Marlborough, MA · Middlesex County

Chimney Screen Installation in Marlborough, MA

Humane removal of birds, squirrels, raccoons, bats, and nesting debris from your chimney, followed by a full flue cleanout and exclusion work so wildlife never moves back in. Most animal and nest removals in the Boston area run a typical range of $249–$595 depending on the species involved, how deep the nesting material sits in the flue, and whether a full cleanout and sanitizing are needed afterward.

Call (781) 653-5644

A surprising number of people searching for "chimney screen installation" are not reacting to a symptom at all — they are reacting to paperwork. A home inspector flagged something during a sale. An insurance carrier asked questions after a claim. An appraiser noted the chimney's condition. Chimneys sit at an awkward intersection of safety, structure, and liability, which is why they show up in so many transactions. Whether your search started with paperwork or with an actual problem, the underlying questions are the same: what is wrong, how serious is it, and what does a proper fix involve? Upside Down Chimney Sweeps answers all three below, drawing on the standards — NFPA 211 inspections in particular — that inspectors and insurers rely on. For documentation you can actually hand to a third party, call (781) 653-5644.

Chimneys hide their problems better than almost any other part of a house. The flue interior is invisible without a camera. The crown is above the roofline where nobody looks. Flashing failures leak into wall cavities and show up as mysterious stains rooms away from the chimney. Even serious creosote accumulation is out of sight the moment you step back from the firebox. This is why homeowners are so often blindsided — not because they were careless, but because the evidence was structurally concealed. It is also why the chimney trade leans so heavily on scheduled inspections rather than wait-for-symptoms maintenance. By the time a chimney problem is visible from the living room, it has usually been developing for years. The search that brought you here may be the first visible edge of something older.

The stakes with chimney problems are not hypothetical. A chimney's core function is containment: keeping flue gases, sparks, and extreme heat inside a sealed passage until they exit above the roof. Carbon monoxide is odorless and colorless, and a blocked or leaking flue can push it back into living space instead of venting it outside. Meanwhile, creosote — the tar-like residue wood smoke deposits inside the flue — is fuel waiting for an ignition source, and chimney fires often burn unnoticed until they have damaged the liner or spread toward framing. This is why both NFPA 211 and CSIA guidance treat annual inspection as a baseline, not an upsell. Most chimney issues are discovered during a routine visit, long before they become emergencies. The dangerous ones are almost always the ones nobody was looking at.

Animal & Nest Removal in Marlborough, MA

Please do not try to smoke an animal out. It is the single most dangerous piece of folk advice in this trade. Lighting a fire under a nest of dried twigs ignites a flue blockage directly above your firebox, and lighting one under a trapped animal usually kills it where it sits, leaving you with a carcass wedged above the damper and an odor problem that lasts weeks. Squirrels are a special case: glazed clay flue tiles offer their claws no grip, so a squirrel that falls past the smoke shelf physically cannot climb back out. It is not visiting your chimney at that point; it is trapped, dehydrating, and desperate, and it needs to be lifted out by someone with the right equipment.

That scratching, chirping, or frantic fluttering coming from behind your fireplace wall is one of the most common calls we take every spring and early summer. A chimney mimics the hollow tree that raccoons, squirrels, chimney swifts, and bats have denned in for thousands of years: tall, dark, sheltered from hawks and weather, and gently warmed by the house below. An uncapped flue in Marlborough is an open invitation, and once an animal moves in you are dealing with far more than noise. Nesting material chokes the flue, droppings carry real pathogens, and a mother raccoon guarding kits on the smoke shelf will defend that ledge aggressively. We remove the animals humanely, clear every trace of the nest, and seal the chimney so it never happens again.

Knowing what species you are dealing with changes everything about how the job must be done. Chimney swifts, the small cigar-shaped birds that glue half-cup twig nests to flue walls, are protected under the federal Migratory Bird Treaty Act, so an active nest with eggs or young cannot legally be removed; we document it, protect your home in the meantime, and schedule the cleanout and capping for the day the brood fledges. Bats carry their own protections in Massachusetts and can only be excluded outside of maternity season. Raccoons and gray squirrels, on the other hand, can be removed promptly, but the method matters: separate a mother from her litter carelessly and she will tear through flashing, shingles, and even ridge vents to get back to them.

What the Service Includes

1Humane Wildlife Removal

We identify the species first, because the removal method depends on it. Trapped squirrels are lifted out with padded retrieval poles or a weighted escape rope they can climb. Raccoons are removed with the litter kept together, so the mother relocates her kits instead of ripping her way back into your roofline. Birds resting above the damper are guided up and out rather than into your living room. Every removal is done from the top of the flue and the firebox simultaneously, so the animal has one calm exit path.

2Complete Nest & Debris Cleanout

A nest is never just a nest. Raccoons haul in armfuls of leaves and bark; squirrels pack the smoke shelf with insulation stolen from your own attic; swifts leave twig cups cemented to the tile with saliva. We remove every scrap with brushes, rods, and a HEPA-filtered vacuum, then scan the full flue with a camera to confirm nothing remains lodged at an offset or above the smoke chamber. Organic debris left behind is kindling sitting directly in the path of your exhaust, so partial cleanouts are not something we do.

3Protected Species Compliance

Chimney swifts are federally protected under the Migratory Bird Treaty Act, and several Massachusetts bat species have additional state protections, so timing is part of the job. When we find an active swift nest, we confirm the stage of the brood, give you a realistic fledge date, and return to clean and cap on schedule. Bat exclusions are planned around maternity season, using one-way exclusion devices rather than trapping. You stay legal, the wildlife stays alive, and your chimney still ends up sealed before the burning season.

4Sanitizing & Deodorizing

Animal occupation leaves biological residue that has no business above your firebox. Accumulated bird and bat droppings can host the fungus that causes histoplasmosis, raccoon latrines can carry roundworm, and abandoned nests shed mites and fleas that migrate into the house once their host is gone. After the physical cleanout we treat the smoke shelf, smoke chamber, and firebox with an atomized disinfectant and deodorizer formulated for chimney use. That step is also what breaks down the den scent that would otherwise advertise your flue to the next animal.

5Dead Animal Location & Removal

A sudden fly problem at the fireplace or a sweet, heavy odor that worsens on warm days usually means an animal died above the damper. Carcasses rarely sit where you can see them; they wedge on the smoke shelf, at flue offsets, or behind the damper plate. We locate the remains with an inspection camera, remove them through the firebox or from the top of the flue, and follow with the full sanitizing treatment. In Marlborough homes with older throat dampers, we also check that decomposition fluids have not corroded the damper seat.

6Exclusion & Chimney Cap Installation

Removal without exclusion is a subscription, not a solution, because a scent-marked den draws new tenants every season. We close the entry permanently with a stainless steel cap sized to your flue, with mesh tight enough to stop bats and swifts but open enough to preserve draft, per NFPA 211 termination requirements. Multi-flue chimneys get a full-coverage cap; open masonry flues serving oil or gas appliances get screened terminations that will not clog with frost. We also point out roofline gaps and flashing lifts that give animals their approach route.

How We Diagnose and Fix It

When the problem involves a wood-burning flue, diagnosis includes assessing creosote, which the trade grades in three stages. Stage 1 is light, sooty, and brushes out easily — the normal product of good burning habits. Stage 2 is harder, flakier, and shinier, requiring more aggressive tools. Stage 3 is the serious one: a glazed, tar-like coating that has hardened onto the flue, cannot be removed with brushes alone, and is highly flammable — the primary fuel in chimney fires. The stage determines both the removal method and the urgency. A sweep will also read what the creosote says about cause: heavy glaze often points to smoldering fires, unseasoned wood, or a flue that is oversized or running too cool for its appliance. Cleaning without correcting the cause just schedules the next buildup.

Masonry repairs succeed or fail on materials and prep, not just workmanship. Repointing — cutting out failed mortar joints and refilling them — only lasts when the new mortar matches the old in hardness; modern Portland-heavy mixes are actually too strong for older Massachusetts brick and cause the surrounding faces to spall. Crown work has its own rules: a proper crown is cast concrete with an overhang and drip edge, not a thin mortar wash troweled over the top course, and a badly failed crown gets rebuilt rather than endlessly patched. Spalled bricks are cut out and replaced individually where damage is contained. When animal removal is on the table, ask the contractor what mortar type they intend to use and why — the answer tells you quickly whether you are dealing with a chimney specialist or a generalist.

Warning Signs to Watch For

You hear scratching, scurrying, or thumping inside the chimney, especially around dawn and dusk.
High-pitched chirping or raspy chattering from the flue that gets louder when a parent animal returns to feed young.
A musky, ammonia-like, or decaying odor drifts from the fireplace and gets worse on humid days.
Twigs, leaves, grass, or tufts of insulation are poking through the damper or dropping into the firebox.
Flies keep gathering at the fireplace glass or hearth, which often signals a dead animal above the damper.
A fireplace that drafted fine last season suddenly pushes smoke back into the room.
You find droppings, feathers, or shredded nesting material on the smoke shelf or hearth.
Your chimney cap is missing, visibly damaged, or was never installed in the first place.
You keep seeing squirrels or a raccoon on the roofline near the flue, particularly in early morning.
You hear frantic, repetitive scrambling that never progresses upward, the classic sound of a squirrel trapped on slick flue tile.

Why This Matters in Marlborough

Marlborough's housing stock spans its shoe-factory era through its tech-corridor present: Victorian and early-1900s homes with original brick chimneys ring the downtown, while postwar capes and split-levels fill the neighborhoods off Route 20. Large condo and apartment complexes built from the 1980s onward add shared metal-flue and prefab fireplace systems to the mix.

As a former mill city turned I-495 commercial hub, Marlborough has an unusually wide spread of chimney ages, from 1880s downtown masonry to builder-grade prefab units in newer subdivisions. The city's elevation along the Assabet watershed brings hard freeze-thaw cycles that work open mortar joints on older stacks.

Greater Boston weather asks masonry to survive genuine extremes. A chimney in Marlborough may face humid ninety-degree afternoons in July and single-digit nights in January, along with the dozens of freeze-thaw crossings in between that make southern New England one of the tougher masonry climates anywhere. Materials expand and contract with every swing, mortar fatigues, sealants age, and metal components like caps, dampers, and flashing corrode faster in our damp air. None of this means chimneys here are doomed; it means maintenance schedules imported from gentler climates simply do not apply. An annual inspection is the standard everywhere under NFPA 211, but around here it earns its keep almost every single year, usually by catching weather damage early.

What It Typically Costs

Chimney repair pricing varies more than sweep pricing because chimneys fail in such different ways and places. The main drivers are extent, access, and materials. Repointing a few mortar joints is a different undertaking from rebuilding a chimney from the roofline up. Work high on a steep roof may require staging that a walk-up ranch never would. And in the older neighborhoods we serve, matching brick and mortar appropriately matters, both for appearance and because modern mortar that is harder than antique brick can actually accelerate damage to the original masonry. A written estimate after an actual inspection is the only number worth trusting, and it should itemize the work plainly enough to compare against any other bid.

Why Call Upside Down Chimney Sweeps

Plenty of companies will run a brush through your flue. What sets Upside Down Chimney Sweeps apart is everything that happens around the brush. We document our inspections with photographs, so you see exactly what we see inside your smoke chamber and up your flue. We explain findings against the actual language of NFPA 211 rather than vague warnings. We give written estimates before repair work begins, not after. And because we are a local outfit based in Melrose rather than a franchise dispatching strangers, the technician in your driveway has a personal stake in doing the job right. Our business grows on referrals between neighbors, which is exactly the kind of pressure a homeowner should want a contractor to feel.

Frequently Asked Questions

What kind of animal is most likely in my chimney?

In Eastern Massachusetts the usual suspects are gray squirrels, raccoons, chimney swifts, and occasionally bats or a stray bird from an open heating flue. The sounds narrow it down fast. Frantic scrambling that never gets anywhere is almost always a squirrel trapped on slick flue tile. Slow, heavy movement and low chittering, mostly at night, points to a raccoon, and if it arrived in spring she likely has kits on the smoke shelf. A rhythmic chorus of raspy chirps that erupts every few minutes is a swift nest with hungry young. Tell us what you are hearing when you call and we will usually know what we are walking into before we arrive.

The birds in my chimney are chimney swifts. Can you remove them?

Not while the nest is active, and neither can anyone else legally. Chimney swifts are protected under the federal Migratory Bird Treaty Act, which prohibits disturbing an active nest with eggs or dependent young. The good news is that swifts are on a short clock: the young typically fledge within several weeks, the noise peaks just before they leave, and the whole family departs for the season. We confirm the nest stage, protect your home in the meantime by sealing the damper so nothing ends up in your living room, and then return to remove the nest debris, sweep and sanitize the flue, and install a cap before the next nesting season.

Can I just light a fire and drive the animal out?

Please do not. If the flue is blocked by a nest, you are igniting dry tinder inside your own exhaust system, and a nest fire can crack flue tiles and extend into the structure. If the animal is trapped, which is the case for virtually every squirrel in a lined flue, it cannot climb out no matter how motivated it is, so the fire kills it above your damper and you trade a noise problem for weeks of odor, flies, and a carcass extraction. Smoke also does nothing to a raccoon on the smoke shelf except make her dig deeper. Call (781) 653-5644 instead; humane removal is usually faster than people expect.

How much does animal removal from a chimney cost?

Most jobs in the Marlborough area land in a typical range of $249–$595, and where you fall in that range depends on a few concrete factors: the species and number of animals, how deep the nesting material extends into the flue, whether a dead animal recovery and sanitizing treatment are needed, and the condition of the flue once it is clear. A trapped squirrel lifted out of an otherwise clean chimney sits at the low end; a multi-year raccoon den packed above an offset with a full cleanout and deodorizing sits at the top. We give you a firm price after the camera look and before any work begins, so there are no surprises.

What do you do about bats in a chimney?

Bats get handled differently from everything else because Massachusetts protects them and because several local species, especially little brown bats, have been devastated by white-nose syndrome. We never trap or handle bats out of a flue. Instead we install one-way exclusion devices that let the colony exit to feed at night but not re-enter, and we only do that outside the summer maternity window, when flightless pups would otherwise be sealed inside. Once the colony is out, we clean and sanitize the flue, since accumulated guano can harbor the histoplasmosis fungus, and we cap and screen every opening so the roost is closed permanently.

How do you keep animals from coming back after removal?

Exclusion is the half of the job that actually solves the problem. An animal den is scent-marked, and that scent advertises a proven nursery site to every raccoon and squirrel that crosses your roof, which is why chimneys that get cleaned but not capped are reoccupied within a season or two. We sanitize to break down the scent, then install a stainless steel cap with welded animal-proof mesh, mechanically fastened so a raccoon cannot pry it off the flue tile. We also walk the roofline and point out flashing gaps, rotted fascia, and open ridge vents, because a determined animal denied the flue will look for the next opening.

I think the animal in my chimney is dead. Now what?

The telltale signs are a heavy, sweet odor that intensifies on warm or humid days, flies gathering at the fireplace, and the sudden end of the scratching you had been hearing. The carcass is usually wedged on the smoke shelf just behind the damper, though we sometimes find them at flue offsets higher up. We locate the remains with an inspection camera, remove them through the firebox or from the top of the flue, and then do a full sanitizing and deodorizing treatment, which is the step that actually ends the smell. Skipping that treatment is why the odor lingers for weeks in homes where someone removed the carcass but stopped there.

How quickly can you get to my home?

Animal calls get priority scheduling because most of them are genuinely time-sensitive: a trapped squirrel is dehydrating, a blocked heating flue is a carbon monoxide risk, and a raccoon actively working on your damper is doing new damage every night. We serve Marlborough and communities across Greater Boston and Eastern Massachusetts from our shop in Melrose, and we can typically be on site the same day or next morning for an active animal situation. When you call (781) 653-5644, tell us what you are hearing and where, close the damper if it is safe to reach, keep the glass doors shut, and leave the rest to us.

Get It Handled Today

What you are really buying from a chimney company is the ability to stop wondering. No more second-guessing the flue every time you light a fire, no more eyeing that stain on the ceiling near the chimney, no more resolving each October to deal with it next year. One call to Upside Down Chimney Sweeps at (781) 653-5644 settles the question for your Marlborough home: a professional sweep, an inspection guided by NFPA 211, photographs of everything relevant, and recommendations ranked honestly by urgency. Most chimneys pass with minor notes, and their owners sleep better for knowing it. If yours needs work, you will know exactly what and why. Either way, the wondering ends.

Serving Marlborough Same-Week

Our Melrose shop is 32 miles from Marlborough. Call (781) 653-5644 for fast scheduling.

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