Why are old chimneys crooked?
Usually it would be between where the chimney enters and exits the attic. Folklore says that this was done because witches could only fly down a straight chimney and the bend would prevent them from coming into your home. Another, more likely, reason for a witches crook has to do with home aesthetics.
Its purpose is to contain all the by-products from combustion, direct them to the outside atmosphere and protect the walls of the chimney from excessive heat and corrosion. Chimney flues are normally associated with a masonry fireplace.
The repair that is most used today for leaning chimney is helical piers. These piers are driven under the leaning chimney until it reaches a good soil base. Brackets are placed on the helical piers under the chimney footing. Then a hydraulic jack slowly lifts the chimney up to its proper position.
If a chimney has been correctly built and cared for, it can be expected to last for 50 to 100 years! But here's the thing, many chimneys have not been properly cared for throughout their lifetime, however. It is therefore essential to have your chimney inspected before you move into a new home and annually afterwards.
Bends in the chimney should be avoided, according to both the Building Regulations and British Standards, since a straight vertical chimney is much better at removing combustion gases. If bends are unavoidable, then there must be no more than four bends in the length of the chimney.
Heated gases in a chimney are lighter than the air in the atmosphere and are, therefore, drawn up into it. Logic suggests that a taller chimney produces more draft because of the simple fact that there tends to be more of this hotter, lighter gas in it, which creates more updraft.
The straighter the chimney the better it works and at least 80% of the chimney must be vertical. In a factory made system (twin wall flue) there can be a maximum of 4 bends with a 45 degree bend counting as one and a 90 degree bend counting as two.
A common and cheaper temporary fix that could have been done to hold the chimney in place is to fill the gap between the leaning chimney and main house structure with mortar or some type of caulking or expanding foam insulation. The chimney could also be fastened into place with metal straps.
Chimneys almost always have their own foundation and or footing. And usually, it's not built up to par with the rest of the foundation Just like there are specific signs and symptoms to look for in foundation settlement and foundation upheave.
Chimneys are among the heaviest and most structurally vulnerable of all exterior components of a building. Accidents caused by their collapse can lead to death. A collapse can also cause costly structural damage to the building and its surroundings.
How often should a chimney be relined?
Suffice to say, when you adhere to recommended chimney maintenance practices, your liner can last for 20 to 50 years. With this, it can be said that getting chimney relining services is not something that is done often.
A total or complete chimney rebuild includes replacing the outside brick as well as the crown. Total rebuilding is often recommended when you're dealing with extensive damage. Structural flaws, such as when a chimney is leaning or falling apart, usually require total rebuilds.
Clay tile liners and cast-in-place liners typically last around 50 years. Stainless steel flue liners generally last for 15 to 20 years (though low quality liners may not even last for five). Good quality stainless steel chimney liners often come with a lifetime warranty.
A fireplace chimney flue can be sloped, but it should only be done if absolutely necessary. The angle of the flue should be 90 degrees or directly perpendicular to ground level if possible. However, it is possible to come off of this vertical by as much as 30 degrees.
A wood stove pipe must be as short and straight as possible. At the least, 80% of it must be vertical. If it is so important, one or two 90˚ angles, at most, can be made part of the structure. The horizontal part should not rise more than a quarter from the linear foot.
In cases where our evidence shows that smoke or fumes is causing significant interference with another person's use and enjoyment of their property we can serve a legal notice on the person(s) responsible for the nuisance, requiring action to be taken to stop the problem or face prosecution for non compliance.
Water penetration can be a problem with masonry chimney materials. Chimneys are constantly exposed to severe weather, such as snow, heavy rain, or wind. These elements can cause the materials to deteriorate quickly and present the issue of cracks or moisture penetration.
They are covers for the top of the chimney, which is usually slanted. Rain can slide away from the chimney because of the tilt of the covers, which is a bargain compared to the cost of fixing one that's water-damaged.
Chimneys in ordinary dwellings were first built of wood and plaster or mud. Since then chimneys have traditionally been built of brick or stone, both in small and large buildings. Early chimneys were of simple brick construction. Later chimneys were constructed by placing the bricks around tile liners.
This is done to ensure the structural integrity of the chimney for years to come. While metal chimneys can be offset more, to ensure the chimney maintains a solid draw they cannot be offset more than half of their height.
Does a chimney need to be higher than the roof?
3-2-10 Rule Explained
Explained, the chimney pipe must be a minimum of three feet above the roof but also two feet taller than anything within ten feet. The portion of the rule stating the pipe needs to be 2 feet above anything within 10 feet is where most people get confused.
Because air pressure is lower at higher altitudes, and a taller column of rising air pulls harder on the air below it, increasing the height of a chimney generally strengthens draft. Traditionally constructed homes typically have at least 15 feet of vertical height between the firebox and the chimney opening.
Worn Mortar
Chimney masonry can last 100 years or more, but the mortar that holds bricks together expires after 25 years at best.
All in all, a well built chimney should last decades and if you keep up on the maintenance along the way you could have your chimney for 50+ years!
These flues are often found in the walls between the kitchen and the dining room in homes from the 1800s up to about 1930. In these houses, cooking was often done on one side and heating (with a coal burner or gas heater) done on the other, with both components plugged into a double-barreled brick chimney stack.
A strong, well-poured footer at least 12 inches thick is necessary for maintained chimney support for most chimneys. Larger, heavier chimneys require thicker footers.
A full masonry fireplace and chimney on a two-story house can weigh around 30,000 pounds. Recall that this weight is concentrated on a very small concrete footing.
Typically, under a chimney a foundation will be 12 to 24 inches thick, versus four inches for most foundations. In addition, the thickened portion of a foundation under a chimney (the pad) is often connected to two- to four-grade beams. Grade beams are like buried walls that are part of your foundation.
However, many older chimneys do not have liners. Without a liner, there is a higher chance of carbon monoxide and dangerous fumes leaking into the home. There is also a higher chance of serious problems with creosote build-up that can lead to fires.
How often should repointing be done? Once your chimney has been repointed correctly, it shouldn't need further repointing for at least 30 years.
How do you know if your chimney is safe to use?
- There's no bird nest or debris buildup on the cap.
- There are no tree limbs above or near the chimney.
- The mortar and bricks on the chimney aren't crumbling or missing.
- The chimney rises at least 2 feet above where it exits the roof.
How to Re-Line a Chimney Flue | This Old House - YouTube
The average cost to have a chimney lined by a professional is going to be about $2500. Depending on the type of chimney liner, it could cost up to $10,000. The average DIY chimney liner installation is going to cost about $750 and could cost as high as $3000 for the material.
Yes it can - and will! While having your chimney liner professionally installed can be more convenient but ends up being costly, averaging anywhere from $2,500 to $5,000. With our DIY Chimney Liner Kits you will have all the components needed to reline your chimney and you wont break the bank!
A complete chimney rebuild costs $1,000 to $3,500 to rebrick the stack above the roofline. A partial rebuild costs $600 to $1,000 to redo a small chimney or the top few feet of a large stack. A complete chimney replacement costs $4,000 to $15,000 to rebuild above and below the roofline.
- Failing Mortar Joints. This is a very important issue that needs to be addressed immediately. ...
- Spalling. Another moisture issue, spalling is when you end up with water getting into the stone or brick of the chimney. ...
- Rust. ...
- Ruined Walls. ...
- Discolouration. ...
- Shaling. ...
- Cracks in the Chimney Crown.
What is Repointing? When a masonry wall or chimney develops damaged joints, allowing moisture entry, it is recommended to remove the damaged portions and replace them with proper materials. This repair is known as “repointing”.
Softwoods like fir, pine and cedar make more smoke, and therefore more creosote.
Creosote buildup increases when the air supply is restricted in the chimney, unseasoned wood is used to make a fire, and when the chimney temperature is cooler than normal. Too much creosote buildup can cause chimney fires and these low burning fires can go undetected until they spread.
One method to loosen crusty or tarry creosote so it flakes off and falls down into the firebox or fireplace is to burn aluminum cans in a very hot fire. While this method works, it does not clean the chimney of creosote completely, and chimney brush cleaning is still necessary.
Why do chimneys lean in attics?
The causes of masonry chimneys leaning are that they weigh many tons, and that weight is concentrated on a small area. That is why it is important that a chimney be built on a concrete footing. A chimney may be attached to your home for stability, but that's not what's holding it up.
Our #1 tip is to crack a window on the same level (or below) as the fireplace — basem*nt windows work best. When you open the window, make sure that you feel the cold air blowing in.
Chimney Height Rules
A chimney that's too tall can result in the heated air cooling off by the time it reaches the top of the chimney stack. This can create a negative pressure inside of the smokestack that pushes smoke and other gases back into the home.
If you plan to use an existing chimney, both its location and the length of its flue will be determining factors. Note these guidelines: The horizontal section of the uninsulated stove pipe should not be more than three-quarters as long as that section of the flue above the point at which the pipe and the flue connect.
If you currently burn coal, you should consider switching to an alternative fuel, such as manufactured solid fuels known as briquettes for use on open fires and for stove users you could use smokeless coal known as anthracite or consider manufactured solid fuels but make sure the fuel used is suitable for your ...
There's one thing you shouldn't do, and that's burn them. Fence panels have generally been treated to help them last longer, so if you burn them, chances are you'll be sending lots of noxious chemicals into the air – a great way of making yourself very unpopular with the neighbours.
Cardboard
In a similar fashion to chipboard and plywood, cardboard is treated with an array of chemicals and resins. Even though it burns relatively well it should be avoided at all costs when looking to fuel your stove.
Long chimneys take the harmful smoke and gases produced in the factories high up in the air so as to reduce its harmful effects on the ground.
The tall chimneys were first created in the 1800's to catch high winds and spread to a greater and farther area so it is not just in one concentrated area.
These minimum chimney heights are specified to assure adequate draft necessary for safe heater operation and are separate from and additions to the fire-safety clearance distances discussed on this page.
How does air flow through a chimney?
Air rises through the chimney when the pressure in the fireplace exceeds the pressure outside. When there's no fire, or the fire is cool, the opposite condition may exist; the pressure outside may be greater than that inside. When that happens, air flows down through the chimney, making it difficult to start a fire.
