The short answer
A chimney cap or chase cover keeps water, animals and debris out of your chimney while letting exhaust out. If you see water in the firebox, hear animals, or notice white staining or rust streaks on the chimney, the top is likely missing or failing. Have it inspected and fitted with a properly sized cap or cover.
The top of your chimney takes more weather than almost any other part of the house. A chimney cap keeps rain, snow, birds, squirrels and leaves out of the flue while letting smoke and exhaust escape. A chase cover is the metal top that seals a chimney chase, the framed, boxed enclosure built around a factory-made fireplace flue. When a cap or chase cover is missing, rusted, cracked or the wrong size, water and animals find their way in. The damage usually shows up inside the house before anyone looks at the roof. Apex Premier Chimney Services measures, installs and replaces chimney caps and chase covers for homes in New York and nearby cities. While we're up there, we also check the rest of the chimney top.
Signs you need it
Most cap and chase cover problems are noticed from inside the house. Look and listen for these:
One of these signs doesn't always mean the cap is the only problem. Water can also get in through cracked mortar or a damaged crown, so we look at the whole chimney top before recommending a fix.
- Water in the firebox, damp ashes, or drips on the damper after rain or snowmelt
- Animal noises in the chimney, such as scratching, chirping or flapping, especially in spring
- Debris in the firebox: leaves, twigs, nesting material, or flakes of brick and mortar
- White staining on the brick, a chalky residue left when water moves through masonry
- Rust streaks running down the siding below a metal chase cover
- Poor draft or smoke rolling into the room, which can happen when a nest blocks the flue or wind pushes down an open chimney
- A musty or creosote smell that gets stronger in humid or rainy weather
What's included
Every cap or chase cover visit follows the same checklist. That holds whether we're adding a cap for the first time or replacing a rusted chase cover.
- Measure each flue or chase top so the new cap or cover fits the actual opening
- Inspect the crown, mortar joints and flashing at the chimney top for cracks or gaps
- Check the flue opening for nests, leaves and blockages, and clear what we can reach
- Remove the old cap or chase cover along with any loose fasteners or failed sealant
- Install a cap with mesh screening sized to keep out birds and animals while allowing draft
- For chase covers, fit a cover with a sloped top and drip edge so water sheds away from the chase
- Fasten and seal the cap or cover so it stays in place in high wind
- Take before-and-after photos of the chimney top so you can see what we saw
- Give you a written note of any other problems we find, such as crown cracks or a damaged liner
How our crew works in your home and on the roof
Inside, the crew lays drop cloths from your door to the fireplace and around the hearth before touching anything. Sometimes nesting material or debris has fallen into the smoke chamber. We clear it with rotary brushes and pull it out with HEPA vacuums, which keeps soot and dust out of the room. If we're unsure whether there's damage farther down the flue, we run a camera to check the liner without opening walls.
On the roof, our certified technicians set up ladders and roof protection to reach the chimney safely. That applies to a pitched roof on a single-family house and to a flat roof on a rowhouse. If an animal is still nesting inside, we confirm it has left before closing off the flue. A cap installed over a live nest traps the animal inside, and the problem stays with you. We clean up the roof and work area before we leave.
The standard we follow
The NFPA 211 standard calls for chimneys, fireplaces and vents to be inspected once a year. A cap or chase cover job is a practical time to do that inspection, since we're already at the top of the chimney.
Chimney professionals use three inspection levels: - Level 1 fits when nothing about the system has changed. - Level 2 is called for when the system changes, such as a new appliance or a switch of fuel, or when the home is sold. - Level 3 applies when a hidden hazard has to be reached by opening part of the chimney or building. Most cap and chase cover visits pair with a Level 1 inspection. We'll tell you if what we find points to a higher level.
Some New York City buildings convert their boiler from oil to gas. When that happens, the chimney has to be evaluated as part of the work. A new liner is often needed, because gas exhaust produces acidic condensate that can corrode a masonry flue. The cap should then be chosen to fit the new liner.
What affects the price
We give you a quote after we've seen the chimney. The main factors are:
- Chimney height and roof access, including roof pitch and building height
- The fuel the flue serves (wood, gas or oil), which affects cap material and design
- Flue size, the number of flues, and the condition of the flue tiles and crown
- How much debris, nesting material or buildup has to be cleared
- Whether a standard size fits or a custom cap or chase cover is needed
- Whether a camera inspection or a repair, such as crown or mortar work, is needed
How a visit works
First, you tell us what you've noticed, such as water in the firebox or noises in the chimney, and we schedule a visit. On site, we look at the fireplace from inside, then go up to the roof to measure and inspect the chimney top. We show you photos, explain what we found, and give you options before any work starts.
Some caps can be installed the same day. Custom chase covers and multi-flue caps are made to measure, so we come back to install them once they're ready.
If you own a building with tenants, plan around New York City's heat season. It runs from October 1 through May 31, and owners must keep apartments heated to the city's minimum temperatures during that time. Scheduling chimney top work before fall helps you avoid interruptions.