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                                      FREQUENTLY ASKED CHIMNEY QUESTIONS,  SAFETY TIPS & GLOSSARY OF TERMS :                                    

How often do I sweep my chimney ?  After  burning a cord of wood or 30 Dura-Flame logs . The National Fire Protection Agency recommends a chimney should be swept annually for safety purposes     

What if I don't have a fire place ?  Most homes have a chimney flu serving the heating  system  un-swept oil flues and gas flues can be a carbon monoxide threat  in addition to fire  hazard.

How often should I have my chimney inspected ? The National Fire Protection Association recommends that you have your chimney inspected yearly (source:  NFPA Code 211).

How will you sweep my chimney? -With Care and Neatness most certainly!  We sweep UP mostly from the fireplace to allow most of the soot to rise up and  out of the chimney as much as possible and down from the rooftop when sweeping the heating appliance flues to the clean out door and  or heating appliance piping connection  with traditonal  style brushes and  fiberglass rods. We augment sweeping  with a high powered 16 HP commercial Vacuum to eliminated any dust soot or debris leaving the firebox. By sweeping from the bottom up we can control how fast we sweep by viewing how much soot is falling, However in some instances we will sweep from the top down as necessary. We usually come with a crew of two who use drop cloths and rug runners. Our staff is personable professional and polite causing as little intrusion as possible.

Do I need a rain cap for my chimney? Properly sized rain caps keep out animals, leaves and masonry destroying water and prevent spark from igniting combustibles in the area  

What is a chimney liner? A flue lining in a masonry chimney is defined as "A clay, ceramic, or metal conduit installed inside of a chimney, intended to contain the combustion products, direct them to the outside atmosphere, and protect the chimney walls from heat and corrosion." Although building codes vary from one locality to another, the installation of flue lining has been recommended since the early part of this century, and indeed most fire codes now mandate liners. In the 1940's and again in the 1980's, masonry chimneys were tested by the National Bureau or Standards for durability due to rising concerns about their performance and safety. The tests revealed that unlined chimneys were so unsafe that researchers characterized building a chimney without a liner as "little less than criminal".

Clay Flue Tiles       Stainless Steel  SS flue liner  Unlined Masonry Flue unlined flue

What function does a liner serve? Firstly, The liner protects the house from heat transfer to combustibles. In the NBS tests, unlined chimneys allowed heat to move through the chimney so rapidly that the adjacent woodwork caught fire in only 3 1/2 hours. Secondly Liners protect the masonry from the corrosive byproducts of combustion. In the tests it was determined that if the flue gases were allowed to penetrate to the brick and mortar, the result would be a reduction in the usable life of the chimney. The flue gases are acidic in nature and literally eat away at the mortar joints from inside the chimney. As the mortar joints erode, heat transfers more rapidly to the nearby combustibles and dangerous gases such as carbon monoxide can leak into the living areas of the home. Lastly Liners provide a correctly sized flue for optimum efficiency of appliances. Modern wood stoves and gas or oil furnaces require a correctly sized flue to perform properly. The chimney is responsible for not only allowing the products of combustion a passage out of the house, but the draft generated by the chimney also supplies the combustion air to the appliance. An incorrectly sized liner can lead to excessive creosote buildup in wood burning stoves, and the production of carbon monoxide with conventional fuels

How Much does a liner installation cost? Installation cost depends variables such as of length and width and most importantly type of material used to accommodate the BTU's and flue gases from the appliance and length of the chimney and liner material  needed, degree of difficulty to install i.e., peak of roof or a flat roof, if the chimney is a straight shot or has offsets, jags or turns and amount of piping needed to tie into appliances or a fireplace. In General we are usually several hundred dollars less than our qualified friendly competitors and always competitvely priced..

My house is 1906 vintage, and a chimney sweep recently told me that I had a serious hazard because of not having a lining. Evidently buildings constructed before 1924 did not have them. Any comments?

In the early part of the past century, fireplaces were really heaters. The fuel was usually coal, but these fireboxes would support a small wood fire. The next time an opportunity presents itself, take a good look at a firebox in a Victorian-era building. What you'll see is a shallow firebox with an angled back wall. The heat produced by a small coal or wood fire was deflected into the room rather than up the chimney, as would be the case with a deeper firebox. We're not surprised that a 1906 home is equipped with an unlined masonry chimney. Widespread use of flue liners did not occur until later.

The lack of a liner does not necessarily mean that the chimney creates a serious hazard. If the mortar between the bricks is sound, it may be OK. But, because of the age of the chimney, it is more likely than not that flue gases from 100 years of fires have played havoc with the brick and mortar, compromising the chimney. We think you would be well served to investigate having a flue liner installed. Think of it as an investment in your safety.

We assume that your chimney sweep did a thorough inspection of the firebox and chimney before saying it was unsafe. His inspection probably revealed cracked and deteriorated mortar joints between the bricks of the chimney.

Failed mortar joints can result in two serious safety hazards. Carbon monoxide can leak into the house through voids in the masonry, also heat and sparks from a fire can penetrate through these cracks and set fire to the wood framing of the house.

Fire is more likely if there is creosote buildup on the interior of the chimney. Creosote is a sticky, flammable byproduct produced by insuficient combustion of wood products, burningmagazines,trash, unseasoned soft woods such as pine and Douglas fir. It coats the walls of the chimney and saturates the mortar. If the creosote is ignited in the chimneyit creates and intense heat the chimney was never designed for, also there is a very real possibility that flames and heat will migrate from the flue to the framing, causing a catastrophic house fire!

Flue liners protect the house from heat transfer to combustibles. They also protect the masonry from the corrosive effects of flue gases. Flue gases are acidic and eat away the mortar joints of unlined chimneys.

There are three types of flue liners. The most common material used is clay tile. They are installed in sections and mortared together. The weak link of this system is the mortar and the tiles themselves deteriorate over time. Mortar is susceptible to decay caused by flue gases. In addition, clay tile cannot rapidly absorb heat and evenly distribute it, so they are subject to cracking.

Metal flue liners made from stainless steel are primarily used to upgrade and repair existing chimneys. These liner systems are tested and listed by the Underwriter's Laboratory (U.L.), and if properly installed and maintained (a yearly cleaning) are safe and durable.We use, depending on the application, type 304,316 and special AL294C Stainless Steel Alloys in all our liner installations

Finally, cast-in-place chimney liners are lightweight concrete-like products that are installed inside a chimney, forming a smooth, seamless, insulated passageway for flue gases to be vented to the outside. As an added bonus they can improve the structural integrity of aging chimneys.

Whether you decide to have your 1906 chimney relined depends in large part on the condition of the chimney and how much you use your fireplace. We suggest that you err on the side of caution and consider installing a flue liner.

How can I preventing Carbon Monoxide poisoning? Carbon monoxide (CO) is a colorless, odorless, tasteless, and deadly gas. When exposed to CO, it restrains your blood's capacity to carry oxygen throughout the body, actually suffocating your tissues and organs. CO can escape into your home's air through a faulty furnace, wood-burning stove, range, water heater, fireplace, or any device that burns combustible fuel. CO poisonings from fuel-burning appliances kill at least 200 people a year and send more than 5,000 people to hospital emergency rooms. Carbon monoxide poisoning symptoms can often be confused with flu symptoms but become much more serious. Symptoms include headache, fatigue, nausea, dizziness, irregular breathing, mental confusion, unconsciousness, and ultimately - death. The key to protecting yourself and your family is prevention and the use of a quality carbon monoxide detector. Though everyone is susceptible, medical experts believe that small children, pregnant women, unborn babies, senior citizens, and people with heart or respiratory problems are more vulnerable. To avoid CO poisoning in your home, As of March 31, 2006, all homes in the Commonwealth of Massachusetts equipped with fuel burning equipment that produces carbon monoxide or which have indoor parking (a garage) adjacent to living areas will be required to have Carbon Monoxide detectors installed. The law, and the regulations that implement it, apply to ALL homes and not just those that are being sold. Below are some frequently asked questions by home owners and some following suggestions:

As a Homeowner in the Commonwealth, what do I need to do to comply with this new law? Prior to March 31, 2006 you must install a carbon monoxide detector on every level of your home, excluding unfinished basements, attics and crawl spaces. Detectors that are installed on levels of the home which contain sleeping areas must be placed within ten feet of the bedroom door; therefore some homes may require more than one detector on certain levels. However, for those property owners who choose to install hardwire detectors, the deadline for compliance is not until January 1, 2007 provided they file a notice of intent to install hard-wired unit(s) with the local fire department by May 15, 2006.

How can you protect against carbon monoxide poisoning?

  • Have your furnace and fireplace cleaned and inspected before each heating season. Have other fuel burning appliances checked regularly.
  • Use non-electrical space heaters only in well-ventilated areas.
  • Do not start or idle gas lawn mowers, cars, trucks, or other vehicles in an enclosed area, even with the garage doors open.
  • Vent fuel-burning appliances outside whenever possible.
  • Do not ever use a charcoal grill inside your home, garage, tent, or camper.
  • Do not use portable heaters or lanterns while sleeping in enclosed areas such as tents, campers, and other vehicles. This is especially important at high altitudes, where the risk of CO poisoning is increased.
  • Read and follow manufacturer instructions and precautions that come with any fuel-burning device.
  • Do not ever use a gas oven for heat inside your home.
  • Use an approved carbon monoxide detector with an audible alarm inside your home

What kind of Carbon Monoxide Detectors must I install in my home & how should I install a Carbon Monoxide Detector?

The law provides a choice to homeowners to install, by March 31, 2006, their choice of either battery operated, plug-in with battery back-up, wireless detectors, a combination smoke/carbon monoxide detector, or hard-wired detectors. These detectors must be in compliance with Underwriter Laboratories (UL) standard 2034. The package the detector is sold in will indicate whether it meets this standard. CO alarms should be installed according to the manufacturer's instructions. Note: There are specific requirements for combination alarms, before purchasing one please review the requirements of combination alarms with your local fire department. Like its inspections for smoke detectors, the local fire department is required to inspect each dwelling for compliance with the carbon monoxide law before sale.

We plan to build a new home in 2007, are there additional requirements for new construction? Are there any other laws I should know about? The state building code will govern additional requirements for new construction. It is believed that it will require hardwired carbon monoxide detectors for new constructions or for homes who undergo substantial renovations. More information about the state building code may be obtained at Currently, there are certain plumbing regulations which may require a hard-wired CO detector to be installed with certain appliances. For more information check with the plumber who completes your installation. It is possible that your local city or town might have enacted stricter requirements, therefore you should check with your local fire department.

Every time a fuel appliance is activated, CO is produced. Keep fresh air circulating in your home; open a vent or a window to eliminate toxic fumes. Fuel-combustion appliances should be vented directly outdoors.

The Consumer Product Safety Commission also recommends installing at least one carbon monoxide detector with an audible warning alarm. Choose Underwriters Laboratories (UL) listed detector that sounds an audible warning. Look for the UL logo on the package. 

Install your CO detector at least 15 feet away from a furnace or gas appliance. Avoid installing detectors close to a fan, swamp cooler, or other fresh or turbulent air sources as this may deter the unit from taking accurate readings. If you only have one detector, it should be installed in the hallway near the sleeping area so it will awaken you if the alarm goes off while you are sleeping. Additional alarms on each level of your house can provide extra protection and by bedroom doors. 

Maintain CO detectors on a regularly basis. Keep it clean and free of grease, soot, and debris - clean it with a slightly damp cloth (no chemical cleansers) or vacuum it. It's best to test your alarms regularly as well. 

Have your heating system checked each fall before cold weather arrives to make sure it's operating efficiently and all the vents, pipes, flues, and chimneys are unclogged and tight. Have your stoves, fireplaces, and water heater checked as well. 

Don't close your fireplace damper until you're certain the fire is out. If smoke enters the room, your chimney may be causing a reverse flow. Open a window. Have all chimney cleaned, inspected and serviced annually. 

Never run your car engine in an enclosed area - open the garage door before starting the car. 

Replace smoke alarms every ten years - they accumulate significant levels of dust, dirt, and debris. Since a smoke alarm works 24 hours a day, seven days a week, its life span is about ten years. 

Make sure the burner flames on your furnace burn blue, not yellow-orange, and never use your gas or oven for heating. 

Never use grills or hibachis inside your home. 

Never operate gas-burning appliances in a closed room. 

How can I develop a Fire Escape Plan? Making a plan and holding regular fire drills will give each household member the confidence and knowledge to act quickly in an emergency. Here then are some tips on developing a family escape plan: Sketch a layout of each floor, including windows, doors, and stairways. Go over the plan with family members and post it in your home as a reminder of all possible exits. Keep the phone number of the Fire Department handy by the phone. Have family members practice different escape routes (at least two per room). Fire drills also teach children that they must escape, not hide from fire. Place one family member in charge of helping the elderly or the very young to escape. Agree on a meeting place outside the home and instruct everyone to go there in case of fire. Discuss why you shouldn't go back inside once you're out. (People have died returning to a burning building). Nearly one-third of home fire victims lost their lives in fires that were smoking-related. If you have a smoker in your home, install a smoke and fire alarm in his or her room and have large, heavy ashtrays placed in various locations.

Occasional smoking problems

Constant smoking problems

Other Types of Smoking Problems

Link - Bob Villa on Chimney maintenance and liners - a job best left to the pro's

Glossary of Terms :

Carbon Monoxide An odorless, colorless, tasteless poisonous gas that is a byproduct of incomplete combustion.

Cast Aluminum A light weight, rust proof metal made by pouring molton aluminum into pre-shaped molds or casts.

Chimney A structure made of masonry or metal, which surrounds and supports the flues that vent products of combustion from gas, oil, or solid fuel appliances or fireplaces. 

Chimney Caps Protective coverings for chimneys usually made of aluminum, galvanized or stainless steel, or copper. Most chimney caps have a mesh screening that serves the dual purpose of spark arrestor and barrier against animals. Chimney caps also prevent rain from entering the flue of the chimney.  

Chimney Cleaning The process of removing soot, creosote, and debris from a chimney. This should be done on a regular basis in order for the chimney to operate as efficiently and safely as possible.

Chimney Damper Caps Chimney dampers with caps are mounted to the top of the chimney and are a device which replaces traditional throat dampers and have caps to protect them from weather.  

Chimney Liner The inner portion of the chimney that contains the products of combustion. It can be made of clay tiles or of metal. For flues to be serviceable, they must remain in tact, free from perforations, cracks or damage of any kind that could allow the products of combustion to pass into the living spaces of the home, or the heat from the products of combustion to endanger combustible materials near the flue such as framing, walls, ceilings, insulation, or floors. 

Chimney Relining The inner portion of the chimney that contains the products of combustion. It can be made of clay tiles or of metal. For flues to be serviceable, they must remain in tact, free from perforations, cracks or damage of any kind that could allow the products of combustion to pass into the living spaces of the home, or the heat from the products of combustion to endanger combustible materials near the flue such as framing, walls, ceilings, insulation, or floors. 

Chimney Repair The process of restoring broken or damaged chimneys to service. This can involve tuckpointing loose brickwork, rebuilding or resealing the crown, or relining the chimney when the chimney liner is cracked, perforated, or broken. 

Chimney Service A professional company that cleans, inspects, repairs, evaluates, and maintains chimneys. 

Chimney Sweep A professional who makes his/her living cleaning, inspecting, repairing, and maintaining chimneys.  

Damper Cable That part of a top-sealing damper that runs from the damper down the chimney to the firebox. It has a handle on the firebox end for the purpose of opening and closing the damper. 

Energy Loss Heated or cooled air lost from a home to the outside environment through the walls, seals around doors and windows, and/or up the flue of a chimney. 

Firebox The location in a fireplace where the fire is built and contained. The firebox is constructed on the inside of a special kind of brick manufactured for its refractory qualities and its ability to withstand high temperatures. 

Fireplace A device of either metal or masonry construction open on at least one side, designed to contain a fire. These can be for outdoor use such as cooking and barbeque, or for indoor use for ambiance and some heat. 

Fireplace Inserts Wood, coal, pellet, or gas heating appliances that fit inside an existing fireplace. 

Fireplace Mantel That part of a hearth setting that protrudes from the surface above the opening of the fireplace and is usually used as a shelf. If made of combustible material, it must be far enough above the fireplace opening to meet NFPA standards. 

Fireplace Opening That portion of the fireplace open to the surrounding area. 

Fireplace Smoke Chamber That portion of the fireplace located above the firebox and at the base of the chimney flue where smoke gathers before it is exhausted up and out of the chimney. 

Fireplaces Devices for indoor burning, open on at least one side. Most often of masonry or metal construction built with the home. Most commonly used for burning wood for effect rather than heat source. 

Flue Any device used for containing and venting the products of combustion from gas, oil, or solid fuel appliances or fireplaces. Also, the inner part of a chimney that contains the products of combustion from gas, oil, or solid fuel appliances or fireplaces. Flues can be made of clay tiles or of metal. 

Gas Stoves Heating or cooking appliances that use natural gas or liquid propane as their fuel. 

Hearth The area directly in front of the opening of the fireplace usually constructed of masonry or other heat resistant material for the purpose of shielding the floor from excessive heat. 

High-Efficiency Furnace A heating device that returns to the heating environment more than 90% of the heat it generates. Such a device has, therefore, relatively low flue gas temperatures. The lower flue gas temperatures result in more moisture that condenses on the interior flue walls. This situation significantly increases the opportunity for corrosion within the flue. 

Low-Efficiency Gas Furnace A heating device that returns to the heating environment less than 90% of the heat it generates. Such a device has a warm enough flue gas temperature to allow for the vaporization and release to the environment most of the moisture created in the combustion process. This allows for a flue gas environment that is substantially less corrosive than that created by a high-efficiency gas furnace. 

Throat Dampers Metal plates installed just above the firebox of a masonry chimney that are used for sealing the flue shut when the fireplace is not in use. Since they seal metal to metal, the seal is quite leaky even when the plates are new. Over time, the plates rust and deteriorate as they are exposed to heat and moisture. When this happens they lose almost their entire flue sealing capacity. 

Top-Sealing Damper A device installed at the top of a chimney for the purpose of sealing the flue shut when the fireplace is not in use. They are often used as replacements for throat dampers that are installed just above the firebox when a masonry chimney is built. Lyemance and Lock-Top top-sealing dampers are as much as 90% more efficient than throat dampers because they provide a silicone rubber gasket seal rather than metal to metal. 

Woodstoves- Enclosed appliances, most commonly constructed of steel or cast-iron, used for burning wood for the purpose of heating an indoor space.


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