By Johnathan Mason, Ace Chimney Service.
Of all the parts on your chimney, the cap is one of the smallest and one of the easiest to overlook — yet in Lake in the Hills it does some of the most important work. A good cap keeps rain, animals, and stray embers where they belong, and a missing or damaged one quietly leads to some of the most expensive repairs we see. With 29 years in the trade, our insured and bonded team checks the cap on every visit.
What does a chimney cap actually do?
A chimney cap is the covered screen that sits on top of your flue, and it earns its keep three ways. It blocks rain and snowmelt from pouring straight down the flue, it screens out birds, squirrels, and raccoons looking for a warm nest, and its spark arrestor keeps burning embers from landing on your roof. In short, it protects both the chimney and the house around it.
Signs your Lake in the Hills chimney cap needs attention
You can spot many cap problems from the ground with a quick look, especially after a rough winter or a storm. Watch for these:
- Rust streaks running down the exterior masonry.
- A cap that looks crooked, dented, or partly torn away.
- Animal noises, nesting material, or a musty smell from the fireplace.
- Water in the firebox or a damp, moldy odor after rain.
- Bits of mesh or metal showing up in the firebox.
What happens without a cap
An uncapped flue lets every rainfall soak the liner, the damper, and the surrounding masonry, and that moisture is the leading cause of chimney deterioration in our freeze-thaw climate. Left alone it rusts the damper, cracks the liner, and eventually forces a relining or masonry repair that costs far more than the cap ever would. Animals nesting in an open flue are both a fire hazard and a blockage that can push carbon monoxide back into the home.
Choosing the right cap
Caps come in galvanized steel, stainless steel, and copper, and the right choice depends on your flue size and how long you want it to last. Stainless steel is our usual recommendation for Lake in the Hills homes because it resists rust through years of Illinois weather. What matters most is a correct fit and a solid installation — a cap that blows off in the first windstorm protects nothing. We measure and fit each one to the flue.
Book a cap check in Lake in the Hills
Ace Chimney Service is based in nearby Crystal Lake and serves Lake in the Hills seven days a week, 7 AM to 7 PM. A cap check is part of every chimney cap and crown visit, and we give you the price up front — you can review our rates on the pricing page. Call (815) 320-0883 to get on the schedule. We are insured and bonded.
Frequently asked questions
How much does a chimney cap cost to install?
It depends on the cap material and your flue size. We give you the price up front before any work begins, and our current starting rates are listed on our pricing page.
Can I install a chimney cap myself?
We do not recommend it. Rooftop work is dangerous, and a cap that is the wrong size or poorly secured can blow off or fail to seal, leaving the flue exposed. A correct fit is what makes a cap effective.
How long does a stainless steel chimney cap last?
A quality stainless steel cap, properly installed, commonly lasts many years through Illinois weather. We check its condition at every annual inspection so you catch wear before it becomes a leak.
Will a cap stop downdrafts and smoke smells?
A cap helps with rain-driven odors and keeps debris out, but persistent downdrafts or smoke smells can also point to draft or liner issues. An inspection tells us the real cause.
Do chimney caps keep animals out?
Yes. The screen on a properly fitted cap keeps birds, squirrels, and raccoons from nesting in the flue, which is both a blockage risk and a fire hazard.
My cap is rusted — can it be repaired or must it be replaced?
A lightly weathered cap can sometimes be cleaned and resecured, but a rusted-through or bent cap should be replaced so it seals correctly. We advise the more cost-effective option after looking at it.
Does a chimney cap help prevent chimney fires?
The spark arrestor screen keeps burning embers from escaping onto the roof, which reduces one fire risk. Regular sweeping to control creosote is the other key step.
Do you serve Lake in the Hills and nearby towns?
Yes. We are based in Crystal Lake and serve Lake in the Hills, Algonquin, Cary, and the wider McHenry County area seven days a week.
Published August 9, 2026