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 Manassas Owner’s Guide
We install Famco chimney caps across Manassas for $280-$520 depending on flue size and whether your crown needs repair before mounting. Most replacements are completed in a single visit, and we stock the common Famco galvanized and stainless-steel sizes on our trucks. Homeowners usually discover the problem during a heavy rain, when water stains appear on the firebox wall, or when the cap itself is sitting crooked after a windstorm off the Bull Run hills.
Which Famco Models This Applies To
Famco produces chimney caps in three main material grades: galvanized steel (series starting with G-), 304 stainless steel (S-), and 316 stainless steel (M- for marine-grade). The model number is stamped on the underside of the lid or on a small tag at the mesh corner. In Manassas, we most often replace the G-12 and S-12 series on 1980s and 1990s brick colonials, and the larger S-14 and M-14 on homes with multiple flues near the battlefield district.
The critical measurement is your flue’s outside dimension, not the cap’s overall width. A 13×13 flue needs a cap with a minimum 15-inch skirt to overhang properly. We see mismatched caps every season in Prince William County, usually from a homeowner who bought by roofline eyeball rather than flue tape measure. Aftermarket caps from Gelco or Olympia Chimney will fit Famco mounting brackets if the flue size matches, but the bolt pattern differs on older Famco units pre-2010. We carry adapters for that transition. Hearthstone Chimney Co. is an independent service provider with no affiliation to Famco.
Signs Your Famco Chimney Cap Is Failing
- Rust streaks running down the chimney face. Galvanized Famco caps in Manassas typically show surface rust at year 7-9, faster if you’re within two miles of I-66 where road salt spray accelerates corrosion. Once rust reaches the skirt seam, the cap is channeling water directly onto your crown.
- Mesh sides pulled away from the frame or clogged solid with creosote. Famco’s 5/8-inch spark arrestor mesh is tight enough to catch debris but can cake shut in fireplaces burned daily from November through March. A clogged mesh reverses your draft and pushes smoke into the room.
- The cap tilts or rotates after wind. The Bull Run gap funnels northwest winds that test any mounting system. Famco’s older screw-tension brackets fatigue after a decade; we replace these with stainless steel tapcon anchors into the crown itself.
- Water in the firebox or white efflorescence on exterior brick. This means the cap is either missing its lid overhang, the lid seam has separated, or the flue is un-capped entirely. In Manassas’s freeze-thaw cycle, one season of direct water entry starts crown cracks that cost far more than the cap.
- Animal noise or nesting debris. Squirrels compress Famco mesh to squeeze through; raccoons simply pull lightweight galvanized caps loose. We find nests most often in homes backing to wooded lots near Manassas National Battlefield Park.
Replacement Cost & What’s Included
| Service | Price Range |
|---|---|
| Famco cap removal and disposal | $85-$120 |
| Galvanized replacement cap (G-series) | $140-$190 |
| 304 stainless replacement cap (S-series) | $220-$310 |
| 316 marine stainless (M-series) | $290-$380 |
| Crown repair before mounting (if needed) | $180-$340 |
| Stainless tapcon anchor upgrade | $45-$65 |
Your total installed price lands in that $280-$520 window for most Manassas homes. Crown repair pushes the high side; a straightforward swap on sound masonry sits at the low end. We photograph the crown condition before quoting, so you see what we see. The price we agree to is the price on the invoice. Our 90-Day Done Right Promise covers the installation and hardware; Famco’s material warranty runs 10 years on stainless, 3 years on galvanized.
DIY or Call Us?
A homeowner can safely check whether the cap rocks by hand, whether mesh is clogged, and whether rust has reached the skirt seam. Use binoculars from ground level; do not climb the roof. The actual replacement involves working at height with proper fall protection, cutting old fasteners that may shear off, and sealing the new mounting without voiding the material warranty through improper torque or incompatible sealant. We’ve rescued more than one DIY attempt in Manassas where the cap blew off the next storm because the crown was crumbly underneath and nobody checked. If the flue is clear and the mortar is solid, we’ll tell you that. If it isn’t, we’ll tell you that too. For an honest assessment, call (571) 586-0593.
FAQs
Galvanized caps last 7-10 years here, stainless steel 15-25 years, with 316 marine-grade pushing past 20 even with our freeze-thaw winters and summer humidity spikes. Call (571) 586-0593 and we’ll check what you have now.
Mesh can be cleaned and minor rust spot-treated, but once the skirt seam opens or the lid deforms, replacement is the sound repair. We don’t patch caps because the labor equals a new unit and the result doesn’t last. Call for a free look.
Most Famco replacements take 45-90 minutes on site, longer if crown repair is needed. We complete most jobs in a single visit because we stock common sizes. Call (571) 586-0593 to confirm your size is on the truck.
We stock galvanized and 304 stainless Famco-compatible caps in the sizes that fit 80 percent of Manassas homes, plus Gelco and Olympia Chimney equivalents for same-day completion. Uncommon sizes are next-day from our Fairfax supplier. Call to confirm your fit.
Written by Russell Haines, Owner, Hearthstone Chimney Co. at Hearthstone Chimney Co., serving Manassas and nearby areas.





Before
After
Before
After
Before
After