When I build a fire in my upstairs fireplace, smoke comes out of my downstairs fireplace.
Q. I heat with gas. Should this chimney be checked too?
This is referred to as “ The Stack Effect “. This has become quite a common problem in modern air tight houses where weather-proofing has sealed up the usual air infiltration routes. The fireplace in use exhausts household air until a negative pressure situation exists. If the house is fairly tight, the simplest route for makeup air to enter the structure is often the unused fireplace chimney. As air is drawn down this unused flue, it picks up smoke that is exiting nearby from the fireplace in use and delivers the smoke to the living area. The best solution is to provide makeup air to the house so the negative pressure problem no longer exists, thus eliminating not only the smoke problem, but also the potential for carbon monoxide to be drawn back down the furnace/ hot water heater chimney. A secondary solution is to install a top mount damper on the fireplace that is used the least.
Without a doubt! Although natural gas is generally a clean burning fuel, the chimney can become non-functional from bird nests or other debris blocking the flue. Modern furnaces can also cause many problems with the average flues intended to vent the older generation of furnaces. Call us for a free assessment.
What should I know about Creosote?
A dirty chimney with only a quarter inch of soot contains the highly flammable substance called creosote. A hot fire around 1000 degrees F. could easily ignite this substance into a roaring chimney fire. At the height of a chimney fire, the creosote can burn at temperatures exceeding 2000 degrees F. Flames and flying embers can easily land on the roof and ignite the wood framing of your home. The intense heat can cause the flue to crack or collapse thus causing the interior walls of your house to burst into flames.
Creosote in chimneys comes in 3 stages.
Stage 1 is fine soot. It is easily brushed away leaving safe and clean flue walls.
Stage 2 is when it appears as hard, brittle deposits.
Stage 3 is glazed creosote in your chimney and is recognizable by its dense, shiny tar-like appearance. This unpleasant substance is basically wood tar which has become baked onto the walls of the chimney or flue lining. Once it is ignited in your chimney, it is extremely difficult to extinguish.
What causes glazed creosote to accumulate?
Unfortunately, there is no such thing as creosote-free wood burning. Creosote accumulation will occur no matter what kind of wood is burned and no matter what kind of wood burning system is used. What determines the type of creosote and its severity is how the fuel is burned. Solid fuel authorities agree that the amount of smoke, the temperature of the fire and the regulation of air (turbulence) are the major variables which determine the amount of build-up. A low burning fire, for example, will result in incomplete combustion, the number one cause of glazed creosote accumulation. An improperly installed fireplace insert, one that allows the smoke to cool too quickly in the firebox, is another situation which causes severe glazing. To combat this problem, flue gases should be kept between 250 degrees and 500 degrees F. if creosote accumulations are to be reduced in amounts of thickness. (Be sure to ask us about proven methods to assure correct burning.) If we have already diagnosed stage 3 creosote as a problem in your chimney, take our advice seriously. DO NOT continue to use your affected fireplace or wood stove. The simple fact is that a hot fire could easily ignite the glazed creosote and result in a dangerous chimney fire.
Can stage 3 creosote be removed?
Yes! There is now a product available to professional sweeps for removing glazed creosote. It's called TSR, or Third Stage Remover. Simply stated, this strong effective formula of fine cleaners dissolves baked-on resins from masonry, metal and stainless steel surfaces by reducing the hard glazed substance to loose, brushable soot. The TSR application will involve hard work by your chimney sweep, but the results will be worth the extra effort. After the product is applied, a drying time of 24 hours or more is required. As is often the case, several days may be necessary for complete drying to occur before brushing can begin.
Sometimes, the glazed creosote build-up is extremely think and difficult to completely remove in just one application. Therefore, the more severe instances of glazing can require two or three application of TSR for 90% to 100% removal. It is important to keep in mind that your professional sweep is able to suggest valid and honest corrective measures in making your home safe from chimney fires. Your family's safety and protection of your personal property are the professional sweep's primary concerns. To effectively remove hazardous glazed creosote from your home, take the time to discuss TSR with your sweep. Should you desire more information on glazed creosote and other possible fire hazards in your home contact your local fire department.
Why does my chimney need a rain-cap?
A chimney rain-cap keeps out the rain and animals. If this was the only reason for installing a rain-cap it would be enough. I have seldom seen an un-capped chimney over five years old that was not suffering from some kind of water damage. Go over to your fireplace right now and look at the back fire wall near the base. Take a screwdriver or coin and run it across the mortar between the bricks. Seem a little crumbly? Or maybe it's obvious by just looking at it. Typically, rain puddles up on the smoke shelf, mixes with creosote and turns into sulpheric acid, which seeps down and attacks the mortar joints in your fireplace. The mortar becomes weak and presto...the bricks become loose.
Besides that: Rain can set off a bad smell in the chimney. This will happen in warm weather, especially if the chimney is dirty or has animal droppings on the smoke shelf.
Keep out "unwanted guests" with a rain-cap
A rain-cap with wire mesh keeps out birds, squirrels and other "unwanted guests." Birds are fun to look at but they do have a few bad qualities when perched on your chimney. They chirp and flutter constantly, driving sane folks nuts and crazy folks bananas. Their droppings accumulate in a huge vulgar mass on the smoke shelf causing a bad smell, is a breeding ground for mites and bacteria. A squirrel can wreck a house faster than a dozen two-year-olds. Once they get inside the chimney the only way out for them is through the damper. Raccoons love to raise their young in the nice dark and warm smoke shelf, just a couple of feet from your living room. We have many styles of rain-caps. Ask us for more detials.
A rain-cap keeps out leaves/ twigs
Leaves/ twigs can choke a flue and set off a chimney fire in a dirty flue. The two main reasons for the breakdown of fireplaces and chimneys are heat and water. A chimney rain-cap takes care of the water damage, the "heat reflector/heat shield" takes care of the heat! In and unprotected fireplace, heat is absorbed into the back wall of the fireplace which causes the bricks to crack and the mortar that holds the chimney together to break down, leading to expensive repairs.
A fireplace with a Heat Reflector Shield protecting it. is now exposed to 1/3 less heat. The heat is radiated into the room where it should be and damage to the fireplace is significantly reduced or stopped! How much additional heat? 20% to 40% increases are being reported depending on the fireplace. Whatever the increase, it's always noticeable. You'll feel the difference.
FIRE-STARTING 101
What should I do in order to safely enjoy having a fire in my fireplace?
How often should I have my chimney swept?
Chimneys, fireplaces, and vents should be inspected at least once a year for soundness, freedom from deposits, and correct clearances. Cleaning, maintenance, and repairs shall be done if necessary. This is the national safety standard and is the correct way to approach the problem. It takes into account the fact that even if you don't use your chimney much, animals may build nests in the flue or there may be other types of deterioration that could make the chimney unsafe to use.
Factory-built fireplaces should be swept when any appreciable buildup occurs. The logic is that the deposit is quite acidic and can shorten the life of the fireplace.
My fireplace stinks, especially in the summer. What can I do?
The smell is due to creosote deposits in the chimney. This is a natural byproduct of wood-burning. The odor is usually worse in the summer when the humidity is high and the air conditioner is turned on. A chimney sweep will help but usually won't solve the problem completely. There are commercial chimney deodorants that work pretty well, and many people have good results with baking soda or even kitty litter set in the fireplace. The real problem is the air being drawn down the chimney, a symptom of overall pressure problems in the house. Some make-up air should be introduced somewhere else in the house. A tight sealing, top mounted damper will also reduce this air flow coming down the chimney.
Open the Damper
(This is forgotten more often than most people care to admit.)
Warm up the Flue
For fireplaces: Warm up the flue by holding a piece of burning rolled-up newspaper into the damper opening. Repeat this process a few times.
Start the Fire
Arrange two small to medium sized pieces of firewood on the grate, and place some crumpled up newspaper for tinder between logs. Now cover the tinder with several pieces of kindling.
Be generous with the kindling - it's the most important element in starting your fire. Now, place two more pieces of firewood on top of the kindling and two more at right angles to these two. Leave some space between the logs for air circulation. Light tinder. NOTE: Use only well-seasoned hardwood. If you have to burn softwoods, be certain they are well seasoned. Look for split, dry wood that has been stacked for up to a year. Loose bark and cracks in the
ends are signs of seasoned wood.
Close or position your spark screen(s)
Important do’s and dont's
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DO check the manufacturer's guidelines for your woodstove or insert.
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DO use seasoned hardwood.
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DO use commercial fire starters if you like.
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They eliminate the need for tinder and reduce the amount of kindling required.
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DON'T use charcoal lighter fluid or other flammable liquids. These are extremely dangerous. (Gel fire starters are okay.)
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DON'T burn artificial logs in a woodstove, unless they are specifically designed for woodstove use. Artificial logs can create soot deposits in the chimney much faster than regular wood and can be hazardous in certain situations.
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DON'T burn treated lumber, trash, or anything other than wood in your fireplace or woodstove.
Smoke spillage problems: Is your damper open?
If the chimney continues to spill smoke? Call us.
If it is and the smoking continues, open a nearby window a crack for a minute or two until the fire is going well - then you can close it again. If it just smokes when you light the fire, it may be because the flue is cold. Did you warm the flue with a burning rolled-up newspaper held in the damper region? (If not, that usually works.)
Efficient Burning Techniques
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The key is to burn small, hot fires, using hardwood that will minimize creosote accumulation and maximize heat output.
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Keep fires burning hot. Smoldering fires with a lot of smoke will cause creosote to accumulate quickly.
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Be careful not to add too much firewood. In a fireplace, keep the top of the flames visible below the fireplace opening. In a woodstove, keep the flames confined to the woodstove itself.
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For fireplaces with glass doors. Keep the doors wide open with the screen closed for a good half hour after starting the fire. When you see the fire is burning well, close the doors and set your draft controls to your preference.
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It's better to add smaller loads more often than to cram in a lot of wood trying to get an all-day burn.
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When you're ready to extinguish your fire. Separate the logs on the log grate. Close the screen or glass doors tightly, but don't close the damper until you're sure the fire and coals are completely extinguished and cool.
What to do if you have a chimney fire
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Get everyone out of the house.
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Call the fire department.
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Don't close the damper. If you have a fireplace with glass doors, close the doors and the vents. If you have a woodstove, close the doors and the air inlets.
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If flames are visible at the chimney top, hose down the roof, but not the chimney. Spraying water on a hot chimney will very likely damage it.
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Call us before using it again. Even a small chimney fire can damage the chimney, making it unsafe to use.
How to avoid chimney fires
Creosote is the main cause of chimney fires. A buildup of Creosote is highly combustible and can result in a chimney fire.
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Burn only seasoned wood
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Do not burn trash in a fireplace or woodstove.
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Don't allow the fire to smolder.
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Contact us to clean your chimney regularly.
