Fireplace: causes & how to avoid

Figure 1 – View of a typical “zero clearance” hearth, the red arrows illustrate safety supports slightly far from the fuel material (wooden frame) above the Foyer’s combustion chamber.

Damage caused by chimney lights: causes, responsibility, reminders and security

Domestic heating equipment is the main cause of domestic fires in the United States during the months of December, January and February. Period during which almost half (48 percent) of all fires due to domestic heating equipment in the United States are held. January is the period when there are the most fires due to domestic heating equipment; A fifth (20 %) of all fires due to domestic heating equipment takes place during this month.

According to the latest statistics relating to the NFPA heating equipment, on average 48,530 fires due to domestic heating equipment took place each year between 2014 and 2018, causing around 500 civil losses, 1,350 injuries and 1.1 billion dollars direct material damage. During the coldest months of the year, when we see the greatest number of fires due to domestic heating equipment, it is essential that people understand when and where fires due to domestic heating equipment tend to occur so that they can take the necessary measures to reduce these risks.

Domestic homes and corresponding chimneys are the source of almost half of these fires. The chimneys have been used for centuries and are a great way to add heat and atmosphere to any house, but there will always be special considerations when using a bare flame to create heat.

The subject of this article aims to discuss the domestic fires caused by fireplace and households and to approach the key axes of the study, which are:

• How the fireplace and home fires occur and which can be responsible for it
• Types of foci according to design and construction
• Factory chimney regulation
• Frequent installation errors
• Reminders about chimney inserts
• General security applied to chimneys

How and where accidental fire and chimney fires occur ?

The majority of fires associated with households take place at the level of the fireplace and not in the combustion chamber. Among these chimney fires, there are mainly three common causes. The first is the accumulation of creosote on the wall of the chimney. The Creosote is created by the fuel not burned of smoke, when it circulates through the fireplace. When hot smoke circulates through the chimney, it creates a condensation on the wall of the chimney due to a temperature difference and creates an undesirable fuel load layer. Creosote is a dark substance, similar to tar, very sensitive to inflammation.

The Creosote is highly fuel and is well known for its threat of fire in the fireplaces of wooden households. The Creosote ignition point (the lowest temperature to which the vapors will ignite near a source of fire such as a spark or a flame) in the form of liquid has been measured below 165 degrees fahrenheit (f) . A spark, a fiery embers or a flame that increases the temperature of the liquid creosote at 165 ° F can ignite the creosote in a fireplace. The self-removing temperature of the dry creosote was measured at 451 ° F, similar to that of paper.

A second potential cause comes from a defect in the wall or the fireplace of the chimney due to poor installation or a design defect. It doesn’t matter if the fireplace is brick, stone or metal; If there is a direct or indirect means of contact with heat or flame on fuels, a fire can be triggered.

The third common cause of fires is the release of sparks or chimney embers to the surrounding fuels inside a structure or outside, such as a roof. All combustible materials (furniture, etc.) must be placed in at least three feet of the opening of a home.

Which is responsible for accidental fire and fireplace fires ?

The parties that can be responsible for fire fires include:

• The manufacturers – Due to inadequate assembly and design instructions.
• Household installers – Due to poor installation of the combustion box or the chimney flue.
• Masons – Due to an inadequate or defective construction of the masonry of the fireplace and the home.
• Insulation installers – Due to the placement of insulation on or near a chimney duct.
• The architects – Due to a defective design or placement of homes and chimneys.
• Entrepreneurs General , supervisors , Gas component installers Or electricians – Due to poor supervision, installation or repair of a home or fireplace.

Other professional parties whose professional responsibilities require a duty of diligence include:

• Summons, homes inspectors or dwelling inspectors – in the event of inappropriate or inappropriate cleaning or detection/processing of an obvious danger.

Types of households

The majority of households are either built by masons or free of clearances. The foci built by masons are generally built in bricks or stone, with households made in the same material, which creates a solid barrier between the home and building materials. In general, the combustion boxes for masonry foci contain little or no metal and may have doors or not. On the other hand, zero clearance homes are fire -resistant combustion chambers so that the (zero) clearances are not necessary between the combustion chamber and the building materials such as the wooden frame and the plaster.

Zero clearance homes are made in factory with sheet metal or melting. They are also called “prefabricated foci” because they are delivered ready to install. Zero release foci are so named because they are isolated enough to be installed near combustible materials, such as wooden or wooden frames without the need for a masonry foundation. Many complexes of apartments and condominiums are built with a zero release home. Some have glass doors and others only have spark bumper.

Figure 1 – View of a typical “zero clearance” hearth, the red arrows illustrate safety supports slightly far from the fuel material (wooden frame) above the Foyer’s combustion chamber.

How are prefabricated homes regulated ?

Prefabricated homes are tested and listed by organizations such as Underwriters Laboratories (UL) and the Canadian Normalization Association (CSA). UL 127 determines the rules of chimneys made in factory. This includes the combustion chamber, the chimney, the assembly of the roof and other associated parts. The National Fire Protection Association (NFPA) also regulates chimneys via the NFPA standard for chimneys, homes, vents and solid fuel combustible appliances of the NFPA 211, as well as a section covering fixed fans and other accessories electricity covered by the National Electricity Code, NFPA 70.

The NFPA 21 standard governing chimneys, homes, vents and solid fuel devices stipulates the following:

• 14.2 annual inspection. Chimneys, homes and ventilations must be inspected at least once a year in accordance with the requirements of section 15.2
• 14.2.1 cleaning, maintenance and repairs must be carried out if necessary
• 15.2 type of inspection. The scope of the inspection, the areas of the chimney examined and the degree of invasiveness of the inspection must be adapted to the conditions giving rise to the inspection.
• 15.3.2.4 The inspection must include verification that the inspected duct is free from combustible (creosote) and obstructions deposits.
• 15.3.2.7 Interior surfaces of households and smoke chambers should be examined to detect damage and deterioration, combustible deposits and operating defects.

The International Code Council (ICC) also has regulations for construction standards in several of the code books, including building, residential sector, existing buildings, fire and mechanical.

Construction ICC codes and the residential area devote chapter 10 to fireplaces and homes, with a section on chimneys made in factory. The mechanical code addresses the chimneys in chapter 8 and governs the installation, maintenance, repair and approval of chimneys, chimney shirts and connectors. Gas devices are treated in the International Fuel Gas Code code book. The fire prevention code has definitions in chapter 2 and covers the chimneys in chapter 603.2:

603.2 chimneys. Masonry chimneys must be built in accordance with the International Building Code. Factory chimneys must be installed in accordance with the International Mechanics Code. Metal chimneys must be built and installed according to the requirements of NFPA 211.

The CSIA (Chimney Safety Institute of America) indicates that owners must inspect the homes and chimneys and clean them when an eighth thumb accumulation is obvious or visible inside the fireplace and the system evacuation. It also indicates that the fireplace and the home must be cleaned when less than an eighth inch of soot is visible in the combustion box or the fireplace.

Common errors in the installation of chimneys

Even if a design defect and lack of maintenance are often the causes of fires, an often neglected cause is the installation lack, including current errors such as:

• Framework – Combustible materials can set fire if they are placed too close to the home, which breaks the construction standards and the installation requirements of manufacturers. The protection of adjacent combustible materials must provide for the low resistance of wood and other fighter fire materials if they are exposed to continuous heat even at moderate temperatures. When wood is exposed to heat over a given period, its molecular structure undergoes a progressive change through a process called pyrolysis. The complex organic molecules of wood are slowly decomposed and most of the weight and structural integrity of the original wood is lost. As the process continues, the residual material is coal, which is also known by the more disturbing and technically correct term “pyrophic carbon. »Pyrophic carbon is different from wood and its properties are different. Its ignition temperature is considerably lower than that of the original wood. Many studies have set this temperature from 200 to 250 ° F. The hidden areas such as floor/ceiling assemblies and wall penetrations are particularly vulnerable, and the heating mode of the chimneys probably contributes to the problem. The wood exposed in these circumstances turns into pyrophic carbon and is “ready” to burn. Often, an unusual incident, such as accidental overheating, is the source of ignition. The temperature produced by the chimney should not be extremely high. A 200 ° F increase and carbon self-heating properties may be enough to cause combustion.
• The coat – If it is installed too low or too close above the combustion chamber, the coat of the chimney can take fire.
• Finishing materials – Combustible materials are often used in places that require non-combustibles. Paper on dry partitions, for example, can be a fuel material.
• The entrance to the gas duct – The gas duct entrance must be properly sealed with a high temperature putty.
• Conduits – The duct must be of adequate size; If it is offbeat, its size is reduced.
• Gas log sets – If the gas logs are too large or installed too forward, they may have a risk of fire and burning.
• Chimney hats – In the event of the use of metal protections, these cannot be built around the termination cap, unless authorization of the manufacturer.
• Cellulose insulation – Cellulose insulation products should never be in direct contact with the fireplace of a combustion apparatus, a vent or a duct, or against or on a built -in light or its case without CI (isolated contact). Most fire prevention codes require a minimum space of two inches between combustible materials and masonry chimneys, and certain types of triple wall evacuation pipes. For a single-wall evacuation pipe, these minimum clearances compared to combustible materials increase considerably to eighteen inches. For double -walled pipes, these clearances are generally reduced to nine inches for “L” type pipes for oil and solid fuels, and six inch for “B” type pipes for gas. (Always see the manufacturer’s recommendations and regional construction codes to find out specific use and regulatory requirements).

Fireplace inserts

The CPSC (United States Consumer Product Safety Commission) recalled the following chimney inserts:

• Jotul North America – 1,200 units
  The focus jotul and scan inserts were recalled due to the risk of contact between wiring and the metallic signage plate on the insert, which presents a risk of electrocution and burn.

Fireplace: causes & how to avoid

A third of fires are caused by a chimney fire. Then take your precautions in time. By regularly sweeping the fireplace and renovating it when it pulls badly, you decrease the risk of a fire. Read in this article all the causes and dangers of a fireplace and find out how to avoid it.

Causes fireplace

A chimney fire occurs most often in wooden chimneys or charcoal or mazout stoves. This combustion leaves soot in the smoke duct which can ignite. Gas stoves bring a risk of lower fire since no fouling is part of the conduits.

Leaves fallen into the chimney can also easily ignite, just like bird nests above the fireplace. When your fireplace is no longer doing well and smoke enters the house, this are signs that it is time to sweep your fireplace to avoid a fire. Contact a chimney sweep here.

Hazard

A poorly maintained chimney can cause co -co -length. The symptoms of such poisoning are: vertigo, nausea, desire to vomit, always when you enter a certain room. These symptoms disappear then as soon as you leave the room. CO poisoning can have serious consequences going difficult to breathe in losing consciousness and even death.

When it actually results in a fireplace, this can spread to the rest of the house with all its consequences.

Avoid a fireplace

The dangers mentioned above must then be avoided at all costs. This is possible by regularly sweeping your fireplace or repairing it in time where necessary.

1) Save the fireplace

For your own safety and health, it is advisable to regularly have your fireplace sweep. When the chimney pulls badly and the smoke enters your room, there is clearly a problem. In this case, you must immediately contact a chimney sweep. Even better is to prevent this problem and have your fireplace sweeps before there are problems.

In some cases, it is even mandatory to have your fireplace bloom at least once a year. In Wallonia, sweeping is compulsory when the fireplace is connected to a heating installation on liquid or solid fuels such as fuel oil or wood.

The best period to sweep your fireplace is just before the heating season, so before the coldest period of the year.

Chimney sweeping price: € 60 – € 100 for a duct
»Receive a tailor -made price.

2) Repair fireplace

When he enters smoke in the room when you heat, there is clearly a problem. A fireplace that pulls badly may be due to worn or poreus seals. Repair the joints is done without major work and prevents the headlines with a fire and causes a fire in this way. Read here more on the repair of the chimney.

Fireplace repair price: ± € 40/m² for repairing joints; ± € 12.5/m² to replace bricks.
»Receive a tailor -made price.

3) Maintain heating installation

As already mentioned in point 1, it is compulsory to execute an annual sweeping when the fireplace is connected to a heating installation on a liquid or solid fuel. When you carry out a cleaning of the heating installation at the same time as the fireplace, you decrease the risk of a fireplace fire.

Individual heating installations should not be cleaned each year, but it is still possible that your insurance requires it to be able to cover you in the event of a fireplace.

Fireplace cleaning price and heating installation: ± € 100 – € 150/m²
»Receive a tailor -made price.

4) Place fireplace

When your fireplace is difficult to reach and in this too little sweeping way, you can put a chimney hatch. This is a hatch in another place than at the top of the chimney. It is then easy to reach the chimney and remove the accumulation of soot.

Ramonal fireplaces

Sweep your chimney increases your safety. SUIE residues are cleaned in this way so that they can no longer ignite. A clean fireplace also has as a result that you can heat more efficiently which is a great advantage for your energy bill.

In addition, it is better for the environment to regularly sweep your fireplace. Fewer suspended particles then enter the air.

Insurance intervention in the event of chimney fire

Insurance is only involved when you have swept your chimney in compulsory times (once a year for chimneys connected to central heating, and regularly when it comes to an independent installation). In addition, this sweeping must be executed by a certified chimney sweep which gave you a bailed certificate. This certificate confirms that your fireplace was sweeten in accordance with standards. Easily contact an approved chimney sweep from your region.

Request quotes: chimney sweeping

Via the form below, you can request quotes from sweeps near you. Describe your project and you will quickly receive up to 3 quotes. This service is completely free and does not commit you to anything !

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Seasonal advice

A chimney fire emits a lot of toxic fine particles (PM10), especially when ignition. There are tips to know to limit air pollution at home and outside.

A good chimney fire can revive the atmosphere of a gloomy day. But, if there is no smoke without fire, you must avoid producing it. Indeed, smoke is a sign that wood burns badly and the hearth gives up in quantity of toxic and carcinogenic fine particles (PM10). They are obviously unwelcome in the room where we make fire, but also outside, and especially during cold and covered days, because the atmosphere is already loaded by the PM10s of heating and motorized traffic installations: In urban areas, their concentration then often exceeds the limit values, fixed by the federal order on air protection (opair). All fireplace therefore increases pollution. But you can limit the damage by doing your best to help the logs to be well consumed, without giving up with visible smoke in the home.

Dry wood, untreated, and temperate

A fire produces especially smoke in the first minutes after ignition, because the temperature is not yet high enough for combustion to go well. Here are several things to apply to avoid emitting too much PM10.

First of all, we will remember that it is forbidden to burn wood waste from construction sites or old furniture (painted wood, varnished, treated or soiled), because of the harmful smoke that emerges from it. We will therefore only use natural and very dry “tree wood”: wood which has not dried for at least one to two years will emit smoke. Before putting the logs in the hearth, we will take care to let them temper inside, because the cold wood burns less well. We will choose logs less than 10 cm in diameter, always to avoid poor combustion which is a source of smoke. And, finally, we will prepare your fire for thelight up over !

Start the fire without paper and from the top

It seems to go against common sense, but it is better light a fireplace from the top, In order to burn the logs like a candle – the flame on it. When you start the fire under large logs, as it is often the habit, we heat them without really consuming them: we only distill their wood which emits “condensates” (gas and particles), otherwise said substances that could burn but which escape unnecessarily in the chimney channel, since the flame is below them. On the contrary, when the fire starts from above, the condensates released cross the flame and burn by releasing their energy.

We prepare the fire by first having the big logs in the hearth, then we put over the small ignition wood: 3 to 4 logs of dry tree, covering a “fire lighter”-namely straw of wood mixed with wax or a mini -fagot dipped in the wax (see user manual -pdf 500Ko). Paper-day and cardboard are to be banished because they emit a lot of smoke. If we have applied all these principles well, the fire should emit little smoke to ignition, and more at all after a few minutes – but there remains an important source of pollution in PM10.

Regular sweeping

The regular sweeping of the chimney flue helps reduce the release of polluting substances, as well as the risk of fire (fire inside the duct) and intoxication to combustion gases. If the chimney tends to get crashed quickly after the sweater, it must be concluded that the combustion of the wood is hurt.

Particle filter for fireplace

To reduce the emissions of fine particles of its fireplace or its wood heating, the output of the smoke duct with an electrostatic filter can be equipped (60 to 95% PM10 reduction). The duct must be in stainless steel, because such a filter works with electricity (around 30 watts) and creates an electric field which attracts and fixes fine particles. It is cleaned annually, when the sweepur passes. Depending on the power of the wood heating and the place of residence, this filter can be compulsory for new installations (see. cantonal regulations).

Modernize the fireplace

It is said that an fireplace is “open household” when the fire burns freely before the eyes, with no other obstacle than a possible firewall, as is the case with many traditional chimneys. A chimney of this type is certainly very decorative, but it does not allow you to reach a high temperature, nor to adjust the air inputs well: it is particularly polluting and ineffective to heat a room, because the energy of the wood is only used in very low part (5% at best). In addition, a large quantity of housing air is sucked in by the home before being evacuated to the sky: between 300 and 500 m 3 per hour. During the heating period, a fireplace can therefore increase energy consumption, aspiring heated air and expeling it outside the accommodation. This hot air is replaced by cold air which creeps in the interstices of the windows and doors: sitting in front of the hearth, we have the feeling of having the cook face and the freeze that freezes.

We can modernize a fireplace, adding it to the ceramic doors. If they are tightly mounted and allow you to adjust the air inlet into the hearth, they reduce the air exhaust to around 50 m 3 per hour, and promote better combustion of wood.

We can do much better, by equipping the hearth with a “heating insert”, a kind of inner cast iron or steel fireplace, which allows both to adjust the amount of entering an incoming air and recover part of the heat. The ambient air is sucked, heated in contact with the insert, then redistributed in the room. There are many models, some of which with electric fan which can reach a yield of 50 to 60%.

The stove, champion of efficiency

The best option is to replace your fireplace with a Swedish stove, connected to the same evacuation duct that will ideally be “tuber”, that is to say equipping with an isolated stainless steel tube. The yield can then reach between 60 and 80%. If you prefer a “fireplace” look, there are efficient models (but more expensive than a Swedish stove): the “hot air fireplace” or the “accumulation fireplace” (about 75% yield). Even more expensive: the stoves with accumulation in ollar or ceramics. They heat a room less quickly, but their heat is released longer (yield up to 80%). There are also automatic wood pellet stoves, to load only every 2 or 3 days.

Fire without smoking • Explanation page with a video on www.Energy-Bois.ch

Modernize the fireplace, an interactive page of this site

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