Posted on: 29.08.2022 Posted by: Редакция Comments: 0

If your house features a fireplace, it is crucial that it is properly insulated when not in use. Fortunately, insulating a fireplace is not necessarily a complicated process and can be done using one of five methods.

Here is how you can insulate your fireplace when not in use:

  1. Close off your fireplace.
  2. Add a fireplace door.
  3. Seal the chimney.
  4. Try a fireplace blanket.
  5. Install a chimney damper.

Many of us think of fireplaces as a source of heat, and typically they are just that. However, even an unused fireplace that is not properly insulated can contribute to heat loss. The rest of this article will discuss how to properly insulate a fireplace when it is not in use.

1. Close off your fireplace

Fireplace plugs, also known as chimney pillows, act as a double barrier that prevents cold air from entering your home while retaining warm air inside. One of the most common brands of fireplace plugs is the chimney balloon.

Many homeowners choose fireplace plugs because they provide adequate insulation without making significant changes to the structure of the chimney. They can also be installed and uninstalled with minimal effort.

The fireplace plug comes in various sizes, so it must fit properly. Take the time to measure your chimney when making the selection, as an improper fit will not work well. Even with proper installation, small gaps may remain that can lead to air leaks.

There are different types of chimney plugs, and some may be better than others. For example, the inflatable chimney balloon blocker available on Amazon is manually inflated to fill the inside of the chimney, known as the chimney neck. Once inflated, the balloon should stay in place, creating a barrier both above and below the appliance.

Fireplace balloons and other fireplace plugs have some drawbacks. They are not long-term solutions. Over time, the balloon can deflate. It is best to reinflate every three months.

If the fireplace plug loses air, it can become loose enough to fall down. While it may occasionally land outside the house, the balloon typically falls into the fireplace box once it escapes through the chimney.

Fortunately, the chimney balloon is inexpensive and readily available in most areas. It can be purchased on Amazon and some hardware stores.

2. Add a fireplace door

Another excellent option for insulation is a fireplace door. When closed, they reduce heat loss by preventing drafts from entering the house through the chimney. The door acts as a barrier at the hearth of the fireplace.

Fireplace doors are made of glass. Additionally, several options are available. There are three main types of fireplace doors, described below:

  • Cabinet. Also known as double doors. They open like an average kitchen cabinet door, hence the name. They require clearance on both sides to fully open. They do not close as tightly as both types of bi-fold doors.
  • Bifold with tracks. Bifold doors open by folding in the middle. Bi-fold doors with tracks slide along a track along the door frame, resulting in some restriction.
  • Trackless bi-fold. Trackless folding doors not only fold in the middle, but can also be fully opened.

Polyurethane foam seals any gaps that may exist around the door, so it is commonly used for installing fireplace doors. Additionally, weatherstripping can be added if desired. Overall, fireplace doors and these materials provide excellent insulation.

Functionally, fireplace doors do more than just insulate your home when the fireplace is not in use. They are also an additional safety measure, specifically for wood-burning fireplaces, as they keep the embers inside the fireplace box.

3. Seal the chimney

Chimney caps are another method to insulate your chimney when not in use. However, the functions of chimney caps go beyond simply insulating your chimney. They not only keep out cold air but also keep out elements like rainwater. Additionally, chimney caps keep out any pests that occasionally enter chimneys.

Some of the most common animals found in chimneys are squirrels, raccoons, and bats. While they may only seem like a nuisance or inconvenience, they can actually take up residence and compromise the integrity of your chimney.

There are two types of chimney caps:

  • Spring-Loaded
  • Lock-top

Both are designed to fit with an airtight seal. Regardless of the type, chimney caps keep cold air out and help your home retain heat.

Like chimney pillows, a chimney cap must be properly attached. To create the airtight seal, you need the right size. Once properly installed, drafts are no longer a problem.

One advantage of chimney caps is that they can be used when your fireplace is in operation. They prevent gusts of wind from blowing ash, embers, and smoke into the house.

Chimney caps vary widely in price, depending on size and materials used. Additionally, installation costs $100 to $200. While some people attach their own chimney cap, most homeowners opt to hire a chimney professional.

4. Try a fireplace blanket

A fireplace blanket is very similar to a fireplace cover or door. It acts as a barrier at the hearth of the fireplace; however, they are recommended for masonry, wood-burning fireplaces.

Most importantly, fireplace blankets are fire-resistant. They are typically made of carbon fiber and easily attach to your metal grate using magnets. This simple design keeps cold air out and reduces heat loss through the chimney.

Fireplace blankets are easy to find and use. They are carried at many major retailers and hardware stores. When your fireplace is in use, the fireplace blanket can simply be folded up and stored away.

5. Install a chimney damper

A chimney damper is essentially a door in the chimney flue that controls the airflow. When closed, it prevents outside air from entering and indoor air from escaping through the chimney.

The chimney damper is opened and closed using a handle. There are three types of handles:

  • Pivot
  • Poker
  • Rotary

When the fireplace is not in use, the closed chimney damper provides insulation. However, when the fireplace is in operation, the chimney damper should always remain open.


Fireplaces can let unwanted outside air in. Fortunately, there are methods to prevent this. Hopefully, this article has provided some helpful advice on how to insulate your home when your fireplace is not in use.

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