Aroma Park fireplace that smelled sour after every wet week: the ash pit was holding river water

By Jacob Dove, Friendship Chimney Sweep

A clean flue that still smelled like a wet campfire

The call came from a brick ranch a few blocks back from where the Iroquois runs into the Kankakee. The complaint was specific: a sour, smoky smell in the family room that showed up after rain and on muggy days, even though nobody had burned a fire in months. The flue had been swept the previous winter, so the owner assumed the sweep had missed something.

It had not. I ran the camera up the flue and the tiles were clean, the smoke chamber was brushed, and the damper closed the way a thirty-year-old throat damper closes, which is to say mostly. What gave it away was the ash dump, the little cast iron trapdoor in the floor of the firebox. When I tipped it open, the air coming up out of it was cold, damp and strong. Odor rides on moisture, and that draft was carrying the smell of every fire the house had ever had.

After 29 years in the trade I check the ash pit on every sweep, because it is the part of a masonry fireplace that almost nobody remembers exists. In a house near two rivers, it matters more than usual.

What was sitting at the bottom of the chimney

The ash dump drops into a hollow shaft inside the chimney base, and that shaft is emptied through a small steel cleanout door, usually in the basement or on the outside of the chimney near grade. This one was in the basement, behind a shelf of paint cans. The door had rusted through along its bottom edge and the frame had pulled loose from the mortar.

Behind it was decades of ash packed nearly to the top of the pit, and the bottom third of it was soaked into a grey paste. The owner told me the basement had taken a few inches of water during a high-river spring some years back. Water had wicked into the ash through the failed door and the block around it, and ash holds moisture the way a sponge does. Wet wood ash is also strongly alkaline, which is why the steel door and the lower mortar joints looked as bad as they did.

So the mechanism was simple. In humid weather the damp ash gave off odor, the house pulled a little air down the chimney and up through the ash dump, and the family room got the result. Sweeping the flue again would never have touched it.

How we cleared it and kept the water out

We emptied the pit completely with a HEPA vacuum and hand tools, bagged the wet ash, and brushed the shaft walls down to bare masonry. With the pit empty I could inspect the base of the chimney properly, which is part of a Level 1 inspection under the NFPA 211 standard we work to: the cleanout has to be accessible, the door has to close tight, and the masonry around it has to be sound.

• New cleanout door. We set a new cast iron door and frame in fresh mortar so it seals. A loose cleanout door on a chimney base is also an air leak that weakens draft.
• Repointed lower joints. The softened joints around the opening were raked out and repointed.
• Ash dump door. The trapdoor in the firebox floor was warped, so we replaced it with one that sits flat and closes off the pit.
• The damper. We talked through a top-sealing damper for later, since a tighter seal at the top reduces the downdraft that carries odor into the room.

The owner asked about cost before we started. Our pricing is published on the pricing page, and I walked through it at the kitchen table before any work began. Friendship Chimney Sweep is Insured & Bonded, and we are on the phones 7am to 9pm, seven days a week.

My advice for anyone in Aroma Park whose basement has ever taken water: have the ash pit emptied and the cleanout door checked at your next sweep. Ash that stays dry can sit for years without trouble. Ash that has been wet once will keep smelling until it is gone.

If this sounds like your house: we handle chimney sweeping and ash pit cleanouts across Kankakee County, and our Aroma Park page covers what we usually find there. Call (815) 449-4264, 7am to 9pm, any day.

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