Chimney relining – What is it? Do I need it?

The Chimney Liner is an important part of the chimney which contains and channels the byproducts of combustion. Most chimneys are lined with terracotta flue tiles.  These are limited lifetime masonry products. For the liner to work effectively, it must be free of holes, cracks or damages of any kind. When the flue is ineffective, it allows moisture, creosote, smoke and/or carbon monoxide to enter the living spaces of the house.

Have your chimney inspected and cleaned as necessary on an annual basis. A certified chimney professional will make sure that the chimney liner is intact and is capable of performing its intended function of removing hot flue gasses from the home.


How a Chimney Liner Works

Chimney liners must have the following properties :

  •  Acid resistant – Flue gases are highly acidic and will eat away at loose mortar joints and seep into cracks , causing structural damage. Clay flue tiles are made to have some acid resistance but only for a limited amount of time.  Mortar joints connecting these tiles are rarely installed properly , rarely made of proper refractory mortar , and also have a limited life.
  • Properly sized for appliance – Chimney are built and sized to vent a particular appliance whether thats the furnace , fireplace or a wood or coal stove  Undersized chimneys won’t provide the capacity to draft the appliance. Oversize chimneys will allow the gasses to cool to quickly and not leave the home efficiently.  Flue tiles are installed with original construction in mind and its often the appliance or the home has been changed or improved over time,  rendering the system inefficient.
  • Gas tight – Leaks in a chimney could lead to potentially dangerous conditions as hot flue gasses escape into unintended areas.  But in addition , the performance of the venting of the appliance relies on the negative pressure of the chimney creating draft.  Cracks or holes or areas of missing mortar pull air from other areas of the home causing the chimney to draft less efficiently.  Its like sucking on a straw with a hole in it.  It’s not going to draft well.
  • Contain Heat – Surrounding your chimney is the wooden structure of the home.  When the inside of an unlined chimney is heated , a portion of that heat is transferred through the masonry structure to the surrounding combustibles.  The liner is made to prevent that from happening. Clay tiles are two inches thick and provide fair protection to prevent the typical hot flue gasses it vents from transferring heat through the chimney chase.  But if the chimney is unlined , or the existing liner is deteriorated or broken , a dangerous condition can result.

Why stainless steel liners ?

Because they meet and exceed the above qualifications necessary for safe venting.  They are gas tight as there are no seams  or areas for it to deteriorate.  It will be manufactured to be properly sized for the appliance it is venting .  It is acid and corrosive resistant  nor will it rust , and it is made to contain heat of combustion.

Clay tiles come in two foot rigid sections , attempting to remove and replace them is nearly impossible , short of tearing the entire structure down through the home.  A stainless steel pipe can be sent down the existing chimney structure to vent the appliance without such an invasive project being necessary.

Schedule your chimney liner inspection with Safeside Chimney

Regular inspection of a chimney to check for cracks in the coating bricks, mortar, or clay is necessary to ensure safe operation of the chimney system. If the inspection reveals damage to the inside of the chimney, the chimney liner must be repaired or a new one installed before the appliance connected to the flue is used again. Given the dangers to you and your family from using an old chimney that is unlined or  damaged, it is a good idea to investigate and use a chimney liner that creates a safe, durable and effective home heating system.

Call our office today. Our team would be glad to inspect your chimney and find cost-effective ways to keep your chimney in good shape and performing as it should!