What Are Benefits of A Wood Burning Fireplace Insert?

A wood burning fireplace insert is a great way to reduce heat loss through a drafty old fireplace. If you are not familiar with wood inserts they are very similar to a wood stove but are designed to slide into an existing masonry fireplace.

Drafty Fireplace DemoIn addition to being very inefficient sources of heat standard masonry fireplaces can be a big source of heat loss even when you are not using them. Old or warped cast iron dampers rarely if ever offer an air tight seal. That combined with the strong updraft means your fireplace could literally be sucking heat right out of your house.

There are ways to control the amount of heat loss i.e. fireplace doors or a lock tight damper but neither of these improve the poor efficiency of your fireplace. If you want an efficient way to burn wood in your fireplace and effectively heat your home than you should definitely consider a wood burning insert.

The insert consists of two main parts the actual body of the stove and the surround panel. Because fireplaces come in so many different sizes manufacturers can’t make inserts to fit them all. Instead they include a surround panel that will cover any of the fireplace opening that the insert doesn’t fill. Some units have different style surround options available. Be sure you check to see what your choices are before you rule out an insert based on how it looks.

What Are The Differences Between Cast Iron and Steel?

Wood burning inserts come in a few different sizes, types and styles. Most fireplace insert manufacturers make small, medium and large models. A small insert is generally going to heat and are of under 1000 ft² a medium about 1500 ft² and a large 2000 ft² and above.

Cast Iron Fireplace Insert Steel Fireplace Insert
Steel Wood Burning Fireplace Insert Cast Iron Wood Burning Fireplace Insert

For how the insert is constructed there are two categories, steel and cast iron. Cast Iron units used to have a bigger advantage over steel due to their heat retention and durability. Modern steel stoves are much better constructed using superior metals than older versions. This has led to neither type of insert having a big advantage over the other although each does still have some small advantages.
Because of their heavier mass cast iron inserts tend to distribute their heat longer and more evenly. While steel inserts will heat up faster and in doing start heating the room quicker. Steel inserts are usually cheaper than the cast iron and will probably cost less to maintain.
Steel inserts have a firebox that is multiple pieces held together with a welded seam. Cast iron fireplace inserts are made up of multiple pieces or panels held together with high temperature gasket or cement sealing the seams. The cement and gasket materials will eventually break down and need to be replaced. This maintenance needs to be done to ensure the airtight operation of the insert. If any air is allowed to leak past these seams you will end up with a less efficient burn.

How To Properly Size Wood Burning Fireplace Inserts

One of the first steps to choosing the wood burning fireplace insert that is right for you is getting the correct size. The size of an insert is determined by two things:Wood Bunring Fireplace Insert Heat Circulation

  • The amount of space or square footage of the area you are trying to heat
  • The size of your fireplace opening

If your fireplace opening is big enough to fit a large insert than you can use the space your are trying to heat to help you determine the size. Here at the Chimney King of New England we generally advise people with a large fireplace to get a large insert. A large insert is going to have a bigger firebox and hold more wood. This means you will achieve longer burn times and have to reload the insert less often.
The other advantage to a large insert is in its visual appeal. The door and viewing glass are bigger which allows you to see more of the fire and let’s face it who doesn’t like the sight of a nice roaring fire.
Now if you are trying to heat a large space but have a relatively small fireplace you may want to consider doing a hearth mounted wood stove instead. By installing a wood stove in front of the fireplace you can probably get a unit that will heat larger area. There is no point in spending your money on a product that is not going to deliver the results you are looking for. This type of install can be tricky that is why it may be a good idea to have a professional wood stove installer like us come out to the house and assess what your available options are.
Use our conveniently provided »»fireplace dimension sheet«« to help you get the correct measurement for sizing your fireplace.

What Features Should I look for in A Wood Burning Fireplace Insert?

1. Blower Fans
Most of the fireplace inserts available today are going to include a blower fan as a standard accessory. Generally, these fans come with a variable speed switch that allows you to control how much heat is being distributed into the room.
One of the more common questions we here from people is “How loud is the blower?”. We understand, you want to make sure you will still be able to hear your TV or carry a conversation over the noise of the fan but this is usually not an issue. The fans on these fireplaces are pretty small and when run on a speed setting of medium or lower they are very quiet. In our experience we have found that the majority of the time people using wood inserts and stoves have the fans on a lower setting.
One of the most important things to do to keep your fan running quietly is keep it clean. The blowers inside most fireplaces use a long tubular fan blade called a squirrel cage. Dust will collect on them and cause them to spin out of balance. A fan spinning out of balance vibrates and this vibration is usually the noise people associate with the blower. By keeping it clean not only will you reduce any vibration you will also lengthen the life of the motor itself.
2. Catalytic Combustor or Secondary Air
These are the two names given to the different style systems used to ignite the exhaust gases inside your wood burning fireplace insert. Using one of the two systems is how wood inserts today burn so efficiently. We cover the differences between these two in more detail on our page for wood stoves but here are the main differences.
Wood Insert Catalytic Combustors
Catalytic Combustors: This is the more efficient of the two types but usually not by very much. Catalytic combustors have to be engaged and disengaged at the right times for an efficient fire. This means you will have to tend to the insert a little more. The catalytic elements themselves will eventually have to be replaced leading to additional costs and possible service calls. Taking proper care and only burning quality firewood will greatly affect the lifespan of the of these elements.
Wood Stove Secondary Burn Tubes
Secondary Air System: A secondary air system is a set of tubes that bring fresh air into the fire box to mix with the exhaust gases. Generally, less efficient (again not by much) than the catalytic type they are easier to operate. The secondary air is always being supplied to the fire which takes any of the guesswork out of it for you. Depending on the design there may eventually be parts like baffles that need to be replace. However, these components should outlast a catalytic combustor.
3. Enamel and Decorative Finishes
On some cast iron wood burning fireplace inserts you have the option to go with an enamel finish over the basic black cast iron. Obviously your personal taste should take precedence here but we generally advise people to stay away from the enamels.

Wood Insert Shown in Black Cast Iron Wood Insert Shown in Brown Enamel
Wood Insert Shown in Black Cast Iron Brown Enamel Wood Insert

Enamel finishes are beautiful but they can be chipped pretty easily. Since every wood burning appliance requires the use of tools like a poker or shovel it’s only a matter of time before you accidentally put a chip the finish. That along with the fact that enamel finishes usually add between $400 and $600 to the cost make in our opinion the black a better choice.
On steel inserts (and some cast iron) you might have the option to choose trims in different metal finishes. These are usually around the door or surround panel and are purely decorative. They will add to the cost so if budget is a concern you might have to the standard finish. Depending on the manufacturer and model you may be able to choose from polished brass (or gold), stainless steel, pewter, chrome, black chrome or brushed nickel.

What Do I Need For The Installation of A Wood Fireplace Insert

When you install a wood burning insert or a wood burning stove into a fireplace you need to connect the unit to the fireplace flue. There are two ways to do this with a direct connect (or partial liner) and a full stainless steel liner.
Installation Examples for Wood Burning Fireplace Inserts
Partial liners or direct connect installations are when you have a pipe or liner going from the unit past your fireplace damper and stopping where the flue starts. This type of installation used to be more common in the past but is not done very often now. A direct connect install is much going to be much harder to keep your chimney flue and the pipe clean in the future. In fact, almost every time we have to clean a direct connect system we have to remove the unit and the pipe entirely in order to do a thorough job. This is messier than a standard chimney cleaning and will cost you more money.
The other downside to doing a direct connect install is there is still a potential of losing heat though the chimney. When you only have a partial liner you have to install a block off plate where the liner passes through the damper. Rarely do these form an air tight seal so you will still be able to lose heat up the chimney flue.
The other type of installation is a full stainless steel liner. A full liner is going to go from the exhaust connection on the top of the appliance all the way to the top of the chimney where it is sealed down with a damper plate.
We strongly recommend connecting your new appliance with a full stainless steel liner for multiple reasons. First the smaller diameter of the stainless steel liner will heat up faster than the larger clay chimney. This will give you a better draft and the unit will run more efficiently.
Another reason to do a full liner is it will save you money when you have the chimney swept. When we sweep a full liner there is no reason to have to disconnect the stove. We simply run a brush from the top of the liner down and everything is collected in the firebox where it is easily and neatly cleaned out.
By doing a full liner you don’t have to worry about any cracks or damage in your existing liner. A chimney liner with cracked or broken flue tiles is a fire hazard. With a full liner installed you don’t’ have to worry about expensive chimney repairs in the future.
The last reason is with a full liner your chimney is now sealed at the top around the liner. By sealing it this way there will no longer be any draft sucking heat out of your house through the chimney.

How To Measure Your Fireplace For A Wood Insert

When Measuring your fireplace there are several other measurements to take into account other than the opening itself.

  • Flue It’s important to take into account the size and shape of your flue. Most inserts use a 6” diameter liner and this makes it tougher to fit down the flue. Also any significant bends in the flue may impede a liner from being installed. Some manufacturers have approved their fireplace inserts to be installed with a 5 ½” liner if the 6” will not fit.
  • Hearth For most fireplace inserts there is a U.S. code requirement that says you need a minimum 16” (18” in Canada) of non-combustible hearth in front of the door opening and some units require 18”. Taking into account that some of the fireplace inserts can project from the fireplace as anywhere from 0” for flush up to 14” or more you may need a very deep hearth to meet the required clearances.
  • Mantle Wood burning inserts all have clearances that have to be met for how closed the mantle can be. Pay close attention to these dimensions they could be the factor between your new insert passing inspection or not.


Once you have all your measurements take a minute and check out some of the different wood burning fireplace inserts that these manufacturers have to offer.

Majestic Wood Burning Fireplace Inserts Napoleon Wood Burning Fireplace Inserts Vermont Castings Wood Burning Fireplace Inserts