Chimney Liner Insulation – Types, Process & Safety Issues

Here is a practical guide on chimney liner insulation.

One of the key functions of a chimney is to help vent combustion gases.

Sometimes, these gases lose their heat or cool down before they exit the chimney. This drop in temperature leads to increased creosote formation on walls of chimney liners thereby creating a problem.

Insulation For Chimney Liner

This is where chimney liner insulation comes into play as a measure to keep combustion gases hot. With such measure, there’s less condensation of these gases on chimney flue to form creosote deposits.

A greater part of our discussion will be centered on the chimney liner insulation.

You’ll discover why it’s important to have liner insulation installed and how it works. Also, understanding the cost and impacts of not having one will be necessary.

Is Chimney Liner Insulation Necessary?

With chimney liner insulation, the aim is to reduce the chance of condensation of combustion gases. When combustion gases travel up from the fireplace or stove, there’s a rapid drop in temperature.

This is mostly the case for chimney liners having no insulation.

• Chimney And Stove Pipe Insulation

With a drop in temperature comes condensation. The longer it takes combustion gas to exit the flue liner column, the more likely it is to lose its heat and condense on the liner.

This is a situation you want to avoid as such condensation forms creosote and soot.

With steady condensation, you’re faced with an increased buildup of creosote which might start a chimney fire when ignited. Creosote is highly flammable and could cause major problems when not cleaned.

Plus, the root cause contributing to its rapid accumulation must be resolved.

Simply having a chimney liner insulation installed could make a difference in the way your chimney functions. There’s a general improvement in the venting conditions of your chimney.

Insulated Chimney Liner Types

Although chimney liners perform the same functions, they come in different designs.

The two main types include the vermiculite insulation mix as well as insulation blankets. Each of these types of liner insulations is ideal for specific installation scenarios.

Let’s take a look at each type as follows.

i. Vermiculite Insulation Mix

There are situations where a flue is tightly fitted with little space left between the liner and the masonry chimney.

However, such spaces are sufficient enough to cause a drop in temperature for gases traveling up the chimney. The aim is to have such areas insulated.

Vermiculite insulation mix is the perfect solution for such a scenario. It consists of Portland cement and vermiculite and has to be mixed with water.

Once mixed into a paste, it’s poured around the chimney liner until there’s zero clearance.

This serves to insulate the stainless steel liner, thus conserving the heat from combustion gases. The result obtained is, better venting of gases and less condensation due to improved insulation.

• Safety Concerns about Vermiculite Insulation Mixes

As a mineral product that’s naturally occurring, vermiculite has been found to contain some form of asbestos. The majority of vermiculite compositions do. This raises a safety concern for users and homeowners.

Although it’s mixed with Portland cement, there are concerns that such may still be risky due to its asbestos content which is known to be a carcinogen.

You’ll need to be informed about this risk to enable you to take appropriate safety actions.

Speaking to your chimney expert might help. By discussing safety with your chimney technician, you’re able to have a better idea of how to act.

It’s important to also research widely on the impact risks of vermiculite insulation mix usage.

ii. Insulation Blankets

There are times when insulation blankets are preferred over vermiculite insulation mixes. This is due to ample spacing or clearance found between the stainless steel liner and the masonry chimney.

Insulation blankets are designed from high-density insulation material.

Like vermiculite insulation mixes, insulation blankets create zero clearance when installed. This is meant to provide maximum insulation.

Insulation blankets have the capacity to withstand high temperatures of about 2100 degrees F.

The Most Economical Way to Install Chimney Liner Insulation

There are lots of chimneys without liner insulation. Such chimneys hardly function optimally due to the high rate of combustion gas condensation on liners leading to creosote buildup.

For a homeowner seeking the most economical way to resolve the problem, there’s a way out.

A stainless steel liner can be insulated by wrapping it with insulation material before inserting it into the flue.

Insulation blankets come in handy for such types of jobs. However, you must seek expert help for such an insulation job.

There’s ever a possibility of not properly carrying out an insulation job correctly when DIY installation methods are adopted. A chimney expert is experienced in this area.

Such experience should be leveraged by calling for expert help.

Chimney Liner Insulation Works Both Ways

By now, you should have a fair idea of the benefits derived from insulating your chimney liner. Asides from those mentioned above, there are additional benefits such as the limiting of extreme heat resulting from a chimney fire.

This is most common with wood-burning applications with tend to accumulate creosote faster.

Although insulation significantly reduces the formation of creosote on chimney liner, it’s possible for previously (pre insulation) accumulated creosote to ignite when it’s not cleaned.

When creosote does ignite, liner insulation works to contain or restrict the fire from spreading. Extreme heat is kept from spreading through your chimney’s masonry structure and into your home.

Every homeowner will want to have such protection.

Will Chimney Liner Work Without Insulation?

While there are many benefits attached to chimney insulation, it’s also important to ask questions such as this.

What happens when a chimney liner isn’t insulated? For the most part, such chimneys will work without issues until when there’s a drop in temperature.

In winter, the importance of chimney liner insulation becomes clearer. With freezing weather, the possibility of combustion gases cooling before they exit the flue increases.

This creates all sorts of draft issues including the formation of creosote on liner walls.

The easiest way out is to make combustion gases retain their heat a bit longer until they exit the flue. This is only possible with chimney liner insulation.

All our focus so far has been on chimney liner insulation. We’ve looked at the benefits derived, the types of liner, as well as why it’s important to have one.

With this knowledge, you can go ahead to have your chimney liner insulated.