Replacing Flue Liners For Increased Chimney Draft Efficiency

Chimney draft is important when maintaining a fireplace and chimney. Chimney draft can be increased and efficiently maintained with a high quality flue liner.

A flue liner serves many different purposes. First, it protects your home from combustible gases seeping from the chimney into other rooms of the house. Next, a flue liner will protect the masonry work on the inside of the chimney from corrosive damage from the chemicals in smoke. Last, a flue liner can increase the chimney draft efficiency.

What Is Chimney Draft?

Chimney draft is the process of the hot air passing through the flue and out of the chimney. Chimney draft is necessary because it is the way that the hot and contaminated air from your burning fire escapes your home. Without chimney draft a fire in your fireplace is essentially burning in the middle of your house. The smoke won’t be pulled up a chimney but will simply fill the rooms. This would present a terrible problem. Chimneys are designed so that the hot, dirty air can be sucked from inside your home.

Chimney draft can be both increased and decreased by the conditions inside the chimney. If there are blockages present or if the structural integrity of the chimney is in question, the chimney draft is usually decreased. This means that the smoke is not being removed from the flue with enough efficiency. The suction or pull of the air is not great enough to overcome the resistance. A sound flue, with a smooth inside surface is the optimum environment to increase draft efficiency. When chimney draft is optimized, the smoke from a fire in your fireplace will be sucked into the flue and will expel through the opening in the top of the chimney.

How Can a Flue Liner Increase Chimney Draft Efficiency?

Replacing or installing a new flue liner is one of the best ways to increase chimney draft efficiency. A chimney is a masonry component. There are bricks that are laid on top of mortar. Over time, the seams between the bricks and mortar can begin to separate. When this happens, the chimney draft is compromised because the air can now expel at various places. 

Imagine a straw with a hole in it.  It is difficult to pull water through the straw. This is the case because the water can escape the straw before it reaches the top. Even when you maximize the force in which you attempt to pull the water from the straw, you aren’t going to get a full flow of water. This is exactly how your chimney works. If air is able to escape through cracks and small holes in the chimney, the draft will be slowed.

A flue liner stops this release of air and allows the air to pull itself from your chimney with increased efficiency. When a new flue liner is installed, it presents a defined path for the air to travel. There is no way for the air to escape the chimney and, therefore, it will pull with greater force and efficiency. Some flue liner systems also claim that they are able to repair any structural damage to the chimney. This is usually achieved when using a cast-in-place type of liner that uses poured concrete to line the flue from the inside.

A flue liner is essential to the efficient working of your fireplace and chimney.