Evanston RoundTable, Nov. 13, 2025

The two oldest businesses in Evanston — Cahill Plumbing, Heating and Air Conditioning, founded in 1890; and Lemoi Hardware, founded in 1895 — have been around for a combined 265 years, older than the republic!

And each has been run by the same family for more than a century, which is extremely rare.

Amazingly, Lemoi remains at the same site where it started over a century ago, at 1006 Davis St., although it has added considerably more adjacent storefront space since then.

The first thing owner Ralph Lemoi Dupuis mentions, when asked about the business, is how much he relies on his staff.

“I’m on the business, they’re in the business,” he says by way of sharing credit for the store’s long-running success with his 23 full- and part-time employees.

Pot-bellied stoves

Lemoi was founded by Dupuis’ great-grandfather, Peter Lemoi. The store’s origins date back to a partnership between Peter and a man named Peterson (first name lost to history), who established a sheet metal repair shop in 1894. Among other services, they fixed pot-bellied stoves around town, including at Northwestern University’s Willard Hall. (Dupuis noted that Northwestern is still a customer.)

The partners split up when Peter Lemoi opted to expand with more products, and took a 2,500-square-foot space at 1006 Davis St. in 1895. Over the years Lemoi expanded to 1008, then 1010 and finally 1004 Davis St. The combined 10,000 square feet of space is four times the size of the original store.

Today Lemoi stocks more than 56,000 SKUs, or stock keeping units. But many of those products are carried in multiples: Think of a box of 2-inch nails as one SKU, but containing 200 or more nails. In other words, the number of individual items in the store might be close to half a million, Dupuis estimates.

Just for fun he checked his records for a single day last July. The store sold 5,700 products.

That’s a lot of nuts and bolts.

Lemoi is a longtime Ace hardware franchisee, and Dupuis is highly complimentary of their relationship, citing numerous logistical and financial services that Ace provides. Ace is equally enthusiastic. “Lemoi Hardware holds a very special place in the Ace family,” said Ace chief executive John Venhuizen. “As one of our longest-standing and most respected retailers, they’ve built deep trust with generations of Evanston neighbors. Their commitment to helpful service and community embodies what Ace Hardware is all about.”

Happy customers

Local customers also appreciate the store. Wrote Nina on the rating site Yelp, “Lemoi Ace Hardware has been in the area since 1895. The ability to stay in business for that long says a lot about the quality and service they put out. My recent experiences are testament to that and I hope they stay in business for generations to come.”

Cahill gets some love on Yelp, too. “The work results have been nothing but A+,” wrote Margaret. “I am very satisfied by the competence and honesty of the people who work there,” said John.

The business, located at 1515 Church St., has 21 full-time and two part-time employees. They do plumbing, heating and air-conditioning work as well as kitchen and bathroom remodeling in Evanston and throughout the North Shore.

John J. Cahill came from Dublin to Chicago in the mid-1880s and moved his plumbing business in 1890 to Evanston. His grandson, co-owner John J. Cahill II, 83, still comes to the store almost every day.

“I love the people I work with, and I love our customers,” he told me. “Maybe that’s why I’m still alive.”

Starting young

Cahill grew up in Evanston and worked at the family business from the time he was 10 or 11. “I learned something every day.”

He was finishing his freshman year in college in 1962 when his father, John W. Cahill, became ill and asked him to return home. “Working for your dad means working long hours, pretty much sunup to sundown. That’s how you learn the business,” he recalled. He bought the business from his dad in 1970. “I worked 80-hour weeks the first 20 or 25 years I was here.”

He pointed out that most of the firm’s work starts when people have a problem, “when something’s broken, something’s flooded. So that’s our business: We’re helping people in a pinch.”

One such pinch was a severe ice storm in the 1980s. He recalled that local TV crews joined Cahill plumbers to film them thawing out frozen pipes.

There are a lot of plumbing and HVAC businesses in the northern suburbs, including Cahill Heating, Cooling, Electric, Plumbing & Sewer in Lake Bluff, which is unrelated to the Evanston business.

But competition notwithstanding, Cahill said when they get very busy, “we’ll recommend Flader or Kerrigan or some of the other guys. And they’ll do the same for us.”

Kate Hardwick, administrative director of the John L. Ward Center for Family Enterprises at the Kellogg School of Management at Northwestern University, pointed out that multigeneration family businesses are a breed apart. The founders and their children can often manage for two generations, but the third generation is the “sticky spot. That’s when they need to put governance structures in place.”

Hardwick said four- and five-generation family firms are rare. “The Evanston community should be really proud to have supported these businesses over the generations.”