There is a part of your fireplace you have probably never seen and may never have heard of, and in a house built in the 1950s there is a fair chance it was left unfinished. AM Chimney Sweep cleans, inspects and repairs chimneys in Paramus, and the smoke chamber is where we find a lot of the trouble.
Where it is and what it does
The smoke chamber sits directly above the damper. It is the space where the wide fireplace opening narrows down to the much smaller flue, shaped like an upside-down funnel. Its job is to gather smoke from the full width of the firebox and guide it smoothly into the flue.
How it was typically built
To make that funnel shape, the mason stepped each course of brick inward a little over the one below, a technique called corbeling. The result inside is a staircase of brick edges. In a great many fireplaces the steps were simply left that way, rough and with open mortar joints. Current standards call for the inside of a smoke chamber to be smooth.
Why Paramus
Census Bureau estimates show that about a third of the homes in Paramus were built in the 1950s, and the large majority of the borough’s housing is single-family houses. A stepped, unparged smoke chamber is a common finding in fireplaces of that period.
Source: U.S. Census Bureau, American Community Survey 2020–2024 five-year estimates.
What a rough smoke chamber causes
- Smoke in the room. Each step creates turbulence. The smoke tumbles instead of rising, slows down, and some of it rolls back out of the fireplace opening.
- Heavy creosote in one place. Slow, swirling smoke leaves deposits on every ledge, and the corners of a stepped chamber are hard to reach with a brush.
- Heat where it should not be. Gaps in the brickwork let heat and gases through to the masonry behind, close to the framing of the house.
How it is recognized
- The fireplace smokes even though the flue has just been cleaned and the damper opens fully
- Smoke stains on the face of the fireplace above the opening
- A sweep finds thick buildup just above the damper while the rest of the flue is fairly clean
It is confirmed with a camera or a mirror and light through the damper. We show you the pictures.
The repair: parging
Parging means coating the inside of the smoke chamber with a high-temperature refractory mortar. The coating fills the gaps, covers the steps and leaves a smooth, sealed surface that smoke can follow. The chamber is cleaned first so the material bonds, then the coating is applied through the fireplace opening or from above, depending on access. The steps are set out on our smoke chamber parging page.
What parging will not fix
It is worth being clear about this before you spend money.
- A flue that is too small for the fireplace opening
- A chimney that is too short or is sheltered by a taller roof
- A house that is short of air because of tight construction or a strong kitchen exhaust fan
- A cracked or unlined flue above the chamber, which is a flue repair or liner job
That is why we inspect the whole system first. Parging is recommended only when the smoke chamber is actually the cause.
Other chimney work in Paramus
Chimneys of this age tend to need the same few things: a sound crown, a cap, and repointing of the top courses. We also provide regular chimney cleaning.
Schedule service
Call (862) 225-6529 or send a request online and tell us when the fireplace smokes: at start-up, on windy days, or all the time. To see this repair on a real job, read our smoke chamber case study from Morristown, or browse Our Work.