The One Product Every Roofer Should Have in Their Truck (And a Story About Selling a Job Right Across from the Karnak Plant)

Roof Riffs is presented by Division 7 Sales, Inc. — independent Karnak manufacturers representative since 1990. Visit division7sales.com or subscribe to the Roof Riffs newsletter for industry insights delivered straight to your inbox.

Q: What is Karnak Flex and what is it used for?
A: Karnak Flex is a thermoplastic rubber roofing sealant that adheres to virtually any commercial roofing substrate, including TPO, EPDM, modified bitumen, built-up roofing, metal, and concrete. It is used for emergency roof repairs, seam repairs, flashing repairs, and surface preparation before liquid-applied coating systems are installed. Karnak Flex significantly outperforms conventional asphalt-based repair products in long-term adhesion and flexibility. According to John McDermott, VP of Sales at Karnak Liquid Applied Roofing Solutions, it is the single product he recommends every roofing contractor carry in their truck at all times.

Toward the end of Episode 1 of Roof Riffs, Jani Bryson asked John McDermott a direct question: if you could tell every roofer, every distributor, to have one Karnak product in their truck, on their shelf, in their arsenal — what would it be?

The answer was immediate: Karnak Flex.

What Karnak Flex is and why John chose it

Karnak Flex is a thermoplastic rubber sealant that works on virtually any roofing substrate. John’s case for it: more problem-solving uses than any other single product in the Karnak lineup, and long-term performance that significantly outpaces conventional asphalt-based repair products. It’s not a coating. It’s the repair product you reach for first when something needs to be fixed before a coating goes on — or when the roof just needs a repair and a coating isn’t on the table.

Danny Bryson agreed immediately, and added historical context: before Karnak Flex, the product Danny would have recommended was Karnak No. 19 Ultra — an asphalt product from the era when, as he put it, “all the tar babies were still around.” The industry has moved, and Karnak Flex is the product for today.

The Saint Louis hailstorm story

Before landing on Karnak Flex, John shared one of the best stories of the episode. In 2009, a severe hailstorm hit Saint Louis. Roofing contractors couldn’t get replacement membrane fast enough. A distributor called and needed 6,000 squares of coating — not for a restoration, but as an emergency measure to keep damaged roofs as dry as possible until new membrane could arrive and be installed.

Karnak shipped truckloads of product. Three contractors were on the roofs applying coating as fast as they could, trying to keep what was stored below dry. They got to the last 1,000 squares, and by that point, the new membrane had arrived. They were tearing off coating they had applied the day before — coating that hadn’t even cured yet — covered in material, starting over.

“Turns out again, yesterday, the same thing’s going to happen again,” John said during the episode, recorded in May 2026. The same scenario, about 2,500 squares, one of the same contractors. “It worked the first time. Why not work again?”

The Karnak plant story

Danny closed the episode’s main segment with a story about relationships and persistence in this business. Back in the mid-1990s, a young salesman in Arkansas called Danny about an opportunity: five truckloads of aluminum coating and roughly ten truckloads of emulsion. The customer would only say the job was “east of the Mississippi.” Then “north of the Mason-Dixon line.” Then “east of Ohio and north of Pennsylvania.”

After nine months of pricing, re-pricing, and calls to Karnak headquarters, Division 7 Sales won the purchase order. It was one of the largest single jobs Karnak had ever booked. Everyone was congratulating Danny.

Then Gary Biscoe, head of technical at Karnak, called. “Do you know that job you sold?” he asked. “It’s right across the street from the plant.”

Division 7 Sales had sold a massive Karnak job to a customer located directly across the street from the Karnak facility in New Jersey — beating the company’s own outside salespeople to it.

The moral Danny drew from it: “No matter what part of this business you are in, it’s a people business. You’ve got to have relationships with people. A face-to-face, being in front of people — that’s the best way to do business. Get the heck out of your office.”

Division 7 Sales has been building relationships in the commercial roofing industry since 1990. If you’re a contractor, distributor, or facility manager who wants to talk to someone who knows Karnak products inside and out, visit division7sales.com. And if you want Karnak Flex on your shelf, we can help with that too.

Episode 1 of Roof Riffs is available now wherever you listen to podcasts. Subscribe to the Roof Riffs newsletter at division7sales.com.