Fireplace and smoke problems
Chimney cap vs. chase cover vs. crown
Three different parts protect the top of a chimney, and they are often confused. Knowing which one you are looking at makes quotes and symptoms easier to read.
Short answer. A crown is the masonry slab on top of a brick or block chimney. A cap sits over the flue opening and keeps rain, animals and debris out. A chase cover is the metal lid on a framed chimney chase. A masonry chimney has a crown and may have a cap. A prefabricated chase has a chase cover.
Three parts, three jobs
| Part | Where it is | What it does | Typical material |
|---|---|---|---|
| Crown | Top of a masonry chimney, around the flue | Sheds water off the top of the brick and keeps it out of the masonry | Cement-based or poured masonry |
| Cap | Over the flue opening | Keeps rain, animals and debris out of the flue | Metal, often stainless steel, with a screened opening |
| Chase cover | Top of a framed, often siding-clad chase | Covers the whole top of the chase and sheds water | Sheet metal |
Which one does your chimney have?
- Brick, stone or block all the way up: it has a crown, and may or may not have a cap.
- Box on the roof covered in siding or stucco, with a metal pan on top: it has a chase cover, and usually a cap on the flue.
- Metal pipe sticking out: this is a different system; check the manufacturer.
Symptoms at the top
| What you see | Possible cause | Next step |
|---|---|---|
| Cracks across the top of the masonry | Crown deterioration | See cracked crown guide |
| Rust streaks running down a chase | Chase cover corroding or ponding water | Have the chase cover inspected |
| Birds or animals in the flue | Missing or damaged cap | Add or replace the cap |
| Water in the firebox after rain | Any of the three; also flashing | Inspect the top and the flashing |
| Cap loose or leaning | Fasteners or mounting failed | Have it checked, especially after wind |
What to ask a contractor
- Which part is failing, and how do you know?
- Can I see photos from the roof?
- Is a repair or replacement recommended, and why?
- Does the cap or chase cover need to fit this particular flue or chase?
Common misconceptions
"A cap and a crown are the same." They are separate parts. A cap does not replace a failing crown.
"A cap solves a leak." It only helps if water is coming down the flue. Leaks at the crown or flashing need those parts addressed.
"Any chase cover will do." It has to cover the chase properly and shed water.
See also
Read cracked chimney crown and water coming into the chimney.
About this guide. Published by Dr. Sweeper as general homeowner education, last updated October 1, 2026. Sources are linked where they are cited. What applies to your home can depend on your local building code, your appliance and its manufacturer's instructions, and the actual condition of your chimney, so this guide is not a substitute for an inspection.
If you need help
Related services
Chimney caps
Rain and animal protection at the flue top.
Learn moreChase covers
Covers for framed chimney chases.
Learn moreCrown repair
Repair of the cement or masonry top of the chimney.
Learn moreCap Replacement
Rusted, bent or missing caps.
Learn moreChase Cover Replacement
Stop leaks into a framed chase.
Learn moreChimney Chase Repair
Framed chimneys: water, rot and covers.
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Frequently asked questions
Does every chimney need a cap?
Covering the flue opening is a common recommendation to keep out rain and animals. Ask what suits your chimney.
Can a chase cover be repaired?
Small defects can sometimes be sealed. Heavy rust or ponding often calls for replacement.
Will a cap stop downdrafts?
Not always. Draft problems have several possible causes.
Not sure what is on top of your chimney?
Call or book a visit and we will check it.