
The Importance of Maintaining Your Chimney Liner
Creating a fire inside your house is nothing to take lightly. If you have a wood-burning fireplace, then you know that regular maintenance is key to keeping it in safe, working order.
While this of course applies to gas and propane fireplaces, it also applies to chimneys that are only used to vent furnaces and water heaters and not used for fires. One important aspect of fireplace maintenance is making sure that the liner of your chimney is in good condition.
A chimney liner protects your family from toxic fumes, as well as protecting the masonry of your chimney from the corrosive effects of smoke and combustion. Chimney replacement is one of the more expensive home repairs, but you can extend the life of your chimney by replacing your liner.
Sometimes liners and flues are thought to be the same thing and there is some overlap, but the term “flue” just refers to any vertical column that allows for gases to vent from your home to the outdoors. The gases that need to be exhausted through your flue are produced by fireplaces, furnaces, water heaters, boilers, or generators. Current law requires the flue to be lined, but older homes may not have had liners installed. The liner also serves to prevent fire from spreading to other structures in your home.
Over time, a liner can become damaged or deteriorate, and when that happens, it needs to be replaced. But how do you know when it’s time to replace your chimney liner? Here are a few things to look for:
Important Note:
Some masonry companies require annual inspections to honor their warranty, so read the fine print and follow their necessary safety and maintenance requirements to protect your investment.
Signs That It’s Time to Replace Your Chimney Liner
1. The Masonry of Your Chimney is Breaking Down
This is often first noticed when you have exterior bricks that are deteriorating. Bricks, stone, and mortar are quite porous, and combustion creates many corrosive byproducts that can eat away at them. In addition, many water heaters and furnaces vent through chimney flues, so condensation from their exhausts without proper liners can not only accelerate masonry deterioration, but can also create a dangerous situation for carbon monoxide to not be vented properly from your home.
2. Your Fireplace is Smokey
If you notice that your fireplace is starting to produce a lot of smoke, it could be a sign that your chimney liner needs to be replaced. When a liner deteriorates, it can cause drafting problems that result in increased smoke production.
3. There are Cracks or Gaps in the Liner
Have your liner inspected on a regular basis for cracks or gaps. If you see any, it’s definitely time to replace the liner. Even small cracks can allow dangerous gases and fumes to escape into your home.
Even if you don’t see any cracks or gaps, if the liner looks worn or damaged in any way, it’s best to err on the side of caution and replace it.
4. The Liner is Damaged or Missing
Some people may not even realize they don’t have a liner, especially if they haven’t had a professional chimney inspection. Many homes older than 1950 were not built with liners since they were not required until then.
The structures in your home that are adjacent to the chimney, such as framing, can ignite from the heat of the chimney and cause a house fire. Liners limit the amount of heat that transfers from the chimney to the adjacent structures of your home.
Be sure to have an annual chimney inspection before using your fireplace to keep it safe and functioning well.
5. You Have a Buildup of Condensation
This can cause damage to the structure of your home as well as generate more creosote from fires, which is a dangerous situation that can lead to carbon monoxide flowing back into your home. You will also have fires that are less effective in warming your home since they’ll produce less heat.
6. You’re Planning a Remodel or Converting Your Fireplace
If you’re planning any type of work on your fireplace, then it’s also a good idea to consult a masonry company about replacing the chimney liner at the same time. This will save you money in the long run by avoiding having to do the work twice, and will also ensure that you have the proper liner for your particular type of fireplace. Modernized fireplaces and stoves require specific flue sizes, and these usually need new metal chimney liners to go with them.
7. You Have Wildlife Getting into Your Chimney
This can be a sign of a deteriorating chimney or a lack of a properly installed chimney cap. A chimney cap protects your chimney from strong winds and rains, as well as animals.
Animals getting into a chimney can also be the cause of chimney damage from climbing and scratching the flue liner. Scratches create a place for creosote and soot to collect, and can result in holes in the liner.
Important Information About Federally Protected Chimney Swift Birds!
Chimney swifts are small birds with cigar shaped bodies that nest in chimneys. They are a federally protected species who used to nest primarily in hollow, old growth trees, but since those are few and far between now in many places, they have adapted to nest in chimneys. Professional chimney sweeps know swifts are protected species under the Migratory Bird Treaty Act.
When they nest in your chimney, you cannot have them removed, and it may take them ninety days or more to decide to move on their own. Once they leave, typically in the fall, it’s very important to have their nest removed and the chimney capped so they do not return to it the following year. They tend to return to the same place, so you’ll face the same issue annually if you do not take these steps.
It’s also important to always cap any chimney lined with a metal liner, as this can create a death trap for these birds and other animals since they cannot grip the smooth inside surface to escape if they fall inside the chimney.
There are steep fines and penalties for disturbing their nests or causing them harm.
Read more about protected migratory birds here:
Migratory Bird Treaty Act
https://www.fws.gov/law/migratory-bird-treaty-act-1918
What can you do if your chimney or liner are deteriorating and you can’t replace them?
If there is no risk of falling bricks or other safety concerns regarding the structure and you close off the fireplace, you could choose to install high efficiency equipment (water heater, furnace, etc), that do not need to vent through the chimney. Often these vent near the base of the house instead of through a chimney flue, and therefore do not create humidity that can further deteriorate your chimney masonry.
Hire a professional masonry company to advise you about capping off the chimney so they can make sure there’s nothing venting through the chimney that would cause a safety hazard.
If you choose to have your fireplace openings closed, a masonry company can do this with a sheet of metal that can be removed later when you’re ready to rebuild the chimney and replace the liner.
The masonry company may recommend removing the bricks all the way down close to the roofline in some cases if the chimney is at risk of falling over.
If your chimney is painted, this can also lead to masonry deterioration if moisture is sealed in. When having a chimney or any brick or stonework painted, it’s necessary to use a professional painter who is specifically familiar with how to properly prep and paint masonry.
On a personal note, we had to address a deteriorating chimney at a two story home built in the 1940s, and the chimney replacement price was going to be $25,000. We looked into our options, and decided instead of paying $25,000 to rebuild the chimney which was only being used to vent the water heater and furnace, we were able to purchase a new high efficiency water heater, a new high efficiency furnace, get the damaged bricks at the top of the chimney replaced, and cap off the chimney, all for $15,000 (in 2022). It wasn’t cheap, but it was a significant savings, especially since now we have new appliances also instead of just a new chimney. But everyone’s situation is different, so be sure to consult with experts for your particular situation.
Landlord Tip:
We require all properties with gas or oil-fired equipment to be monitored for carbon monoxide through a security company of our choice. This fee in our area in the Midwest is about thirty-dollars a month, and includes fire and security monitoring as well.
All the systems we install have a battery backup and are cellular based systems so that no landline is required. Battery backup is especially important, because if you have a power outage in the winter and your tenants use a fireplace to stay warm, you most definitely need to be monitoring for carbon monoxide.
At the very least, if you do not wish to have a monitored carbon monoxide and smoke detector to protect your tenants and property (which we recommend that you do!) then you MUST have working carbon monoxide detectors in the home that are placed appropriately, tested often and on a regular schedule by you and your tenants, and replaced as often as the manufacturer recommends.
We include an addendum to our lease that requires tenants to check the functionality of these monitoring devices monthly, to alert us immediately if there is any problem, and to never tamper with them or disable them.
When we used to have working gas fireplaces in our properties, we included in our leases that tenants must never fall asleep without turning off the fire, but that’s no guarantee they won’t. So we now have had all of the fireplaces closed off by a masonry company with a sheet of metal, because allowing tenants to have fires was just too big of a liability and risk to our investments. (If you chose to close off your fireplaces, you can request that the masonry company use black paint to spray the silver metal sheet they use to close them off, so that it still looks really nice and appeals to tenants as a decorative feature.)
Regular chimney maintenance is one of the most important safety items for your home.
Keep an eye out for signs like increased smoke production from your fireplace, cracks or gaps in the liner, or wear and tear on the surface of the liner. If you’re planning any type of work on your fireplace, such as relining the flue or replacing the damper, then it’s also a good idea to replace the chimney liner at the same time.
How long should liners last?
- 5 years for low quality liners
- 15-20 years for stainless steel liners
- 50 years for clay or cast-clay tile, or cast-in-place liners
- Lifetime Warranty for some high-quality stainless-steel liners may set you up with a lifetime warranty.
Clay Tiles
Clay tiles are the most common type of chimney liners, and are often found in older homes. They need to be maintained since they are pone to cracking. When properly maintained they can last for fifty years, but if they are cracked, they can lead to house fires and carbon monoxide poisoning. It’s extremely important to have them inspected regularly and before use of the chimney. Note that older clay tiles can be reconstructed with new clay tile liners or lined with metal.
Cast-in-Place Liners
Cast-in-place liners are made with a concrete type material that is poured into the chimney. They can withstand extremely high temperatures up to 2100 degrees, and therefore can reduce the risk of chimney fires. However, if they become damaged, the entire liner must be replaced. They also do not fit in all chimneys, so in those cases metal flue liners that can be flexible may be recommended. Some cast-in-lace liners can be combined with stainless steel liners also as an additional layer of protection and efficiency.
Metal Liners
Metal liners can be flexible or rigid, and can be insulated with specially designed wraps or jackets. Some experts argue that flexible metal liners reduce creosote buildup because they tend to flex more with temperature fluctuations and this loosens the accumulation, however this may not be the opinion of all experts, so consult a reputable professional who can help you assess the best option for your particular chimney.
IMPORTANT TIP AND PERSONAL EXPERIENCE:
Never try to use an unlicensed masonry company! This is one of those property maintenance items you don’t want to skimp on.
It’s easy to be persuaded by the cheapest price, but it may cost you a lot more in the long run in terms of damage to your property, liability, or personal safety.
Be sure to check that they are bonded and insured, have been in business a long time, and guarantee their work. There are not just a lot of unethical contractors out there, but also a lot of people who don’t have the proper skills or proper training for such a job.
Even if you check them out things can go wrong, so it’s good to be mentally prepared whenever you are going to tackle a big home improvement task. It’s not ever worth having a heart problem or stroke over, but these are unfortunately common occurrences for homeowners dealing with problem contractors.
We certainly are familiar with the stress it causes! In fact, we recently had a big problem with a masonry contractor who was highly recommended by several people we knew.
We needed to repair bricks at the top of a chimney for a rental property, and this contractor had all the right qualities on paper and references from mutual acquaintances. However, he evidently had some life problems that had caught up with him right around the time we hired him.
Unfortunately, he disappeared just a few days after taking our deposit and tearing down the top of the chimney – he also left his two story scaffolding and trailer in the yard! We learned that it’s illegal here to dispose of items such as this left by a contractor without following proper legal procedures, so we had to send a certified letter asking him to remove them and give him a thirty day notice to do so.
After a week of no contact from the contractor followed by a series of incomprehensible excuses, requests for more money upfront than agreed to in the contract, and finally an email saying he no longer had a truck to get to the job site, it seemed he had some very serious personal issues that he could no longer hide.
It was a stressful situation, but thankfully we were able to find another larger and more established company to clean up the mess and fix the chimney quickly. But we were not able to get our money back from the first contractor. We did not pursue the matter in court because it became clear that we would not be able to recover any money from him.
So even if you think you’re experienced in selecting contractors, this kind of nightmare can still happen. Don’t blame yourself, and don’t let it affect your health, just solve the problem as best you can and move forward. It’s very unfair, but you don’t want to have a physical confrontation with a contractor who’s unstable, or experience any detrimental health effects.
If you’re in the real estate investing business, the truth is you’re probably going to have some sort of big problem like this at some point. Try to be prepared with extra money put aside and the attitude that it will all be worth it, even if there are a few very stressful and expensive bumps along the way.
Conclusion
A chimney liner is an important part of your chimney that should be inspected annually by a professional company and kept it in good condition. Few people give it much thought over the years, but it’s a key item to keep your home safe and extend the longevity of your chimney. If you have just moved into a home, it’s important to have your chimney cleaned and inspected before use, and to set up a regular cleaning and inspection schedule.
With regular inspections, cleanings, and necessary maintenance, you can keep your fireplace safe and efficient and your heating systems venting properly for years to come!
Should you swap your fireplace for a ventless, gas firebox? Read more here.