Chimney sweeping and creosote removal

Sweeping is the foundation of chimney maintenance and the service most people picture when they think of this trade. The job is to remove the combustible deposits that build up on the inside of a flue every time wood is burned, along with the soot, ash and debris that collect in the smoke chamber and on the smoke shelf.

Creosote forms when wood smoke cools on its way up the flue and condenses. It appears in three recognised stages. Stage one is a light, flaky soot that brushes away easily. Stage two is a harder, tar-like deposit that has to be removed with rotary tools. Stage three is glazed creosote — a shiny, hardened layer that behaves like a fuel coating on the inside of your chimney and is the direct cause of the majority of chimney fires. Glazed creosote cannot be brushed off; it requires chemical modification followed by rotary removal, and in extreme cases the liner has to be replaced.

Our sweeping process begins with containment. A sealed vacuum with HEPA filtration is fitted at the firebox opening and drop cloths cover the hearth and the surrounding floor. We then work the flue with rods from below, the roof, or both, depending on the construction, using poly or wire brushes sized to the flue and rotary whips where deposits are hardened. The smoke chamber and smoke shelf are cleaned by hand because that is where debris collects and where brushes alone will not reach. Finally the firebox is cleaned, the damper cleared and lubricated, and everything vacuumed down.

In Miami, sweeping frequency is driven by use rather than by season. A home that burns a few fires on cool evenings in January will build creosote slowly. A home with a regularly used outdoor fireplace, wood-fired pizza oven or an insert that gets real use needs sweeping considerably more often. The trigger point is the same everywhere: roughly one eighth of an inch of deposit means it is time.

Chimney inspections — Level 1, Level 2 and Level 3

An inspection is the only way to know the condition of a chimney, and it is the service we would choose if a homeowner could only buy one thing from us. The three levels are defined in NFPA 211, the national standard, and each has a specific trigger.

Level 1

This is the annual inspection for a system that is in continued service with no changes and no reported problems. We examine the readily accessible portions of the chimney exterior and interior, the accessible portions of the appliance and the connection between them, verifying that the structure is sound, that there are no obstructions, and that combustible deposits are within acceptable limits.

Level 2

Required whenever a property changes hands, whenever the fuel type or appliance changes, whenever a liner is added or altered, and after any event that may have damaged the chimney — a chimney fire, a lightning strike, hurricane-force winds, or a building settlement. A Level 2 includes everything in a Level 1 plus a video scan of the entire flue interior and inspection of accessible attic, crawl space and basement areas where the chimney passes through. It also covers clearances to combustible materials, the proper construction and condition of the flue, and the size of the flue relative to the appliance.

If you are buying a house in Miami with a fireplace, this is the inspection you want, and a general home inspector's visual glance at the firebox is not a substitute. Home inspectors are not required to scan the flue, and the flue is where the expensive problems live.

Level 3

Carried out when a Level 1 or 2 inspection suggests a serious hazard that cannot be confirmed without access to concealed areas. This may involve removing a portion of the chimney crown, a chase cover, or interior wall or ceiling material. It is invasive and we only recommend it when the alternative is leaving a genuine safety question unanswered.

Chimney and fireplace repair

Repair work covers the components inside the system that wear, crack, corrode or were built wrong to begin with. The most common repairs we carry out in Miami homes are these.

Firebox repair and refacing. The firebox takes direct flame and the most extreme thermal cycling in the system. Firebrick cracks and the refractory mortar between the bricks erodes, which allows heat to reach the masonry and framing behind. We cut out failed joints, repoint with refractory mortar rated for the temperature, and replace individual firebricks where the face has spalled. Where a firebox has gone too far, it is rebuilt from the floor up.

Smoke chamber parging. The smoke chamber is the funnel between the throat of the firebox and the base of the flue. Older chambers were built with corbelled brick left rough and unfinished, which creates turbulence, slows the draw and gives creosote a hundred ledges to settle on. Parging with a smooth refractory coating restores the intended shape, improves draw noticeably, and makes future sweeping far more effective.

Damper replacement. Throat dampers seize, warp and corrode, and in a coastal city they do so faster. Where the original frame is sound we replace the plate and seal. Where it is not, we fit a top-sealing damper at the crown, which has the additional advantage of sealing the flue against humidity, rain and animals with a silicone gasket — a far better seal than any throat damper achieves.

Throat and lintel repair. The lintel is the steel angle that supports the masonry above the fireplace opening. In houses near the water these rust, and rusting steel expands with enormous force, cracking the masonry it is embedded in. Replacing a corroded lintel is structural work and we do it properly, with temporary support and correctly bedded new steel.

Masonry restoration and tuckpointing

Tuckpointing — also called repointing — is the process of cutting out deteriorated mortar joints to a consistent depth and filling them with fresh mortar. It is the single most valuable preventative repair available for an older chimney, because sound joints are what keep water out of the structure.

The critical detail is mortar selection, and it is where most repointing jobs go wrong. Mortar must be softer than the brick around it. That sounds backwards, but it is why historic buildings used lime-rich mixes: when the structure moves or when salts crystallise, the mortar is designed to be the sacrificial element that gives way, because mortar is cheap to replace and brick is not. Repointing a soft 1930s brick chimney with a hard modern Portland mix guarantees that the next movement cracks the brick faces instead of the joints, and those faces do not grow back.

We assess the existing masonry, mix mortar to a matching hardness, and match the colour and the joint profile — concave, weathered, flush or raked — so the repair disappears rather than announcing itself as a stripe of grey across your chimney. On coral stone, keystone and oolitic limestone chimneys, which Miami has plenty of, we use compatible lime-based mixes and hand-finish to the existing texture.

Where individual brick or stone units have spalled beyond repair we cut them out and replace them with salvaged or matched units. Where a stack has deteriorated past the point where repointing is economical — usually when more than roughly a third of the face brick has failed — we will tell you honestly that a rebuild is the better investment.

Chimney crown repair and rebuilding

The crown is the concrete wash at the top of the chimney that sheds rainwater away from the masonry below. A properly built crown is a cast slab of reinforced concrete, at least two inches thick at its thinnest point, sloped away from the flue tiles, overhanging the brick by an inch or two, and finished with a drip edge on the underside so water falls clear of the wall instead of running back down the face.

Very few Miami chimneys have one. The overwhelming majority were finished with a thin mortar wash troweled flush to the brick — no reinforcement, no overhang, no drip edge. Mortar of that kind cracks within a decade, and after that every rainfall pours water directly into the top of the stack.

We repair crowns two ways depending on condition. If the structure is essentially sound with hairline to moderate cracking, we clean and prepare the surface and apply a flexible elastomeric crown coating that bridges existing cracks and moves with thermal expansion instead of cracking again. If the crown is structurally failed — large sections missing, deep cracks, separation from the flue tile — we demolish it and pour a new reinforced crown with a proper bond break around the flue tiles, correct slope, overhang and drip edge.

Crown work is close to the definition of a high-return repair. It is a fraction of the cost of the liner replacement, interior water damage and stack rebuild that follow from ignoring it.

Chimney caps, dampers and flashing

Caps. A chimney cap is a stainless steel or copper lid with a mesh spark screen that sits above the flue. It keeps rain out of the flue, keeps birds, raccoons and wasps out of the flue, and stops embers landing on your roof. It is the cheapest component on the chimney and the one whose absence causes the most expensive damage. We fit single-flue caps, multi-flue covers that shelter the entire crown, and custom-fabricated copper caps for houses where appearance matters.

Top-sealing dampers. Fitted at the top of the flue with a silicone gasket and operated by a stainless cable running down to the firebox, these seal far better than a cast iron throat damper. In an air-conditioned Miami house that seal is worth real money in energy terms, and it also keeps out the humid air that drives the summer fireplace smell.

Flashing. Flashing is the metalwork that seals the junction between the chimney and the roof, and improperly installed flashing is the most common cause of chimney leaks we attend. Correct flashing is a two-part system: step flashing woven into the roof covering course by course, and counterflashing cut into a mortar joint in the chimney, bent down over the step flashing, and mechanically secured. Sealant is a supplement, never the system.

On Miami's barrel tile roofs this detail is considerably more involved than on shingle, and it is routinely done wrong by crews without tile experience. If your chimney leaks and someone has previously "fixed" it with a bead of roofing cement smeared around the base, this is almost certainly your problem.

Chimney waterproofing and leak repair

Brick and mortar are porous. In a dry climate that is harmless; in Miami, where wind-driven rain is pushed horizontally against the stack for months at a time and where salt is carried in the air off the bay, it is the mechanism behind most chimney deterioration. Water enters the masonry, carries dissolved salts deeper, and when it evaporates those salts crystallise and expand, pushing the face of the brick off in flakes. That is spalling, and it is irreversible.

Waterproofing prevents it, but only if the right product is used. A film-forming sealer — anything that leaves a glossy or plastic layer — is worse than doing nothing, because masonry is always holding some moisture and a sealed surface traps it inside, where it freezes, or in our climate simply saturates and accelerates spalling from behind. The correct product is a vapour-permeable siloxane or silane water repellent. It penetrates the masonry, lines the pores so liquid water cannot enter, and still allows water vapour to escape outward.

Leak diagnosis is separate work and comes first. We locate the entry point with a controlled water test, wetting one component at a time — brick face, then mortar joints, then flashing, then crown, then cap — until the leak reproduces inside. Only then do we know what to repair. Waterproofing a chimney whose crown is cracked simply hides the leak for a season.

Chimney liner installation and relining

The liner is the pipe inside the chimney that carries combustion gases out of the house. It has three jobs: contain the heat, contain the corrosive and toxic products of combustion, and provide the correctly sized passage for the appliance to draw properly. A chimney with a failed liner is not a chimney that works slightly less well. It is a chimney that can allow heat and carbon monoxide into the structure, and it should not be used.

Clay tile liners, which almost every older masonry chimney in Miami has, fail by cracking. They crack from the thermal shock of a chimney fire, from gradual settlement, and from water getting behind them. Because the tiles are only mortared at the joints and are not sealed to the surrounding masonry, a single cracked tile creates a route for gases to leave the flue.

Relining is normally carried out with a UL-listed flexible or rigid stainless steel liner, sized from the appliance specification and the flue dimensions. For wood-burning appliances and for any flue where the exhaust would otherwise cool too fast, the liner is wrapped in a ceramic insulation blanket or poured insulation mix, which keeps the flue gas temperature up, improves draw and reduces creosote formation. The liner is connected properly at the appliance, supported at the top plate, and finished with a cap.

Relining also solves draw problems on chimneys that were built with a flue far too large for the fireplace — a common 1950s and 1960s error. Reducing the effective flue diameter to the correct size often transforms a fireplace that always smoked into one that works.

Gas fireplace and log set service

Gas appliances are far more common than wood in Miami homes and condos, and they are also far more often neglected, because there is no visible soot to prompt a call. They still need annual service, and the reasons are safety reasons.

A gas service visit covers the burner and burner ports, which clog with dust, spider webs and combustion residue and cause uneven or lifting flames; the pilot assembly, thermocouple and thermopile, which are the components that shut off gas flow if the flame fails and which degrade steadily with use; the oxygen depletion sensor on vent-free units; the gas control valve and its connections, checked for leaks; and the log placement, which must match the manufacturer's diagram exactly, because a log sitting in the wrong position produces soot and carbon monoxide in an appliance designed to produce neither.

On direct vent and sealed units we also service the glass and the gasket. A perished gasket breaks the seal that makes a direct vent appliance safe, and clouded glass is usually a sign of incomplete combustion rather than a cleaning problem. Finally we inspect the venting itself — the coaxial pipe or B-vent run — for corrosion, separation at the joints, blockage and correct termination clearance.

Dryer vent cleaning

Clothes dryers cause thousands of house fires a year in the United States, and failure to clean the vent is the leading cause. In Miami the problem is compounded by long duct runs in condominiums and townhouses, by humidity that makes lint clump and stick, and by flexible foil ducting that traps lint in its ridges.

The symptoms are easy to recognise once you know them: clothes taking two cycles to dry, the dryer cabinet hot to the touch, a burning smell during operation, the laundry room feeling humid, and the vent flap on the exterior wall not opening when the dryer runs. Any of these means the duct is restricted.

We clean the full length of the duct with a rotary brush system driven from both ends where access allows, capture the debris with a vacuum rather than blowing it into the room, clean the dryer's internal lint trap housing and blower area, and then test airflow at the exterior termination so you have a measured before-and-after figure. Where the duct itself is the problem — foil flex, crushed sections, excessive length, too many elbows, or a termination that vents into a soffit or attic instead of outdoors — we quote for replacing it in rigid metal.

Animal removal and chimney exclusion

An uncapped flue is, from a bird's point of view, an ideal cavity: sheltered, vertical, warm and completely inaccessible to predators. Raccoons find them equally attractive as den sites, and in Miami we regularly find wasp and bee colonies established in flues that have not been used for years.

We remove nests, debris and — where an animal is present — arrange humane removal before any work continues. Once the flue is clear it is swept, inspected for damage caused by nesting material and droppings, and then capped with a stainless steel cap and spark screen so the problem cannot recur. Exclusion is the permanent fix; removal alone simply resets the clock.

Nesting material is also a serious fire hazard. A flue packed with twigs directly above a firebox is an obvious risk, but the less obvious one is partial blockage, which pushes combustion gases back into the house rather than up the chimney.

Outdoor fireplaces, fire pits and pizza ovens

Outdoor living space is where South Florida actually uses fire. We build, repair and maintain outdoor masonry fireplaces, wood-fired pizza ovens, built-in barbecues and fire pits, and the maintenance requirements are higher than most owners expect because these structures are exposed to weather continuously with no roof over them.

Typical work includes refractory repair inside the oven or firebox, hearth and chimney repointing, crown and cap work on outdoor flues, stucco and stone repair on the surround, and sweeping — a pizza oven used weekly accumulates deposits far faster than an indoor fireplace used six times a winter. We also correct draw problems on outdoor fireplaces, which are common because they are frequently built by general landscape contractors without the flue proportions that make a fireplace actually vent.

Chimney rebuilds and removal

Some chimneys reach the point where repair is no longer the economical answer. When face brick has spalled across most of the stack, when the structure is out of plumb, when the liner and crown have both failed, or when water damage has reached the framing, a rebuild produces a better result for less money than a series of patches.

We rebuild from the roofline up where the damage is confined above the flashing, and from the foundation where it is not. Rebuilds are carried out to current Florida Building Code including the high-velocity hurricane zone requirements that apply in Miami-Dade, with new liner, new crown, new flashing and new cap installed as part of the work rather than reused.

Where a chimney is no longer used and the owner would rather not maintain it, we also carry out full removal, including structural make-good, framing, decking and a weather-tight roof closure.

Emergency and storm response

Available 24 hours a day, every day. After a chimney fire we carry out the Level 2 inspection your insurer will require, document the damage thoroughly, and make the structure safe. During and after named storms we attend leaks, dislodged caps, cracked crowns, lightning damage and debris blockages, and we can tarp and temporarily seal a chimney to stop water entry until permanent repairs can be scheduled.

If your carbon monoxide alarm has sounded, leave the property and call the fire service first. Once the property is safe, call us at +1 305-776-6451 and we will inspect the venting to find the cause.