A cap is a small, simple-looking part that does a genuinely important job: keeping rain, embers, and animals out of the flue while letting smoke and combustion air move freely. Getting the size and material right matters more than it looks like it should.
Why precise sizing actually matters
A universal-fit cap that is even slightly too small rocks in the wind and leaves a gap animals or rain can exploit. One that is too large can restrict draft and cause a smoky fireplace. We measure the actual flue opening rather than guessing from a standard size chart.
What installation includes
Frequently asked questions
Do I really need a cap if I never use the fireplace?
Yes, maybe more so. An unused flue is exactly the kind of dark, sheltered opening that attracts nesting animals, and an uncapped flue also lets rain in year-round regardless of use.
Stainless or galvanized, does it matter?
Stainless costs a bit more upfront but resists rust for far longer in a humid climate, which makes it the better long-term value.
Can a cap actually cause smoke problems if it’s wrong?
Yes, an oversized or poorly designed cap can restrict draft. Correct sizing avoids that entirely.
How long does installation take?
Most single-flue cap installations are a same-visit job, typically under an hour once we’re set up at the flue top.