Conshohocken’s ‘Chimney Scientist’ shares advice on fireplace safety in your home

Winter officially began Wednesday, Dec. 21 and more homeowners across the region are lighting their fireplaces for the first time since last season.

Joseph Ochal, a chimney sweep who founded the Conshohocken-based company Chimney Scientists in 2014, shared what homeowners should know before they cozy up next to their crackling logs.

Ochal talked about his own experiences and suggested a cautionary title for this story: “Chimney sweep almost catches his house on fire with a woodstove.”

» READ MORE: What you need to know to keep your fireplace and chimney safe for use

The following interview has been condensed and edited for brevity and clarity.

Have your fireplace and chimney cleaned or inspected annually. And get a camera inspection of your chimney.

Chimney cleanings are helpful to reduce soot buildup for a wood fireplace, but there can be holes and cracks inside the chimney where fire can escape into the chimney cavity and potentially drywall of the home. So a camera inspection is just as important as getting it cleaned.

The number-one thing is making sure you have dry wood. When you’re buying wood from a landscaper or a wood provider, it’s not always fully dry. If you’re hearing your wood hissing when you’re burning it, that is water inside the plant cells boiling. Versus crackling, which is air inside the plant cells expanding and exploding them.

Wet wood turns into smoldering fires. And smoldering fires produce a lot of smoke. Smoke turns into creosote in the chimney, which is a flammable tar that can catch on fire.

The U.S. Environmental Protection Agency’s Burn Wise program recommends that wood should be split, stacked, and covered for 12 to 18 months before using.

Every day, we see holes inside the chimney called missing mortar joints. These holes in a masonry chimney start to form after 20 to 30 years and could be a hazard if not repaired. They can allow fire to escape into the chimney cavity and potentially drywall.

Just because previous homeowners used the fireplace doesn’t mean that it’s in good condition. Many times, we put a camera inside the chimney and not only are there holes, but we can see charred wood framing and drywall that’s either been smoldering or caught on fire. Homeowners have been told that their chimney had been maintained, and that’s not always the case.

There’s a chemical you can spray into your fireplace that converts sticky, glazed creosote into a powdery, less flammable creosote. It’s called Cre-Away chimney cleaning powder, and we recommend it to our customers who use their fireplaces multiple times a week just as a precaution.

Things as simple as gas logs — logs that you put inside the fireplace that don’t produce soot or creosote — can catch the house on fire and kill homeowners. People don’t typically burn a wood fire for more than three to four hours, and the heat fluctuates. A gas log fire is very easy to turn on, it’s a constant temperature, and people will burn those for much longer — eight hours, 10 hours. And if they run out of power, they’ll use them as a heat source and run them overnight.

The concern is the gas logs create so much heat they can heat up the masonry chimney. And if there’s any holes in the chimney, where wood framing is touching the chimney, it could potentially catch on fire.

What I have in my own home is something called a Chimfex. It’s a chimney fire-extinguishing road flare. It puts a chemical in the chimney that sucks all the oxygen out of it, and that starves the fire and can put it out. This is great for woodstoves or open burning fireplaces that have glass doors.

If there’s a fire burning inside your chimney, that typically sounds like a freight train going through your house. It’s very scary. There’s usually also a fire going in the fireplace when this happens. So you take the road flare, engage it by flicking it kind of like a match, and then throw it into the fire and close the doors.

I try to keep a flare close to where I keep my fireplace products near my fireplace. It can prevent a lot of damage.

A couple of weeks ago, I started a fire in my woodstove, and smoke was coming into the room, which was very strange. I knew that I was probably having a chimney fire. I went outside and saw billowing black smoke coming out of the chimney.

Then I take a flare, and I throw it into the fireplace, and I hear it start to kind of go off. I go outside, and I see flames coming out of the chimney. Then the flames go out, and there’s just smoke, not as much as before.

From inside my house, I can tell the fire’s out. Luckily, I installed a stainless steel tube inside the chimney, which is built to withstand multiple chimney fires. So I knew there were no holes in my chimney where fire could get into the drywall.

This whole experience happened in less than two minutes. So it was scary because of how quickly it happened.

Last year, I didn’t clean my chimney ‘cause I was just busy and lazy like everybody is. And then this year, I was like, “I’ll get to it.” I figured it would be very, very clean, because I burn such dry wood. Well, I didn’t realize that I had a lot of creosote in my chimney, and it caught on fire. So sometimes a situation can surprise you. And having that road flare was a real life saver.

If you don’t have a stainless steel liner in your chimney and you don’t have your chimney inspected, if you use that road flare and it turns out there are holes in the chimney, it may have put out the fire inside the chimney. But there may be another fire going on or smoldering behind the drywall that you’re not aware of. It’s important to call the fire department as a precaution.