Chimney caps, crowns, chase covers and dampers for Kankakee County homes
The top of the chimney takes the weather for the whole house. A good cap and a sound crown are the cheapest insurance a chimney can have.
Chimney caps
An uncapped flue takes in a surprising amount of water. A 12-inch by 12-inch flue opening catches several gallons in a good Illinois storm, and that water lands on the smoke shelf, rusts the damper, and soaks the firebox. Caps also keep out raccoons, squirrels and, in our area especially, chimney swifts, which are federally protected and cannot be removed once nesting. We install stainless steel caps with a spark-arresting mesh, sized to the flue tile, and multi-flue caps that cover the whole crown on chimneys with two or three flues. Galvanized caps are cheaper and rust through in a few winters; we do not install them.
Chimney crowns
The crown is the concrete top of a masonry chimney. It should be at least two inches thick at the edge, overhang the brick by an inch or more with a drip groove underneath, and have a flexible joint around the flue tiles. Most crowns we see in Bourbonnais and Bradley were built as a thin mortar wash with none of that, and they crack within a decade. Hairline cracks get a flexible elastomeric crown coating. Broken or sunken crowns are formed and poured new.
Chase covers
Factory-built fireplaces sit inside a framed chase, and the metal lid on top is the chase cover. Original builder-grade covers are galvanized steel that rusts from the edges in, staining the siding and eventually letting water into the chase and onto the firebox. We fabricate replacement chase covers in stainless steel with a cross-break so water runs off, proper skirt height and a collar around the flue pipe. Rust streaks on the siding below the chimney are the tell.
Dampers
A throat damper is the cast-iron plate above the firebox. They warp, rust, and lose their seal, and an old one leaks heated air up the flue all winter even when closed. A top-sealing damper mounts on top of the flue, seals with a rubber gasket, and is opened with a cable from the fireplace. It replaces both the damper and the cap, seals far better, and keeps cold air and animals out. For homes that only burn a few times a season it is often the single best upgrade we can offer. We also repair or replace throat dampers where that is the right fix.
A half-open damper is why the fire never gets going
A damper that will not open all the way strangles the fire. Smoke has to squeeze past the plate, the flue never fills with hot gas, draft stays weak and the fire burns lazy and cool, which in turn makes more smoke. Many homeowners run their fireplace for years with the damper stuck at a third open and assume the fireplace is just a poor one. Rust, a bent handle linkage, a warped plate or a shelf full of debris behind it are the usual reasons, and all of them are fixable in a single visit.
The opposite mistake is just as common: starting a fire with the damper fully open and then closing it down early to “keep the heat in.” That is the moment creosote starts forming. The flue needs to be hot before the damper is throttled at all, and an open fireplace, unlike a stove, should run with the damper wide open for the whole burn. If your fireplace only warms the room when the flames are roaring, the damper position on the next cold start is the first thing to check.
Why we treat the top of the chimney as one system
A new cap on a cracked crown just channels water into the crack. A new crown with a missing cap still lets water down the flue. When we are on the roof we look at all of it: cap, crown or chase cover, the top courses of brick, the flashing, and the damper, and we recommend what actually needs doing in the order that protects the chimney. The masonry side of that work is on its own page.
Installation notes
- Caps are fastened to the flue tile with stainless screws, never just friction, so they stay put in a Kankakee County wind.
- Crown coatings are applied to a clean, dry crown after cracks are filled, with the flue tile joint bridged by a flexible sealant.
- Poured crowns are formed with an overhang and cured before the cap goes back on.
- Chase covers are measured on site to the sixteenth of an inch.
- Top-sealing dampers are matched to the flue size and tested from the fireplace before we leave.
Caps, crown coats, chase covers and damper installs are among the few jobs we can quote from a description and a photo. Starting prices are on the pricing page.
Smoke backing into the room instead of up the flue
When the chimney runs in reverse, smoke and carbon monoxide pour into the house instead of out the top. A missing cap that let the flue fill with debris, a cold flue plug, a tight house with the range hood running, or wind driving down a short or poorly capped chimney all cause it. A good cap and the right damper are often the fix.
Signs right now: smoke rolling out when you light up or mid-burn, a smoky smell spreading through the house, backdrafting that starts the moment a kitchen or bath fan runs, or staining above the fireplace opening.
What to do: open a window near the fireplace, switch off every exhaust fan, confirm the damper is fully open, and if the room fills with smoke put the fire out and ventilate. If a carbon monoxide alarm sounds, get out and call 911.
Questions we hear about this
Do I really need a chimney cap?
Yes. It is the least expensive part of the chimney and it prevents the most expensive damage: water in the flue, rusted dampers, animal nests and blocked flues.
What size cap does my chimney need?
Caps are sized to the outside dimensions of the flue tile, or to the whole crown for a multi-flue cap. We measure on the roof so it fits the first time.
How do I know my crown is cracked?
Water in the firebox after rain, white staining on the top courses of brick, and pieces of concrete on the roof are the usual signs. From the ground it is hard to tell, which is why it is part of our annual inspection.
What is a chase cover and why is mine rusting?
It is the metal lid on a prefab chimney chase. Builder-grade covers are galvanized and rust from the edges. Rust streaks on the siding mean it is time to replace it in stainless.
Is a top-sealing damper better than a throat damper?
For most homes, yes. It seals tighter, keeps out animals and rain, and replaces the cap. The exception is a fireplace with a gas log set that requires the damper to be fixed open.
Can a cap cause my fireplace to smoke?
A cap with a clogged screen or one too tight to the flue can. We size caps with enough clearance and check draft after installation.
Do you remove birds or animals from chimneys?
We remove nests and debris once the animals are gone and install a cap so it does not happen again. Chimney swifts are protected while nesting, so timing matters; we will tell you when we can legally clear the flue.
How long does a crown repair take?
A crown coating is a couple of hours. A poured crown is about half a day plus curing time before the cap is reinstalled.
Protect the top of your chimney this season
Call and you will talk to a person who can put you on the schedule today.
Call (815) 449-4264