Cart 0


Frequently Asked Questions

Also be sure to checkout our Chimney Troubleshooting Guide


Why would you install a stainless steel chimney liner?

The chimney liner will protect your flue from the transfer of heat in your system to combustibles. It is also considerably less expensive than replacing your chimney. If your chimney is in need of repair from damage caused by corrosive gases eating away at the masonry and mortar, a stainless steel chimney liner is your least expensive and safe solution.

How much does it cost to reline a chimney?

If you do the job yourself, you would only incur the cost of the chimney liner and any related materials. It should take you anywhere from 2 to 4 hours to complete the job. The average costs to have a professional chimney sweep reline your chimney ranges from between $1500 to $3000 per job.

What damage can creosote cause?

Burning wood and fossil fuels at low temperature causes incomplete combustion of the oils in the wood, which are released as volatiles in the smoke. As the smoke rises through the chimney it cools, causing water, carbon and volatiles to condense on the interior surfaces of the chimney flue. This leaves a black oily residue referred to as "creosote”. Over the course of a season creosote deposits can become several inches thick. This creates a compounding problem, because the creosote deposits reduce the draft (airflow through the chimney) which increases the probability that the wood fire is not getting enough air to burn at high temperature.
Since creosote is highly combustible, a thick accumulation creates a fire hazard. If a hot fire is built in the stove or fireplace, and the air control left wide open, this may allow hot oxygen into the chimney where it comes in contact with the creosote which then ignites - causing a chimney fire.

Will insulating my liner help cut down on creosote buildup?

YES! When you burn wood and fossil fuels, the moisture in the wood mixes with the creosote that is formed from burning wood and rises in the chimney as a gas. When it cools going up the chimney it turns to a solid. The cooler the chimney usually towards the top of the flue the more you will find build up. An insulation kit installed on the liner will keep the stainless steel chimney liner warm all the way to the top of the chimney thus reducing the risk of creosote buildup. 

When installing a liner how do I get past the damper?

The best method would be to remove the damper by cutting it away although this is not always what the homeowner would prefer. You can also go from a round liner to an oval liner using an adaptor and then back to a round liner to connect to the stove or you can oval the round liner yourself to get through the damper and then bring it back to round to make the connection. The latter two choices are not the recommended method (but widely used) as cleaning that area could be tricky so if you do go with one of those choices be sure to thoroughly clean in this area to prevent any creosote buildup. 

Can I install a chimney liner myself?

Absolutely!!  With the help from the knowledgeable staff at Cheap Chimney Supply we will be there for you to answer your questions till the job is complete. If you are handy around the house then you will have no problem relining your chimney. If you are not sure what you need to do the job, call us.

What do I need to know to reline my chimney?

You will need to know the inside dimension of the flue you want to line, the length of the run from 8” above the chimney to the top of the appliance you are connecting to or the thimble or hole in the wall you want to go through. You will also need to know the outside measurement of the clay tile or masonry chimney to get the proper fitting top plate. The diameter of the liner in most cases is dictated by the inside measurement of the appliance you are hooking up to. Still unsure? Give us a call.

What does “Forever” really mean in your “Forever Warranty”?

Our Forever Warranty means exactly what it says, it has no time limit. This warranty is the best in the business because it is transferable to the next homeowner. A “lifetime warranty”, commonly used by other suppliers, varies in meaning from state to state and comes with a lot of small print. Our Forever Warranty is clear and to the point. No other warranty even comes close.



  • What is the CSIA?
    CSIA stands for the Chimney Safety Institute of America. It is a non-profit educational organization that provides chimney and venting safety resources to those in the industry and to you, the homeowner. Their goal is to educate all of us on how to eliminate chimney fires, prevent carbon monoxide poisoning, and improve the heating efficiency of our homes. The CSIA provides the only recognized Nationally Certified Exam and is responsible for the National Chimney Sweep Training School. It teaches sweeping and inspection of different chimney systems, operation of the necessary equipment, health and safety considerations and much more. It is a step-by-step, hands-on instruction of the codes, clearances, standards and practices of the chimney service trade.

  • What is NCSG?
    NCSG stands for National Chimney Sweep Guild. It is a national organization of chimney professionals that have come together to promote professionalism in the chimney industry & public awareness of chimney safety issues. NCSG works closely with the other organizations and stongly supports the codes and standards affecting chimney and fireplaces. It also works with the building and service trades, insurance and inspection officials, and others in the hearth industry to promote safe home heating.

  • What is the NFPA?
    NFPA stands for National Fire Protection Association. It is an international non-profit membership organization, founded in 1896 with more than 81,000 members. It is the world's leading advocate of fire prevention and an authoritative source on public safety. It is responsible for developing the codes and standards, continuing research, training, and education.

  • What is a UL listing?
    UL stands for Underwriters Laboratory. It is responsible for setting safety standards and testing for a wide range of industries and appliances. If an appliance or device has a UL listing, it means it has been tested to UL standards as they apply to a particular industry or application and it has passed. The tests are very strict assuring that only safe and reliable products receive the UL listing. A UL listing informs the consumer that the product he/she is buying has been suitably tested and found acceptable for the application for which it was intended. All of our Forever Flex and Ventis Lining systems are UL Listed and Tested.


    The INTERIOR of your CHIMNEY

    How can I prevent a “chimney fire” in my chimney?
    Have your chimney inspected and cleaned at least once a year. When building a fire, use dry wood and never burn cardboard boxes, wrapping paper, or trash. These items can spark a fire in your venting system. Build smaller, hotter fires that will burn more completely and produce less smoke. Attaching a stove thermometer to your stovepipe or stove door can help you monitor the temperature of your flue.

    How do I know if my chimney needs to be cleaned?
    If you see any of the following, it is time to have your chimney cleaned. There is soot dripping into your fireplace, signs of tar build-up, a strong odor coming from your fireplace or stove, reduced draft causing smoke to back up into your home, a critter has made a home in your system, or you just purchased your home and the previous owners could not tell you when it was last serviced.

    How often do I need my chimney swept?
    All working systems should be inspected and cleaned at least once a year no matter what they are venting. Systems venting wood burning appliances or stoves need to be cleaned more frequently as they create a greater creosote build-up.

    What is the purpose of a Chimney Liner?
    Most masonry chimneys are made of brick or cement block on the exterior, then have another liner on the inside. The purpose of this inner liner is to keep the heat of flue gases inside the chimney, so not to overheat the nearby combustibles, such as the framing and walls of your home, and possibly cause a fire. The liner is also crucial for keeping carbon monoxide, moisture, smoke, creosote, and other products of combustion from seeping through the bricks and mortar of your chimney and leaking into your home.

    Do all chimneys have liners?
    No. Some chimneys built before 1940 most likely were not built with inner liners. They were brick, stone, or cement block with nothing else inside. Chimneys constructed after that, were most likely built with an inner liner of clay flue tiles. The tiles, approximately 2-3 feet in length, are stacked and sealed together with mortar. This is indeed safer than no liner, but be aware that over time, the mortar joints between the tiles can break down or the tiles can crack. If this sounds like your chimney, it may be time to have your chimney lined or re-lined. Our Forever Flex and Ventis stainless steel liner is a great solution for your home that comes with a Lifetime Warranty. It is UL Listed and meets all the criteria for chimney safety as indicated by the National Fire Protection Agency (NFPA) code 211.

    If my chimney has clay tiles, can’t I just replace the original clay flue tiles?
    Yes, you can, however our stainless steel liners come with a LIFETIME WARRANTY and if installed correctly should never have to be replaced. Clay flue tiles will most likely crack again creating a recurring safety issue in your home.

    What should I do before installing my chimney with a new liner?
    First, make sure your chimney has been thoroughly inspected and any repairs needed, such as repairing loose or missing mortar joints between the tiles, replace any cracked tiles or missing bricks, and close any unused holes in your system, have been completed. Next, your chimney should be clean and free of all creosote, debris or other obstructions.

    Be knowledgeable of the codes, such as NFPA 211, that requires your chimney to be a minimum of 3 feet high from where it passes through your roof and meets the 10:2 ratio where your chimney is at least 2 feet higher than any part of the roof within 10 feet measured horizontally.

    Make sure there is only one coal or wood burning appliance connected to a single chimney flue. Wood burning appliances should NOT be connected to any flue venting a gas fired appliance.

    What is the difference between a Forever Flex flexible lining system or a Ventis lining system, and Which one should I use?
    Forever Flex is a flexible one piece liner that can be maneuvered easily through offsets in the chimney. The Ventis system consists of sections (12”, 18”, 24”, 36”, 48”) of rigid pipe that are attached together with rivets. Each chimney is unique, if the inside of your chimney has offsets (or turns), a flexible liner will be easier to install. However, if your chimney is short and strait (12 feet or under), a rigid lining system would be an option.

    My fireplace smokes a lot on the inside and when I am not using it my house smells. What can I do?
    To eliminate the smell, a product called Fireplace Deodorant can help! There could be several reasons why the smoke is not drafting properly out your chimney flue, so it is always a good idea to have your chimney inspected and/or cleaned for any serious issues. It may be a simple solution like installing a Smokeguard on the front of the fireplace if the opening is too large. For more helpful tips consult the Chimney Trouble Shooting Guide.

    The EXTERIOR of your CHIMNEY

    If the crown on the top of my chimney is starting to crack and deteriorate what can I use to repair it?
    If the mortar crown is loose, crumbling or severely deteriorated, it should be replaced with a new cast-in place concrete crown. However, if the crown is damaged but structurally sound, larger cracks and voids can be filled with a patching cement or high quality caulk then covered with Crown Coat.

    What can I use to repair the minor cracks on my brick chimney?
    Crack Magic is a highly durable silicone elastomer (think of it as a paintable caulk) that is perfect for repairing cracks up to 1/8" wide. It's easily applied with a brush and dries in about 6 hours to a milky white film that will not significantly change your chimney's appearance!

    What is the white substance on the outside of my chimney?
    This is known as efflorescence. It is the product of an un-lined chimney or a clay lined chimney with cracks and or missing mortar joints between the tiles allowing acidic condensation and moisture to bleed through the masonry structure causing it to turn “white”. A Forever Flex liner will create a sealed system containing the acidic condensate and preventing this from happening in the future! One solution to remove the white stains from your chimney is with Brick & Mortar Cleaner.

    The TOP of your CHIMNEY

    I have rain coming down the inside of my fireplace. What can I do?
    You may want to install a chimney cap or top sealing damper to the top of your chimney that will prevent water from entering into your lining system. If you currently have one, you may want to inspect the “crown” of your chimney for any cracks or other needed repair.

    There are bats in my fireplace! Please help?!
    You need to enclose or close off your chimney when it is not in use, so bats or other critters don’t make it their new home. A top sealing damper or stainless steel chimney cap is what you need!

    What is a chimney cap?
    A chimney cap attaches to the top of a chimney. It’s purpose is to protect the inside of the chimney, keep sparks and cinders in, and keeps critters out! Multi-Flue chimney caps cover more than one opening on the top of your chimney and are also important for protecting the “crown” or top of your chimney. This makes it less susceptible to the weather, therefore lasting longer.

    I know I need a cap that covers the two flues in my chimney. How do I know what size Multi- Flue Chimney Cap to get?
    You need to measure the outside perimeter of the top of your chimney and subtract 3" from each side. This will tell you what size screen you need. Next, measure the height of the highest protrusion or flue tile extending out of the chimney. The Height of the chimney cap should be a minimum of 6” from the highest protrusion, therefore you will need to add 6” to that number.

    For example, the outside of brick measures 23"x35" and the flue tile sticks up 4". You will need to subtract 3” per side, which you get 17”x29” and add 6” for the height requirement. The above chimney will need a 17"x29" Multi-Flue Cap with a 10" height.

    Our Products

    Can you make me a copper anaconda snake for my kid’s school project?

    Or can you make a stainless steel bird bath for my blue jays? Absolutely! Because of our extremely popular Custom Shop™ we have come to the rescue many times, in creating unique parts for specific jobs. The motto of our Custom Shop™ is “if you can dream it, we can build it”. So give us a challenge with the next custom part you may need. Yes, we can make it all, including the kitchen sink.

    Why do you carry so many different crown repair and sealant products?

    Simply put, Cheap Chimney believes in selection. Some of our vendors only want us to carry their brand, but we know you want a variety. We want you to make the choice.

    What is the largest diameter pipe you can manufacture?

    Our largest Flex Pipe is 16” round, we can also produce any shape you want. Our largest Rigid Pipe is 42” round. And because of our Custom Shop™ we can produce virtually any size square or rectangular rigid pipe you would need.

    When you rectangularize, squarize & ovalize is your liner still UL listed?

    The answer is yes! Incidentally, not all manufacturers can boast this achievement.

    Is it ok to cement around Forever Flex liner at the crown of the chimney?

    Yes it is and Forever Flex is UL Listed to do so. Chimney has invested much time and resources into this project. Why not check and see if the liner you use is UL Listed for this purpose?

    How flexible is your liner when it is ovalized, squarized, or rectangularized?

    This question has two answers depending on the type of flex liner used. No matter what brand you purchase, light flex will always lose flexibility when shaped. Heavy flex, depending on the shape, will sometimes increase or decrease in flexibility. One of the advantages our customers experience with shaped liner is how we ship it. In most cases, we don’t coil the liner; it is shipped straight which enables an easier installation. This also prevents the liner from corkscrewing when it’s uncoiled.

    Sizing Liners

    How do I get the appropriate liner size for a heating appliance?

    When you are sizing an oil appliance you need to obtain the max GPH (Gallons Per Hour) of the unit. Then using NFPA31’s slide chart, you determine the diameter of the pipe needed. (When GPH can not be obtained, generally 140,000 BTU’s will equal 1.0 GPH)

    When you are sizing a gas appliance you need to obtain the max input BTU (British Thermal Unit) of the unit. Then using NFPA54’s slide chart, you determine the diameter of the pipe needed.

    When you are sizing a wood or coal burning appliance, simply line the chimney using the same diameter as the flue collar size installed on the appliance.

    With oil appliance sizing, what if the GPH is higher than what’s on the chart?

    Unfortunately the sizing chart found in NFPA31 does not go beyond 6 inch diameter pipe. (This was due to lack of funding.) When the GPH is higher than what is on the chart, simple line the chimney using the same diameter as the flue collar size installed on the appliance. The only alternative to this is to get written direction from the manufacturer for sizing the liner to the appliance.

    How does Cheap Chimney help you size oil and gas appliances?

    We have made this job of sizing a chimney liner easy and simple for you. Obtain an oil and gas “slide sizing chart” and in a few seconds you can correctly size the appliance you’re working with.

    Technical Questions

    How often should a chimney be inspected?

    It is always encouraged to have it inspected at least once a year.

    How often should a chimney be cleaned?

    This depends on how much it is used. When a ¼ inch of creosote builds up on the chimney wall, it needs to be cleaned. On average most chimneys are cleaned annually or semiannually.

    Is your chimney liners UL listed for use after a chimney fire?

    Yes it is. When this liner was tested it was put through the worst chimney fire possible by use of an incinerator. After a temperature of 2100F degrees was reached for some time, then the liner was pulled out and tested for strength and durability. The composition of the stainless steel was also tested. When the liner was not affected by this high heat attack, it then received its UL 1777 Listing. This chimney liner was manufactured to handle and perform after a chimney fire.

    Can you insulate this lining system with pour-down insulation?

    Yes you can. We have our own pour-down insulation called, EverGuard Insulation Mix™. Our insulation is UL Listed to be used with our chimney liner family. It comes in 45 pound, 2.5 cubic foot bags.

    What would you use furnace/refractory cement for?

    You would use this for practically any high heat area you would need cement for. Use it for bedding and cementing firebrick and specially shaped combustion chambers. It is good to 3000F and it won’t shrink, pull away, crack, sag, or lose its sealing properties.

    All About Metals

    What does the “Ti” mean in 316Ti?

    TI means that titanium was added to the composition of the stainless steel.

    What is the difference between 316Ti and 316L stainless steel?

    A small percentage of titanium adds a lot of quality to your alloy. Titanium stabilizes the alloy at extremely high temperatures of 800 degrees and above, which can occur during a chimney fire. Titanium combines with carbon, preventing the precipitation of chromium carbide from the material. If this precipitation would occur it leaves the alloy grain boundaries chromium depleted and susceptible to intergranular attack (corrosion). The main advantage of 316Ti is that alloy can be held at higher temperatures longer before sensitization occurs than in a non-stabilized alloy like 316L.

    Why does Olympia Chimney use 316Ti rather than 316L?

    Even though this alloy has a little higher cost Olympia Chimney is dedicated to using the best metal available. We want the liner you install to be able to stand up to even the harshest conditions, especially during chimney fires. Since this is a better alloy hands down, does your supplier use 316Ti?

    What is AL29-4C alloy stainless steel?

    “AL” stands for Allegany Ludlum. This company invented and patented this unique alloy. This alloy was developed to prevent corrosion and breakdown in high efficiency gas and oil chimneys. AL29-4C offers extreme resistance to chloride ion pitting, crevice corrosion, chloride stress-corrosion cracking and general corrosion.

    When should I use AL29-4C?

    When there are heating appliances that are 83% or higher efficiency, it is a good idea to use AL29-4C. This provides better corrosion resistance to condensed flue acids that are formed.

    Does Cheap Chimney use metals that are seconds, overruns, or inferior?

    We know what people who ask this question are really thinking – “this is such a good price, something must be wrong”. Be assured that the steel used in the Forever Flex family of liners is from superior steel mills and processing centers. All our stainless is prime metal with certificates of analysis, available anytime for your assurance. This means we never use material that is seconds or low budget overruns. Our materials are prime all the way.

    What’s the difference between 304L and 316Ti stainless steel?

    All liner pipe is made of prime stainless steel. Depending on the application you could use 304L stainless is used for wood burning appliances and 316Ti stainless is for all fuels (wood, oil, gas, coal).

    Where is the stainless steel market heading?

    Because of the rising prices of stainless steel, many have wonder where is it heading, or why have the prices even climbed in the first place. This is a complicated issue that is not just experienced in the United States. Most analysts agree, because of the increase of China as an industrial nation, there is a great demand for stainless steel. Because of this great demand and a limited supply of molly and nickel, components that make up stainless steel, prices have sky-rocketed.

    What has Cheap Chimney done to keep our price of stainless steel products down?

    Each year, when our new catalog is published, we have held our prices throughout the whole year. Even though the cost of steel increases throughout the year, we hold to our catalog prices. Also, because of the high volume of steel we purchase, we are able to purchase steel at the lowest possible price.

    One message we want to make clear: We have not downgraded or gone to seconds or other cheaper sources to sacrifice quality of our stainless steel. Here at Cheap Chimney we only purchase prime stainless steel. A certificate on analysis comes with each coil and can be obtained when desired.