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.
Olympia Chimney Chimney Cap Installation: The Chelmsford Owner’s Guide
Olympia Chimney chimney cap installation in Chelmsford typically runs $340-$680 depending on flue size and whether your crown needs repair before the cap goes on. We stock Olympia Chimney-compatible caps in common sizes for Chelmsford’s pre-1980s colonials and split-levels, and most replacements are completed in a single visit. Call us at (978) 991-9492 for a free estimate with upfront pricing.
Most Chelmsford homeowners figure out their chimney cap is done when they spot rust streaks down the brick or hear water dripping during a March nor’easter. Sometimes it’s a neighbor who notices the cap tilted after a windstorm off Heart Pond. Either way, a failed cap quits protecting your flue from rain, animals, and the freeze-thaw cycles that chew up Massachusetts masonry.
Which Olympia Chimney Models This Applies To
Olympia Chimney manufactures caps for their own liner systems and for universal fit over terra-cotta flue tiles. The critical match is your flue’s outside dimension, not the brand name on your fireplace manual. Olympia’s stainless caps come in standard sizes: 8″×8″, 8″×13″, 13″×13″, and the less common 13″×18″ you’ll find on some of the larger Center Chimney colonials near the Common.
To identify yours, measure the outside of your flue tile at the crown, not the inside opening. Check for a stamped model number on any remaining cap hardware. Olympia’s 304-grade stainless caps carry a part prefix of “OLY-” followed by the dimension code. We also fit quality aftermarket equivalents from Gelco and Famco when the OEM lead time stretches past burning season. Hearthstone Chimney Co. is an independent service provider, not affiliated with Olympia Chimney, so we source what fits your flue correctly rather than pushing a particular badge.
One Chelmsford-specific gotcha: homes in the historic district with modified flues from the 1970s oil-to-gas conversions sometimes have oddball 9″×9″ tiles that sit between standard sizes. We carry adapter skirts for these, but they require field measurement.
Signs Your Olympia Chimney Chimney Cap Installation Is Failing
- Rust stains on the brickwork below the crown. Olympia’s stainless caps resist corrosion, but the spot-welded seams on pre-2010 units can weep once the passivation layer wears thin. Chelmsford’s road salt aerosol from winter plowing accelerates this at the cap’s leading edge.
- Water in the firebox after heavy rain. A cap with a damaged or missing lid lets water track down the flue. In older Chelmsford homes with exterior chimneys, that water hits the smoke shelf and can wick into surrounding framing.
- Squirrel or bird noise in the flue. Mesh sides on an Olympia cap keep animals out, but the 5/8″ wire can get bent by falling branches or ice load. Once the mesh gaps, starlings nest fast, usually in April.
- Cap sitting crooked or shifted from wind. The clamp-band system on single-flue Olympia caps loosens over years of thermal cycling. We’ve found caps tilted 15 degrees after the 2018 windstorms that came through Middlesex County.
- Draft problems or smoky fireplace. A cap with a clogged or undersized lid can restrict exhaust flow. This shows up first on cold, damp Chelmsford mornings when the air column in the flue is heavy and reluctant to rise.
Replacement Cost & What’s Included
| Scope | Price Range |
|---|---|
| Olympia Chimney cap replacement, standard flue, no crown work | $340-$480 |
| Cap plus minor crown sealing (cracks under 1/4″) | $480-$580 |
| Cap with crown rebuild or extensive flashing | $580-$680+ |
| Odd-size flue requiring custom adapter | Add $80-$140 |
What drives the range: flue accessibility (steep roof pitch adds time), whether the existing cap left corrosion damage to the flue tile top, and if the crown needs attention before a new cap seals properly. We price everything upfront before starting. The number on the estimate is the number on the invoice. Every cap installation includes our 90-Day Done Right Promise in writing, no arguing. If it leaks or shifts, we come back.
DIY or Call Us?
There’s a safe middle ground here. You can check your flue size with a tape measure from the roof edge if you’re comfortable on a ladder, and you can spot obvious damage from the ground with binoculars. What you shouldn’t do is attempt the actual installation yourself.
Chimney cap work means working at roofline height on a surface that may be slick with moss or frost, often near the edge. The clamp-band systems require two hands and proper torque; an under-tightened band launches the cap in the next windstorm, and an over-tightened one cracks the flue tile. We’ve been called to retrieve DIY caps from gutters, shrubs, and once a neighbor’s yard on Richardson Road. If the flue isn’t right, the fire isn’t safe - it’s that simple. Call (978) 991-9492 and we’ll handle the roof work.
FAQs
A properly installed 304-grade stainless Olympia cap lasts 15-20 years in Chelmsford’s climate, though road salt exposure and ice dam runoff can shorten that to 10-12 years on chimneys within 200 feet of heavily salted roads. Call (978) 991-9492 for a free estimate - estimates are free.
Spot-welded seam leaks and minor mesh damage can sometimes be patched, but if the lid is warped or the clamp band is corroded, replacement is the sounder choice. We show you the condition on camera before deciding. Call (978) 991-9492 for a free estimate - estimates are free.
Most Olympia Chimney cap replacements take 45-90 minutes from ladder set to cleanup, assuming no crown repair is needed. We carry common sizes on the truck and complete most jobs in a single visit. Call (978) 991-9492 for a free estimate - estimates are free.
We stock stainless caps that fit Olympia Chimney systems in the four standard flue sizes, plus adapter hardware for odd sizes common in older Chelmsford homes. If your cap requires a special order, we’ll tell you before booking. Call (978) 991-9492 for a free estimate - estimates are free.
Ready to get this handled before the next storm? Call Hearthstone Chimney Co. at (978) 991-9492. A live person answers 24 hours a day, 7 days a week - not a voicemail, not a callback queue. We’ll schedule your free estimate, show you photos of what we find, and give you a plain-English verdict with no-hassle upfront pricing. We’ve been serving Chelmsford and nearby communities for over 42 years, and we plan to be here when your next cap needs attention.
Written by Russell Haines, Owner, Hearthstone Chimney Co. at Hearthstone Chimney Co., serving Chelmsford and nearby areas.





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