like the casks, but with higher carbonation. That was partly a reaction to the pandemic. “As much as the draft market hasn’t recovered entirely, it’s recovered better than the cask market,” Arnott says. “It has in the last couple of years helped to keep our wholesale sales up because we could see the writing on the wall with the cask sales, for the time being.”

At the new location, Arnott says they plan to move away from conditioning the kegs, which inevitably have sediment that leads to cloudy pints. Instead, they might use spunding to naturally carbonate—or even force-carbonate—but only for kegs. “We’re a weird brewery that’s never done that before,” he says. “We never had glycol at our old place—which is not something I’m particularly proud of; it just worked for our system at the time. There were definitely times when it would have been nice to have some tank temperature control, but I re-created the system I used in England, which is very basic, very simple—open fermentors in a semi-controlled room, and then brite tanks in a walk-in. So, we just had very limited capacity to cold-crash, or to force-carbonate, or anything like that.”


The rest of the business is selling cask ale wholesale to those rare yet wonderful bars that want to pour it. There are several accounts—fluctuating more than usual over the past few years—in Washington and Oregon that get Machine House casks and serve them on beer engines. These include Seattle bars such as the Brouwer’s Cafe, The Cozy Nut Tavern, and Chuck’s Hop Shop, as well as cask-friendly Portland spots such as the Horse Brass Pub.

It’s a business that Arnott has worked hard to build, slowly and steadily. Convincing a bar to install a beer engine and take on cask is an order of magnitude away from convincing them to put your kegs on draft now and then. Cask ale requires specialized equipment and know-how—and today, many bars are just trying to stay afloat.

“We built that up pretty well, up until the pandemic—more and more people installing beer engines to pour our beer or whoever else’s,” Arnott says. “And then everybody just stopped because business is, at best, very slow. And then you’ve got this product that is kind of finicky, and you have to go through it quickly—an easy thing just to cut out straightaway. That business that we developed got pretty well decimated, and we’re having to figure out how to bring it back.”

A Brewer’s Brewery

The Machine House team is small—Arnott, Moran, and three others, including a part-time bartender. Last year they brewed a bit less than 500 barrels. “I expect that to increase here in the new spot,” he says, “but everything has been so unpredictable the past few years.”

The new location isn’t totally random—Arnott lives about five blocks away. Hillman City is a more residential area than the old, industrial Georgetown digs. “I’m really hoping we end up with a lot of that foot traffic here,” he says. He loved the old location and its history, “but being in that industrial neighborhood, it was more of a destination—people had to come and find us.”


The regulars who found them before will find them again. But now, Arnott says, “we also have a neighborhood of people, [and] we can just service them directly—which is so much more like the English pub way. People can walk to your spot and enjoy a beer and a chat with neighbors. I’m really hoping that develops here.”

Given their niche, the brewery attracts more than its share of British expats, as well as locals who simply enjoy cask ale—and not just well-traveled geeks. “It’s a lot of brewers, really,” Arnott says. “Sometimes I’ll look at the people in our taproom on a weekday afternoon, and it’s almost all people [who] work at other breweries.”

Others are simply converts. “We’re not the most conventional brewery,” Arnott says, “but we try to make it really accessible—try to have a really friendly experience for people, to make it comfortable. Because it shouldn’t be scary. We’re not trying to make something weird; we’re trying to make something that’s enjoyable for a lot of people. … Despite the fact that it’s not as cold, despite the fact that it has the word ‘bitter’ in the name—all these things that basically make it harder to sell—a lot of people just find it to be really good.”

While the new location brings fresh optimism, Arnott shares a rational perspective that’s been seasoned by the past few years.

“I hope that we continue here for a long time,” he says. “But … I’ve seen so many friends and people—at breweries, bars, restaurants—who have closed down. I don’t see it as a bad thing for them. Like, it may be a good thing for them. And, at some point, that may be a good thing for me. But I’m not really thinking about that right now. … You want to look forward, you want to be setting goals and thinking big, but also … there’s no shame in shutting down. It may be the right thing for you.

“But one thing I would say is: I feel like it would be a big loss, a brewery like us closing.”

Joe Stange is Managing Editor of Craft Beer & Brewing Magazine® and the Brewing Industry Guide®. Have story tips or suggestions? Contact him at [email protected].