CHIMNEY SCAN
$250 — First Flue (Added to a Home Inspection)
$150 — Each Additional Flue
$500 — Standalone (includes $250 trip fee)
What a Flashlight Cannot Tell You
Every licensed home inspector in Illinois looks at chimneys. They inspect the exterior masonry from the roof, evaluate the firebox from the opening, check the damper, and note what is visible. A careful inspector with a good flashlight can see maybe three to four feet into the flue from below.
The average clay tile chimney flue in a Chicagoland home is 20 to 30 feet tall.
What lives in those other 25 feet — cracked tiles, separated mortar joints, creosote accumulation, partial collapses, blocked sections, and deteriorating liner walls — is completely invisible to a standard inspection. It is also where the most expensive findings hide, and where the safety risks originate.
A chimney scan inserts a camera into the flue. You see the full interior. We document what is actually there — not just what can be seen from the bottom of the opening.
What the IDFPR Requires — And What That Leaves Out
The Illinois Department of Financial and Professional Regulations (IDFPR) sets the Standards of Practice for every licensed home inspector in Illinois. Those standards require inspectors to evaluate the readily accessible and visible portions of the chimney — the exterior masonry, the chimney cap, the firebox opening, the damper, and the visible vent connector.
Inserting a camera into the flue is not required. It exceeds the standard home inspection scope. The IDFPR Standards of Practice define what inspectors must do — not what a thorough evaluation of a chimney actually requires.
The result is that most home inspectors do exactly what the standards require and nothing more. They note what they can see, recommend a chimney cleaning if there is visible buildup, and write "recommend evaluation by a certified chimney professional" in the report. That recommendation puts the investigation back on the buyer — after they have already closed.
The Chicagoland Factor — Why This Inspection Matters Here Specifically
If you are buying a home in Chicagoland, there is a specific type of chimney that deserves your attention before you close: the clay tile flue.
Clay tile is the most common chimney liner material in older Chicagoland homes. It was the standard for most of the twentieth century. Millions of homes in Cook, Lake, DuPage, McHenry, Will, and Kane Counties have clay tile flues — some of them original to homes built in the 1920s, 1930s, and 1940s.
Clay tile has one significant vulnerability: it does not tolerate the combination of heat stress, moisture, and freeze-thaw cycling that Chicagoland delivers every single year.
Here is what happens over time. A fire heats the clay tiles rapidly. They expand. They cool. They contract. Repeat that process hundreds of times over decades and the tiles develop stress fractures — hairline cracks that widen with each cycle. Water from rain and condensation enters those cracks. It freezes in winter, expands, and forces the crack open further. Mortar joints between tile sections soften and separate. Eventually tiles crack through completely, sections collapse inward, and gaps open in the liner that allow combustion gases — including carbon monoxide — to migrate into the chimney walls and potentially into the living space.
None of this is visible from the firebox opening. All of it is visible to a camera.
Two Hazards. One Camera.
A chimney scan is not just about finding expensive repairs. It is about finding two specific hazards that cannot be safely left uninspected.
Chimney Fire
Creosote is a dark, tar-like byproduct of burning wood. Every wood-burning fire deposits creosote on the flue walls. In Chicagoland's cold winters, more fires mean more creosote. The colder the flue temperature at ignition — which is the case every time a fireplace is lit after sitting cold — the more creosote deposits per fire.
Creosote is flammable. When it accumulates to sufficient depth and ignites, the result is a chimney fire — a fire burning inside the flue at temperatures exceeding 2,000 degrees Fahrenheit. A cracked clay tile flue cannot contain those temperatures. Neither can a flue with separated mortar joints. The fire transfers to the surrounding framing.
A buyer inheriting a fireplace with unknown creosote levels and unknown flue condition is inheriting an unknown fire risk.
Carbon Monoxide
The flue's job is to contain and exhaust combustion gases — including carbon monoxide — to the outside. A cracked or failed flue liner does not do that job reliably. Gaps in clay tile allow carbon monoxide and combustion byproducts to seep into the chimney walls and, in some configurations, into the living space.
This is not theoretical. Carbon monoxide poisoning from failed chimney flues is a documented cause of residential deaths. It is colorless, odorless, and requires a detector to detect — by which time the exposure has already occurred.
Knowing the condition of the flue before you purchase the home is the only way to know whether using the fireplace or gas appliance is safe.
What We Inspect — Component by Component
🧱 EXTERIOR MASONRY
We are already on your roof for the standard home inspection. The chimney exterior is inspected from close range — not binoculars from the ground.
We evaluate:
Brick and mortar condition — spalling brick, eroded mortar joints, and crumbling sections are documented. Mortar that has been worn below the face of the brick is called open jointing and allows water to enter and accelerate freeze-thaw damage
Chimney crown — the concrete slab that caps the chimney and directs water away from the flue opening. Crown cracks are one of the most common and most underappreciated chimney findings. A small crown crack becomes a large one after two or three Chicago winters, and water entry through a failed crown reaches the interior flue liner directly
Chimney cap — the metal cover over the flue opening that keeps rain, snow, birds, and debris out. A missing or damaged cap means the flue is open to weather and animals year-round
Chimney flashing — the seal between the chimney and the roof surface. Failed flashing is one of the most common sources of water intrusion in Chicago homes. We document flashing condition and identify any separation, lifting, or failed sealant
Leaning or settling — a chimney that has separated from the house or shows visible lean indicates foundation movement and requires structural evaluation
🔥 FIREBOX AND DAMPER
We evaluate:
Firebox walls — refractory brick and mortar joints for cracks, spalling, and deterioration. The firebox operates at the highest temperatures in the system. Damaged refractory materials in this area are a fire hazard
Smoke shelf — the horizontal surface behind and above the damper that catches debris and prevents backdrafts
Smoke chamber — the funnel section between the firebox and the flue proper. Unpargged or damaged smoke chambers with exposed rough masonry accumulate creosote faster and are more difficult to clean
Damper — operation, condition, and seal. A damper that does not seal costs energy every heating season. A damper that does not open fully restricts draft and creates smoke spillage into the living space
Gas log and gas insert components where present — burner condition, gas connection, and visible valve hardware
📷 THE FLUE SCAN — WHAT THE CAMERA FINDS
This is the part of a chimney evaluation that no standard home inspection provides. A camera is inserted into the flue from above or below and moved through the full length of the liner. Every section is documented. You receive video footage of the interior.
We look for:
Cracked clay tile — Any crack that passes through the full thickness of a tile is an opening between the flue interior and the chimney wall. Hot combustion gases and carbon monoxide can migrate through that opening. A camera is the only tool that reliably finds these cracks throughout the full length of the flue.
Separated mortar joints — The mortar joints between clay tile sections soften and open over time from thermal cycling and water exposure. An open joint is structurally the same problem as a cracked tile — a gap in the liner where gases can escape. In a long flue, there may be dozens of joints. A flashlight sees none of them.
Collapsed or displaced tile — A tile section that has fractured and partially collapsed inward reduces the effective flue diameter, restricts draft, and can block the flue entirely. A blocked flue cannot exhaust combustion gases. This finding is a no-use finding — the fireplace or appliance cannot be operated safely until the obstruction is cleared and the liner is repaired.
Creosote level and character — Creosote appears in three forms: a light, dusty deposit easily cleaned; a harder, tar-like coating that requires aggressive cleaning; and a glaze-hardened deposit that is nearly impossible to remove without specialized tools. The camera documents both the level and the character of any creosote throughout the full flue — not just what is visible from the opening.
Animal nests and debris — Birds, squirrels, and raccoons build nests in unprotected chimneys. A nest is a combustion hazard and a blockage. It also indicates the cap is missing or damaged — allowing ongoing weather exposure. We document any blockage and its location in the flue.
Metal flue condition — Prefabricated metal flues in factory-built fireplaces are inspected for corrosion, joint separation, and evidence of damage. Metal flues have a finite service life and are not field-repairable. A failed metal flue in a prefabricated fireplace system typically means the fireplace cannot be used until the flue is replaced.
🏠 MULTI-FLUE CHIMNEYS — EVERY FLUE MATTERS
Many Chicagoland homes have a chimney that serves more than one appliance. A typical configuration has the fireplace flue in the same masonry chimney as the furnace or water heater flue. Some older homes have three flues in a single chimney — furnace, water heater, and fireplace.
The furnace flue is the one most often overlooked. Most buyers think of the chimney in terms of the fireplace. The furnace flue — which exhausts combustion gases from a gas furnace or boiler every time the heat runs — receives far more use than the fireplace flue and is subject to significant moisture and condensation accumulation from the cooling of exhaust gases.
Our pricing structure reflects this: $250 for the first flue, $150 for each additional flue in the same chimney. We scan all of them. A chimney with three flues is evaluated as three separate systems — because each one is.
The Clay Tile Question Every Buyer Should Ask
If the home you are purchasing was built before 1980, there is a significant probability it has clay tile flues. Here is the direct question to ask the seller, in addition to scheduling the scan:
Has the flue liner ever been replaced or relined?
Most sellers cannot answer yes. Clay tile liners in Chicagoland homes are often original — 50, 60, 70, or more years old — and have never been inspected with a camera. A tile liner that has survived that many years of freeze-thaw cycles, Chicago winters, and sustained use is statistically likely to have some degree of cracking or joint separation. The question is not usually whether there is damage — it is how significant the damage is and what the repair options are.
If the seller can produce documentation of a camera inspection within the last few years with no significant findings, that is meaningful. If they cannot, the camera is the only way to know what you are buying.
What This Inspection Costs vs. What It Can Find
At $250 for the first flue, the math is straightforward.
Flue liner replacement in Chicagoland runs $2,500 to $7,000 depending on the liner type and chimney height. A complete chimney rebuild runs $4,000 to $20,000 or more depending on the extent of structural damage. Tuckpointing runs $500 to $2,500. Chimney crown repair runs $200 to $1,500.
Any one of those findings, documented before closing, is a negotiating point that is worth many times the cost of the scan. The same finding discovered six months after closing, when you light the fireplace for the first time in December, belongs entirely to you.
And the cracked tile with a carbon monoxide pathway — that finding has no price. That finding is about who is sleeping in the house.
A Straight Answer on When It Is Worth It
It is most worth it when: The home has a masonry fireplace in any home built before 1980. The home has a gas appliance — furnace, boiler, or water heater — vented into a masonry chimney. The seller cannot confirm any camera inspection within the last several years. There is visible creosote at the firebox opening. The chimney cap is missing or damaged. The home has been vacant for an extended period.
It is less critical when: The home has only a factory-built prefabricated fireplace with a metal flue that is documented as in good condition and within its service life. The home is newer construction with a modern direct-vent appliance that does not use the masonry chimney. The seller can provide documentation of a camera inspection within the past two years with no significant findings.
We will give you our honest read on which category your home falls into before you add this to your order.
312-544-9180
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