
Just up the block from Soul & Smoke and not far from Suds Car Wash and the Double Clutch brewery, Paul and Kimberly Boynton run their thriving concrete business, Kelvin Co., out of the first floor of a frame two-flat on Ashland Avenue. Their backyard is full of trucks, backhoes, metal rebars and wood for concrete formwork. They rent out the second floor and live elsewhere.
Paul says he has been around the concrete business since he was 9, if he counts those early years when his contractor father, Bernard (“Bernie”) Boynton, let him come to job sites and ride around on the trucks. Paul learned how to do framing work when he was 12.
“It was all hand work back then,” he said. “No power tools … it was much tougher to knock out an old driveway manually than with a Bobcat.”
As a kid, Paul was good in math, but he did not like reading. Among his summer activities were wrestling and football. He graduated from Evanston Township High School in 1986 and went to work for Freise Construction, a local general contractor. After 12 years there he worked at Pinel Andrews Construction Corp., another local contractor, for six years.
Getting into the concrete business
In 2004 Paul got the opportunity to buy the local concrete business Lane & Sons, owned by John Lane, also an Evanston resident. Lane worked for Paul for a year and then retired and built his family a home in Mississippi. Paul is still in touch with Lane, who is now in his late 80s.
The name “Kelvin” relates to its definition: A kelvin is the primary unit of temperature in the International System of Units. In the concrete business, the temperature of the air plays a crucial role in how long concrete takes to set. Many customers think Paul’s last name is Kelvin.
The hard facts on concrete
Concrete is everywhere. But most of us don’t know about the complex process of getting it to where we see it as a finished product in our sidewalks, driveways, and basement walls and floors.
Concrete is composed of water, cement, aggregates and additives and is trucked from the concrete plant to the job site in a concrete mixer truck. The concrete job site workers guide the liquid concrete as it pours from the mixer truck into the prepared metal or wood formwork. Doing accurate calculations of how much concrete to order and exactly when it should arrive at the job site takes years of experience.
The increasing demand for concrete, supply chain issues because of a global cement shortage and recent labor shortages have affected both large and small concrete businesses, Paul said.
During summer 2022 a strike by Local 150 of the International Union of Operating Engineers, which represents loaders of stone and operators at concrete and asphalt plants, slowed down work all over the Chicago area, including Evanston street repairs and Kelvin Co. projects. Now there is a built-up demand for concrete on commercial and public projects like highways, and the supply chain is not keeping up, Paul said. Often those projects have higher priority than the smaller projects of a company like Kelvin.
Kelvin’s concrete supplier, Ozinga, recently informed its customers that it has had to close its plants on Saturdays, and it has started taking fewer orders and limiting the amount of concrete per customer. “We need to pump the brakes in order not to put ourselves in a position of running out of material midpour,” Justin Ozinga said.
Running the business
In this family business, Kim runs the office. She said she learned many of the skills needed to run the business from Janet Freise of Freise Construction.
The most challenging parts of running the business, Kim said, are seeing her husband “stressed out about work, and the turnover in employees.”

Several Kelvin employees have been with the company for many years. Foreman Hector Garcia has been with the firm since 2004 and concrete finisher Ruben Moreno since 2010.
Kelvin’s clients include general contractors, landscape contractors and homeowners. The company stays busy in the winter with interior concrete projects such as lowering basement floors in older homes, concrete countertops and other work that is not affected by outdoor temperatures. A backup business in the winter is snow plowing – but with climate change, there is less snow to plow, Paul said.
To adjust for supply chain issues, Kelvin’s contracts are only good for 60 days. If concrete prices increase after that, the client has to absorb the additional material
costs. Labor cost stays the same.
Paul admits his job is stressful, especially during periods when material supply chains are challenging. “I’ve learned to be patient,” he said. (“He’s working on it,” Kim said.)
Community involvement
Kelvin Co. provides concrete foundations for the homes built by Evanston Township High School’s Geometry in Construction classes. Since 2013 these interdisciplinary classes have involved students in all aspects of design and construction of 3-bedroom, 2-bath affordable homes for Evanston families. The homes are built at ETHS and then moved to their final locations. The City of Evanston and Community Partners for Affordable Housing are also partners in this program.
Although the Boyntons went straight to full-time jobs after graduation from ETHS, both support the idea of community college programs that prepare students for trades.
Paul is on the advisory board of an apprenticeship program at Oakton Community College that connects students as interns to various trades. He said Kelvin Co. is always willing to train a new employee, although it is helpful if the trainee has had some background in construction.
This article came just in time. My wife and I have been wracking our brains trying to remember the name of this company. Kelvin poured a new walkway in our home in Evanston many years ago (did a fantastic job, by the way).
We need some concrete work done at our new home in Morton Grove, so now we know who to call. Thanks Roundtable.
Also, little known fact—these guys have fun! We watched them pour our slab and enjoyed listening to their banter and jokes, all while doing a great job. Thanks for the backstory!
Thank you for this article highlighting the people and the hard work of this black owned Evanston business. Please publish more articles about Evanston businesses that do not have a public commercial street front face.
Very interesting to learn backgrounds of our local businesses and challenges they deal with.
Great article. Thank you.