How to Install a Chimney Liner and Save Money

Posted by Jeffrey Swerdan on Oct 18th 2023

How to Install a Chimney Liner and Save Money

This Article has been approved by our on-staff NFI Certified Specialists & Master Hearth Professionals

While cost is always a factor when considering a home improvement project, the most important thing, especially when dealing with your chimney and fireplace, is to have your chimney liner installed safely and professionally. If things are not installed correctly it could lead to a chimney fire and a chimney fire can cause property damage, home loss, and even personal injury or death. It is not worth the safety of your home and family to cut corners. With that being said, Northline Express has put together this article to help walk you through the basics of how to install a chimney liner. It will be your decision as a homeowner whether you feel comfortable tackling this project yourself or enlisting the help of a certified chimney sweep and installer.

It is our goal to help provide you with the information you need for a successful chimney liner installation.

Can I Install a chimney liner by myself or do I need to hire someone?

The installation process for installing a chimney liner is pretty straightforward. However, installing a chimney liner is a complex task that requires a b knowledge of how a chimney system functions. How a draft works and knowing what the state and local building codes and appliance clearance requirements are. As well as having a b understanding of what the best safety protocols are.

A chimney liner that is not properly installed can lead to major safety issues within the home and can lead to a chimney fire, property damage, and serious risks of personal injury or death. While it is possible that it can be a Do-It-Yourself project, it is recommended that a chimney liner installation only be performed by an experienced chimney professional or someone with the proper knowledge.

Check out this Chimney Liner DIY Installation Video

You can also check out the Northline Express YouTube Page for a helpful video called How to Install a New Chimney Liner Yourself. Our Northline Express YouTube Page also features a wide selection of product videos as well as a variety of videos about chimney liners and other products that we offer on our website.

The first step in the Chimney Liner Installation Process is the Assessment and Planning stage

The first step you will want to conduct is a thorough inspection of the existing chimney structure from the top of the chimney to the bottom of the chimney cavity where the appliance sits. You will want to assess the overall condition of the structure on the inside and outside of the cavity. This will ensure that there are no blockages or obstructions in the chimney flue. 

Then, you want to collect all of the measurements that you will need to order the proper chimney liner. The two most important measurements that you need to figure out are the diameter of the chimney liner and what length of your project that requires the new liner. The diameter is determined by two factors. The first is the appliance outlet and the second is the overall width and diameter of your chimney flue opening.

The next thing to keep in mind in the planning stage is what the overall configuration of your chimney system is. Is it just straight up from the bottom floor to the chimney crown or are there curves, turns, or bends in the chimney?

Lastly, you will want to ensure that you are in compliance with all state and local building codes and that you obtain any required permits for the job you are performing.

From the information that you gather, you will be able to determine the proper type and size of liner that you need and get it ordered. Many flexible liners can be ordered as a kit that includes a flexible liner, a tee, a top plate, and a cap.

Northline Express offers flexible aluminum, flexible stainless steel, and rigid chimney liner products in a variety of affordable options. You can check out our full line of Chimney Liner Options.

The second step when installing a chimney liner is to gather all of the required tools and materials that are needed for the installer

Here is a list of a few tools and materials that are most often needed for a chimney liner installation project:

  1. New Chimney Liner Kit: The flexible chimney liner components should be on hand. These components include the liner itself, tee and appliance connectors, and possibly insulation. The kit could also include a termination rain cap and the top plate that is installed over the liner above the roof.
  2. Installation Instructions: The first thing you want to review is the manufacturer's instructions. They are usually included with the liner kit, and will help provide guidance on the specific installation process all the way from the appliance connector up to attaching the liner to the top plate over the liner and more.
  3. Ladder: A stable ladder and/or scaffolding to access the roof and the top of the chimney.

  4. Tape Measure: To measure the chimney height and the required length of liner, as well as to ensure proper clearances. Also, measure prior to cutting anything.

  5. Chimney Brush and Rods: Used for cleaning the chimney before installing the liner to remove any debris or obstructions.

  6. Chimney Vacuum - To help clean up any mess that is made.
  7. Work Gloves: To protect your hands during installation and also when handling the liner and components

  8. Wrenches: For tightening clamps and connectors.

  9. Caulk Gun and High-Temperature Sealant: To seal connections and joints in the liner and between the liner and the termination cap.

  10. Screwdrivers: For securing connectors and termination caps.

  11. Tin Snips or a Saw: To cut the liner to the required length and trim insulation, if necessary.

  12. Vent Cap Installation Tool: If your termination cap requires a specific installation tool, make sure you have it on hand

  13. Flashlight: For inspecting the chimney and ensuring that the liner is properly aligned and connected.

  14. Safety Gear: Personal protective equipment, including safety glasses, a dust mask (when cleaning the chimney), and work boots.

  15. Chimney Inspection Camera: Optional, but useful for inspecting the interior of the chimney to ensure there are no hidden obstructions or damage.

  16. Fireproof Drop Cloth or Plastic Sheet: To protect the surrounding area in the home and on the roof from debris and sealant drips.

  17. Plumb Bob: To ensure the liner is properly centered and aligned within the chimney.

  18. Bucket and Cleaning Brushes: For cleaning and disposing of debris removed from the chimney.

Now that you have your chimney liner kit, insulation, and components, you are ready to move on to the next step in the chimney lining process

Now has come the time to prepare the work area and remove any obstructions.

  • Clear the Work Area - You will want to clear the area around the heating appliance and chimney. Be sure to remove everything from the mantle, as well as take down any fireplace doors, screens, or accessories and take them out of the area.
  • Protect the Work Area - Now, you will want to use drop cloths or protective plastic sheeting and lay it out all around where the work area is. This will help prevent damage to floors, walls, and the area and will also help contain the mess and make cleanup easier.
  • Remove Obstructions - This is the point where you will want to clear any obstructions or debris that is in the chimney cavity. This is also where you will want to make sure that there are no trees or obstructions above the roof to make it easier to have a clear path for the liner.

Now the time has come to install the liner and attach it to your fireplace, wood stove, furnace, or other appliance

The time has come to finally install the chimney liner itself. One of the brands that is highly recommended by the NFI-certified associates on our staff is the Lifetime Brand Chimney Liners.Below we have listed some of the install steps from their specific manual. If you are using a different brand of Chimney Liner, there may be a few differences in their installation process.

  • If you need to insulate the liner with rolled insulation, you will want to apply the insulation safely on the ground before moving forward with the installation.
  • The chimney liner tee will need to be installed and attached to the unit. So in some cases, you will need to remove a sufficient amount of brick and mortar to allow access for the installation of the tee’s snout at the base of the chimney where the heating appliance vent connector attaches to the tee of the lining system.
  • Separate the tee from its snout. Attach the tee to the liner with the fasteners provided.
  • Drop or pull the liner with the attached tee, without the snout, through the chimney until the tee rests in the base of the chimney where the brick and mortar were previously removed.
  • Attach the snout and place the end cap on the bottom of the tee with the fasteners provided. 
  • Attach the pipe connecting the heating appliance to the tee’s snout. Seal the area around the tee where the brick and mortar were removed with a furnace cement product.
  • Using a high-temperature silicone product, seal the joints where the snout of the tee connects to the pipes from the heating appliance.
  • Slide the top plate over the liner and place on the clay tile and center.
  • Mark the outline of the clay tile on the underside of the top plate.
  • Apply a wide bead of high-temperature silicone around the top surface of the clay tile.
  • Place the top plate over the liner and slide down onto the silicone. Hold in place firmly to create a good seal.
  • Screw the four fasteners provided through the 2" collar of the top plate and into the liner. Do not over-tighten the fasteners. 
  • Apply a bead of high-temperature silicone to the inside of the top section of the liner and to the lower section of the rain cap. 
  • Place the rain cap into the top section of the liner and push down until the stop bead of the rain cap meets the liner.
  • Remove excess silicone.

After the Install of the Chimney liner is complete, it is time to perform a draft test of the system

Now the time has come to test the system for Proper Draft. First, do a draft test to ensure that the chimney liner is functioning correctly before firing up the heating appliance.

A draft test is also sometimes called a draft analysis or draft measurement. It is a procedure used to assess the effectiveness of a chimney's draft, which is the upward flow of air through the chimney that carries combustion byproducts (such as smoke and gases) out of the home. This test helps determine if the chimney is providing sufficient draft for the safe and efficient operation of heating appliances like wood stoves, fireplaces, gas furnaces, and boilers. 

Draft tests are often performed by certified chimney professionals after the installation to make sure everything is sealed and working properly.

Before the initial firing of the appliance, make sure that you check the appliance’s operating instructions for initial firing precautions. 

After a successful draft test, the next step in the Chimney Liner Installation process would be to add Thermix to the Flue 

Thermix is a thermal ready-to-mix compound used as an insulation barrier for masonry chimneys and chimney liner kits. It is not required and is an optional accessory, but one that can help your overall system.

DuraVent presents Ther Mix, a ready-to-mix, vermiculite-based masonry material. Ther Mix cures into a lightweight, semi-hard compound that forms a thermal insulation barrier. This barrier works to keep flue gases warm and exterior chimney surface temperatures within safe limits. Additionally, Ther Mix acts as a masonry filler. When poured into the masonry chimney, Ther Mix fills the voids and cracks that could be found in the chimney walls. This eliminates airflow and moisture build-up between the liner and chimney. This helps increase efficiency in your system as well as provides a better draft for your chimney liner kit and heating appliance.

It is important to note: that using Ther Mix by itself does not replace the need for a chimney liner. It is also recommended to check with state and local building codes before installing to make sure that it is allowed for use in your area and for your specific project.

Now it's time for the Clean Up and Inspection phase of the installation process

The installation is complete and the system has been tested. Now it's time to clean up the work area. In this step, you will clean up the area around the heating appliance and on the roof. You will dispose of any debris and pack up all of your tools and equipment.

Then it is time to conduct a final inspection to ensure that all of the connections are secure and sealed properly. It is also the final check to make sure that you are compliant with all state and local codes.

Last but not least you will want to keep records of the installation. Here are some of the records that are advised to be kept in a safe place:

  • Receipts - It is a good idea to keep all receipts related to the purchase and installation. This includes your product receipts as well as copies of any installation bill of sales that you receive from installers, inspectors, or local officials
  • Product Manuals - It is a good idea to keep all of your product manuals for your appliances as well as all of the components for the chimney system
  • Permits - keep track and record all of the permits and documentation you need from state and local officials
  • Inspection Reports - copies of any notes or documents that you had to reference or sign your name to
  • Maintenance Records - a record of all inspections, cleanings, and repairs. This record can be valuable for future reference if an issue arises with the system or if you need to file a warranty claim. It can also help if you ever plan on selling your home.

As long as the system is maintained, a properly installed Chimney Liner can last a lifetime

Chimney liner systems are built to last and all that is required is creating and sticking to a regular maintenance schedule. Most fuel systems that burn oil and gas only need to be cleaned and inspected once a year. People tend to do this in the later part of summer or early part of fall before the cold weather starts to arrive in their area. This helps to ensure that their system is good to go for the winter months.

Wood burning and pellet burning systems burn a bit dirtier and can leave behind soot and ash that can accumulate and eventually lead to a buildup of creosote and if left untreated creosote has the potential to become extremely flammable. The more seasoned and dry your wood fuel is the less chance of creosote buildup.

If you only burn fires occasionally in your system then you may be alright with annual cleaning and maintenance. However, if you burn a lot of fires throughout the winter then you will want to clean the system at least twice a year, sometimes even three times a year if you end up burning wood with a higher moisture content. One schedule you could create is to do cleaning once before the winter, once halfway through winter, and once after the season has ended. The more frequently you clean, the less chance of creosote being allowed to accumulate and thus less chance that you could have a chimney fire.

During your routine maintenance checks, you will also want to check for and fix any cracks or damage in the chimney structure as well as check the termination cap for any signs of wear or damage, and clean and service your heating appliance at the same time. If your chimney liner is insulated, this is also a good time to make sure that the insulation is still intact as well.

It is also a good idea to keep a record of all inspections, cleanings, and repairs. This record can be valuable for future reference and also can help if you ever plan on selling your home.

FAQ - Installing a Chimney Liner

How much does it cost to install or reline a flexible chimney liner in a chimney flue?

The cost of installation varies greatly depending on the area that you are living in and the season in which you want it installed. It will also depend on the scope of work needed to complete the job and if any problems arise during the installation. On the low end, you could expect to pay anywhere between $1,000 to $3,000 for a simple install, whereas a more complex install could be up to $5,000 or more. While these can seem like significant amounts of money, it is an investment into the safety of your home and you will also be installing a system that is cost-effective and that has increased efficiency that can help you save money in the long run on heating bills.

How much does a new stainless steel chimney liner cost?

The average price range of stainless steel flexible chimney liners is between $20 and $40 per linear foot. The price will vary depending on the grade of stainless that you choose and the overall length and diameter of the liner that your project calls for. You can check out our full line of Chimney Liners to find the best option for your project.

How to line a traditional masonry fireplace and chimney for an open fire?

If you have a traditional stone or masonry fireplace and chimney structure, that you want to use to burn roaring wood fires, you can use a flexible chimney liner for this application as long as you adhere to your state and local building codes and purchase the correct style of chimney liner.

Can you install a chimney liner from the bottom up?

When installing a flexible chimney liner it is usually easier to install from the top down. The size of the flexible liner may make it difficult to feed it up the chimney. It can be done from the bottom up, but this will be more difficult.

Do I need to clean the chimney before installing the liner?

It is a great idea to have your chimney cleaned and inspected before installing a liner. If it is not cleaned prior there could be a buildup of creosote within the chimney that could potentially start a chimney fire. Although it is an added expense, it is well worth the money to prevent a fire inside of your chimney.

Where can I go to learn more about Chimney Liners?

Northline Express offers a Resource Center with helpful articles on a variety of topics. Here are some of the Chimney Liner articles that we offer:

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