Check the chimney with care
You can clean and repair your own chimney with low-cost items from the hardware store.
The New York Times
Here’s one for the annals of homeowner negligence: As of last month, my chimney had gone eight full years without being inspected, much less cleaned. For all I knew, a few generations of squirrels had summered in my bricks before fleeing at the first scent of smoke.
In those years, we had probably burned 50 fires, but none since March 2011. But with Hurricane Sandy approaching, I knew I would likely need the fireplace for light, heat and maybe some cooking duties. Could I start it up once more without burning the house?
To answer that question and others, I called on Ashley Eldridge, the director of education for the Chimney Safety Institute of America; and John Gulland, writer and manager of WoodHeat.org, a site devoted to wood-heat systems.
With a few kernels of knowledge and a handful of low-cost items from the hardware store, homeowners can keep a chimney healthy between cleanings and keep the home’s heating system in good repair, they said.
My experts also suggested a cheap way to make a great backyard fire pit, but more on that later.
My most pressing concern was whether I could light the first fire of the season without fear. I had ignored stories about chimney safety because my chimney looked fine from the outside, and it wasn’t belching smoke into our living room. People who live in similar ignorance are taking a risk.
Creosote can build up in a flue if you burn enough smoky fires, which come from wet wood, or fires that smolder before catching. This tarlike substance can catch fire with an inferno so intense that flammable materials abutting the chimney can also ignite.
“It just goes nuts in that chimney,” Gulland said. “All the heat produces a strong draft, so it sounds like a jet engine or a railroad train. It’s terrifying.”
The likelihood of a house fire depends on how closely your home’s builder adhered to safety codes. Some second-story floor beams, for instance, are anchored in the chimney. If they were placed without careful regard for building codes, they could encroach too closely on the flue and ignite in a creosote fire.
A good chimney sweep, Gulland said, “will have a radar for screw-ups like that, because there’ll be hints.” And keeping the flue clean, he added, minimizes the risk that such factors will come into play.
Eldridge suggested having a chimney inspected annually by a sweep who carries a certification from his organization, in that way ensuring the sweep meets training, educational and ethical standards. The CSIA.org site includes a searchable index of such sweeps.
Like most people, I’ve heard horror stories about swindles where a low-cost chimney sweep with a high-pressure sales pitch will identify costly phantom problems in places you can’t see.
To find a trustworthy sweep, Gulland suggested asking friends and avoiding low bidders.
I had five days before Sandy arrived, and a very low likelihood of finding a sweep before then. I needed to do an inspection on my own, but I had no idea what to look for.
Gulland and Eldridge suggested getting a pair of safety glasses, a mirror and a strong flashlight, and starting at the bottom.
And that doesn’t mean the fireplace.
A chimney often has two flues, one for the fireplace and one that reaches to the basement, where, in homes heated with water, it connects to the boiler’s exhaust pipe.
Multi-flue chimneys commonly terminate in a chamber that catches soot from a “clean out” passage at the bottom of the fireplace. That soot can build up so much that it interferes with the boiler’s airflow. A little doorway, commonly found on the chimney and below the exhaust pipe, is there for removing soot.
I extracted at least 20 pounds of the stuff, and noticed gaps in the mortar connecting the exhaust pipe to the chimney. I tried not to think about the fumes that were escaping into my basement.
Next, I checked the fireplace itself. I slipped on goggles, opened the damper and, for the first time, checked the flue.
It wasn’t so bad. I scraped the surface with a poker, which revealed less than a half-inch of soot. I ran my finger across it and found a soft, sooty form of creosote rather than the more dangerous tarry variety.
My next bit of do-it-yourself maintenance was clearly not meant for the masses. I got up onto my second-story rooftop with roofing cement and silicone caulking seal. Gulland suggested sealing any gaps between the metal flashing and the chimney so water did not creep into the seams between the chimney and the house.
I also saw that my chimney cap had been installed with wire mesh, to keep critters out. Lovely. I’ve been looking at the mesh for 12 years and never really registered its existence.
Gulland and Eldridge both strongly recommend chimney caps, to keep animals, foliage and rainwater out. I removed the cap and found the boiler flue clear, and the fireplace flue looking the same as it did from the firebox.
Before I lit a fire, I bought a creosote sweeping log ($20), which my local hardware- store manager recommended as a way to reduce creosote. I didn’t notice much of a difference in the soot after burning it, but I felt marginally safer, and Eldridge said it would make the chimney easier to clean, should I ever find a sweep.
My last order of business was building a fire pit, because my family had been requesting one for years. I assumed it was an arduous and expensive job. It was neither.
Gulland said the most common mistake with fire pits is that people make them too big. “Make it tiny,” he said. “A proper campfire, which is really what you’re building, is only 18 to 24 inches in diameter, and it’s just as pretty and less intimidating if it’s small and bright.”
I spent around $35 on 27 bricks from Lowe’s and a $17 grate from Home Depot, and assembled the pit in 20 minutes. My family was thrilled.
When Hurricane Sandy knocked out our electricity, the fireplace provided much-
needed warmth, light and hot pasta. The fire pit will get its turn soon enough. And the trees sprawled across our property should keep both busy for a few seasons at least.