Contractor Finds Easier, Safer Way to Install Roof Flashing

Flashing product boosts safety, productivity by rendering risky rooftop work obsolete

Contractor Finds Easier, Safer Way to Install Roof Flashing

Examples of the different stacks that can be installed from inside buildings using the Kozy Kollar exhaust vent and stack-pipe flashing. (Photo courtesy of Kozy Kollar)

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Tim Coyle remembers all too well the “good old days” of installing roof flashing for vents and stack pipes: Prop up a 36-foot extension ladder. Have someone hold the ladder. Climb up to the roof. Install the flashing. Have a person inside the attic push the pipe through. Rinse. Repeat.

“It was quite time consuming and required a lot of labor,” says Coyle, the owner of Tim Coyle Plumbing & Heating in Atkinson, New Hampshire. “And it could be pretty nerve-wracking, too.”

Then Coyle discovered the Kozy Kollar, a vent-and-flashing system that can be installed from inside a building. And he hasn’t been on top of a roof to install flashing in more than 20 years, he notes.

“If you asked me, it has changed the industry,” says Coyle, whose company primarily does new-construction plumbing. “Houses are getting taller and steeper, so it’s getting more and more dangerous to go up on a roof. And half the year around here it’s cold and windy. So there’s a lot of risk of someone getting injured.

“I’ve had a few scary moments myself,” adds Coyle, who established his company in 1994, employs seven people and runs three service trucks, all Isuzu NPRs with 14-foot box bodies made by Morgan Truck Body. “At one point, I just froze up while on a roof. I asked myself, ‘What am I doing up here? Am I a roofer or a plumber?’

“But I don’t have to worry about that anymore,” he notes. “I really can’t imagine working without the Kozy Kollar — it’s pure genius.”


There are two kinds of Kozy Kollar available: one for exhaust vents and one for 2-, 3- and 4-inch-diameter PVC pipes. Both can be installed on flat roofs; the exhaust flashing has an unlimited roof-pitch range, while the pipe flashing works on roofs with up to a 14:12 pitch. They’re suitable for conventional shingles, architectural shingles and metal roofs.

Coyle says virtually anyone can install a Kozy Kollar in about 15 minutes. That’s a far cry from taking, say, closer to 1 1/2 hours for a typical flashing installation. “I couldn’t plumb 100 homes a year without the Kozy Kollar,” he says. “Good labor is hard to come by these days, so you need be as productive as possible. This frees up two guys to do something else. The time it saves and the risks it reduces are incredible.”

Installation is a fairly simple process. After determining the pitch of a roof, select the appropriate template — included with each Kozy Kollar. Square the template between two rafters and trace it onto the plywood underlayment. Then cut out the marked template with a reciprocating saw. (Coyle technicians use SAWZALLs made by Milwaukee Tool.)

After inserting the included bolts into the unit (seven bolts for the exhaust hood and six for the stack-pipe units), apply the included sealant to the built-in groove on the bottom of the unit. Then pass the Kozy Kollar through the hole and position it flush with the roof to create a weather-tight seal; the bolts will hang down along the edges of the template hole.

Only two steps left: Slide the two mounting back plates onto the bolts, then tighten the included nuts onto the bolts to 3 ft-lbs of pressure. (Be sure to read the installation instructions for more specific details or watch installation videos at

“Everything is done from inside the attic,” Coyle says. “I’ve even installed them while it’s raining or snowing and in hot weather or cold weather — it doesn’t matter.”


Coyle estimates he’s installed more than 1,000 Kozy Kollars over the years and says he’s encountered only a handful of callbacks — and those were related to installation errors, not a defective product.

“Last year we put in 250 Kozy Kollars, usually two on each home — one for the stack pipe and one for a radon vent — and had zero callbacks,” he says. “That’s important because callbacks are a killer in this industry.”

A Kozy Kollar costs about $57. Coyle says that’s a small price to pay compared to tying up three guys for up to 1 1/2 hours, plus running the risk of someone falling off a roof.

A plumber for 30 years, Coyle admits he was a bit skeptical when he first heard about the product. “I’m not much into change,” he says. “I took a look at it and said, ‘How is this ever going to work?’

“But now everyone in our area uses them,” he says. “If you’re in new residential construction, I’d highly recommend them — they’re as important as a Channellock to a plumber. They’ve been a lifesaver, a timesaver and a moneymaker, if you ask me.” 


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