Level 1 sweep and inspection to the NFPA 211 annual standard - flue, crown, cap, and flashing checked and photographed
Chimney sweep logs do not sweep chimneys. They loosen some creosote - which then falls where a brush and vacuum still have to collect it.
Famco Chimney Cap Installation: The Gaithersburg Owner’s Guide
We stock and install Famco-compatible chimney caps across Gaithersburg, with most replacements running $280 to $550 installed depending on flue size and whether your crown needs resealing. If you call us in the morning, we can usually inspect and quote same-day, and many jobs finish in a single visit. Most Gaithersburg homeowners discover the cap has failed when water spots appear on the ceiling near the fireplace or when a neighbor mentions rust stains running down their brick - by then, moisture has already been getting in for a season or two.
Which Famco Models This Applies To
Famco builds chimney caps in galvanized, stainless, and copper across several series lines. The most common we see in Gaithersburg are the standard single-flue galvanized caps in 8″×13″ and 13″×13″ base dimensions, plus the multi-flue models that cover the full crown on older colonials with multiple fireplaces. To identify yours, check the stamped model number on the underside lip of the cap - it’s usually visible from the roof edge with a pair of binoculars. If the stamp has weathered off, measure the flue tile opening (not the cap itself) and note whether you have a clay flue tile, a metal flue, or a factory-built chimney.
We carry both OEM Famco caps and stainless aftermarket equivalents from Gelco and Olympia Chimney on our trucks. The aftermarket units match Famco dimensions exactly and often outlast the original galvanized caps in Montgomery County’s freeze-thaw cycles. If your cap is under ten years old and already rusting through, you’re not alone - we’ve replaced dozens of original-equipment galvanized caps in the Kentlands area that simply weren’t spec’d for Maryland humidity.
Signs Your Famco Chimney Cap Installation Is Failing
- Water stains on the ceiling near the chimney breast. A cracked or dislodged Famco cap lets rain run straight down the flue. In Gaithersburg’s spring storms, a single missing corner of a cap can funnel gallons into the smoke chamber over a season.
- Rust streaks down the brick or siding below the chimney. Galvanized Famco caps start bleeding rust at the seams after 7-12 years in our climate. The streaks are cosmetic early on, but they signal the metal is thinning and will soon perforate.
- Birds or squirrels in the flue. Famco caps with missing or damaged mesh screens are an open invitation. We’ve pulled nests from flues in the Lakelands neighborhood where a $40 screen repair was ignored until the smell forced the call.
- The cap is visibly tilted or lifted on one side. Wind gusts common to the I-270 corridor can loosen poorly secured caps. A tilted cap channels water in rather than shedding it, and the gap underneath is exactly how raccoons access chimneys.
- Draft problems or smoky fireplace even with the damper open. A Famco cap with clogged mesh or one that’s been dented inward can restrict airflow. We’ve seen caps crushed by falling ice from higher rooflines - the damage isn’t always visible from the ground.
Replacement Cost & What’s Included
| Service | Typical Range in Gaithersburg |
|---|---|
| Single-flue Famco cap replacement (galvanized) | $280 - $380 |
| Single-flue Famco cap replacement (stainless) | $340 - $450 |
| Multi-flue crown-cover cap (stainless) | $420 - $550 |
| Crown resealing with HeatShield (if needed) | $180 - $280 additional |
| Flue tile repair or mortar wash | $150 - $320 additional |
What drives the range: flue height above the crown (taller requires longer legs), whether the existing fasteners are seized or broken out, and crown condition. We inspect with a camera before quoting - you’ll see the photos, and we’ll tell you plainly if the crown work can wait or if it needs addressing now. Every cap installation carries our 90-Day Done Right Promise in writing. The price we quote is the price on the invoice.
DIY or Call Us?
There’s no spring tension or electrical hazard in a chimney cap swap, but there is a roof, and in Gaithersburg many of our chimney caps sit on two-story colonials with 8/12 pitches or steeper. A homeowner can safely check from the ground with binoculars for visible tilt, rust, or missing mesh. You can also verify water stains inside by looking at the ceiling directly below the chimney breast after a hard rain.
Where DIY goes wrong: walking a steep composite or slate roof without proper fall protection, stripping the fasteners in soft crown mortar and making the leak worse, or installing a cap with the wrong leg height that traps creosote against the flue. We’ve been called to fix homeowner installations where the cap was right-side-up but the mesh was on the outside, or where silicone was used instead of proper masonry fasteners and the first wind took it to the neighbor’s yard. If it’s worth heating your home with, it’s worth doing the maintenance correctly. Call us at (301) 719-5236 and we’ll handle the roof work.
FAQs
Galvanized Famco caps typically last 8 to 14 years in Montgomery County’s climate before rust-through, while stainless and copper versions often exceed 20 years. The difference is real - we’ve replaced galvanized caps in the Kentlands that failed in seven years while neighboring stainless caps from the same installation batch are still solid. Call (301) 719-5236 if you’re unsure which material you have; we can tell from the ground most days.
Mesh screens can be patched or reattached if the frame is sound, but once the galvanized steel body shows pinholes or seam separation, replacement is the only lasting fix. Rust is like rot in wood - by the time you see it, the metal around it is compromised. We’ll show you the camera footage so you can decide for yourself whether a repair buys real time or just delays the inevitable.
Most Famco cap replacements take 45 minutes to 90 minutes on site, assuming standard access and no crown repair. We carry the common sizes on the truck, so there’s no ordering delay. You’ll get photos before and after, plus a written invoice with our 90-Day Done Right Promise.
We stock Famco-compatible caps in galvanized, stainless, and copper on our service trucks, along with equivalents from Gelco and Olympia Chimney. You don’t need to source anything - we measure, match, and install. If you have an unusual size or a custom copper job, we can fabricate to spec with a short lead time. Hearthstone Chimney Co. is an independent service provider and not affiliated with Famco.
Written by Russell Haines, Owner, Hearthstone Chimney Co. at Hearthstone Chimney Co., serving Gaithersburg and nearby areas.





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