The 6 Best Gas Fireplace Inserts of 2021

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Best Gas Fireplace Inserts

The Spruce / Chloe Jeong

A gas fireplace insert provides heat and flames without producing the smoke, soot, and ashes associated with a wood-burning fireplace. Whether you’re looking to retrofit an existing fireplace or create a custom gas fireplace feature, these inserts offer a variety of installation and fuel options.

Before shopping for the best gas fireplace inserts for your home, it's helpful to learn the differences in venting types, as ventilation affects installation requirements. There are several options on the market, including natural vent, direct vent, and ventless gas fireplace inserts. Every variety needs fuel to operate (either natural gas or propane), and some models offer dual-fuel capability. Be sure to compare BTU output and heating efficiency to determine which inserts will meet the expectations for heating your space. 

Enjoy heat and flames on demand with one of these top gas fireplace inserts. 

Our Top Picks
Equipped to use propane or natural gas, this dual fuel insert offers fast, efficient heating using the included remote control.
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Pick this model if you want to go beyond basic black for your gas fireplace insert; it also comes in pewter and copper finishes.
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This model is a basic starting point for building the gas fireplace that fits your style and budget.
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Enjoy 20,000 BTU of heat from this model that can be vented horizontally or vertically.
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This B-vent fireplace insert only requires a 4-inch vertical exhaust pipe but supplies up to 21,000 BTU of heat.
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With eight realistic, hand-painted logs, this log set can warm a room up to 1,300 square feet and has an automatic shut-off feature.
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Best Overall: Duluth Forge FDF300R Vent Less Gas Fireplace Insert

 Duluth Forge Vent Free Dual Fuel Ventless Gas Fireplace Insert

Venting Type: Ventless | Fuel Type: Dual Fuel | Front Product Width: 29.1 inches | Material: Ceramic | Heat Output: 26,000 BTU/hour

What We Like
  • Includes remote control

  • Heats up to 1,350 square feet

  • Oxygen depletion sensor

What We Don't Like
  • Lacks a thermostat

Heat your room in a hurry with the help of the 26,000 BTU per hour Duluth Forge Vent Less Gas Fireplace Insert. This model is sized for heating spaces up to 1,350 square feet and requires no external venting. As a safety precaution, an oxygen depletion sensor (ODS) monitors air quality and will sound an alarm if oxygen levels become low.

You can slide the Duluth Forge Vent Less Gas Fireplace into your existing masonry fireplace (with appropriate ductwork) or build a fireplace to suit this insert exactly. Its remote control makes starting a fire as simple as pushing a button: Unlike a wood-burning fireplace, there are no matches or fire starters needed.

Best High-End: Kingsman Fireplaces IDV33 Direct Vent Fireplace Insert

Kingsman Fireplaces IDV33 Direct Vent Fireplace Insert

Venting Type: Direct Vent | Fuel Type: Natural Gas | Front Product Width: 34.5 inches | Material: Metal | Heat Output: 31,000 BTU/hour

What We Like
  • Blower with variable speed settings

  • Option for louvered or solid surround 

  • Equipped with safety screen barrier

What We Don't Like
  • Lacks dual fuel flexibility

  • More heat loss to flue than ventless models

Choose the features and options that matter the most to you with this high-end gas fireplace insert from Kingsman Fireplaces. With both natural gas and propane fuel options, you'll also get to decide whether to upgrade to IPI (immediate ignition) or standard millivolt ignition, which takes up to 30 seconds to light. As a direct vent model, this insert sends exhaust up your existing chimney with a chimney insert or horizontally through an exterior wall with special ductwork. 

While many gas fireplace inserts have a uniform appearance with a black metal surround and rustic-looking logs inside, this splurge-worthy option offers more choices. You can choose between a louvered or solid surround, a traditional log set, or contemporary crushed glass interior, and either black, pewter, or copper exterior finish. No matter which style you choose, the functional features of this gas fireplace insert make it a smart buy—a heat-activated blower with variable speed control distributes warm air into the room, a safety screen provides added protection, and a remote gives you quick control from anywhere in the room. 

Best Budget: Pleasant Hearth PHZC32F Vent Free Gas Firebox

Pleasant Hearth PHZC32F Vent Free Gas Firebox

Venting Type: Ventless | Fuel Type: Natural gas or propane | Front Product Width: 32.19 inches | Material: Metal | Heat Output: Not applicable

What We Like
  • Zero clearance insert

  • Includes draw screen for safety

What We Don't Like
  • Must buy a set of gas logs 

  • Decorative brick panel insert sold separately

Many gas fireplace inserts are sold as a complete package, including a log set with a burner or other filler material. However, another option to save money or customize the look of your gas fireplace is to purchase a gas firebox without logs. You can add the log set of your choice or other filler material (like crushed glass) and a burner.

For an affordable gas fireplace insert, choose the Pleasant Hearth Vent Free Gas Firebox, which is priced several hundred dollars cheaper than many other popular models. It offers zero-clearance installation options, a fire screen for safety, and it can be used with either natural gas or propane log sets. While you still need to purchase the log set to make this gas fireplace insert functional, you’ll be able to choose components that fit your style and budget. 

Best Direct-Vented: Empire Tahoe Deluxe Direct Vent Fireplace

Empire Tahoe Deluxe 36" Direct-Vent NG Millivolt Fireplace

Venting Type: Direct Vent | Fuel Type: Natural Gas | Front Product Width: 37 inches | Material: Metal | Heat Output: 20,000 BTU/hour

What We Like
  • Only 16 inches deep

  • Includes brick liner and logs

What We Don't Like
  • Not equipped for dual fuel

  • Barrier screen or door set sold separately

A direct-vented gas fireplace insert creates more versatile installation options since it can be vented horizontally or vertically. It also offers the advantage of using the outdoor air for combustion, rather than drawing in warm air from the room you'd like to heat. 

The Empire Tahoe Deluxe NG Millivolt Fireplace provides up to 20,000 BTU of heat using a natural gas supply. It features a brick liner and six ceramic logs for an authentic fireplace look. The glass front provides a sealed chamber for combustion, but take note that the glass can become very hot to the touch. You’ll need to buy a barrier screen or door set for protection against touching the hot glass. This fireplace insert measures 37 inches wide but only 16 inches deep, allowing it to fit into shallow fireplace openings. 

Best Natural-Vented: Empire Comfort Systems Deluxe Keystone Series B-Vent Fireplace

Empire Comfort Systems Deluxe

Venting Type: Natural vent | Fuel Type: Natural gas | Front Product Width: 37 inches

Material: Metal | Heat Output: 21,000 BTU/hour

What We Like
  • 4-inch exhaust vent

  • Log set included

What We Don't Like
  • Blower is a separate accessory

Natural-vented gas fireplaces vent vertically, like the chimney on a standard fireplace. Also sometimes referred to as a B-vent fireplace, this type of gas fireplace insert pulls air from inside the room while exhausting it up and out of a chimney outfitted with the proper ductwork. The result brings large, bright flames that more closely resemble a wood-burning fire than direct vent or vent-free models of fireplace inserts. 

The Empire Keystone Deluxe B-Vent Fireplace measures 37 inches wide, while the B-vent is just four inches in diameter. This fireplace includes a brick-look liner and a set of logs for a cozy ambiance all year long. It has an output of 21,000 BTU using a natural gas supply. Generally speaking, natural-vented gas fireplace inserts are ideal for heating smaller rooms. They provide warmth while exhausting fumes, but won’t overpower a room with too much heat like some direct vent models.

Best Log Set: Duluth Forge Ventless Dual Fuel Log Set-24 in 33,000 BTU

 Duluth Forge Ventless Dual Fuel Set-24 in

Venting Type: Ventless | Fuel Type: Natural Gas or propane | Front Product Width: 18, 24, or 30 inches | Material: Refractory ceramics | Heat Output: 33,000 BTU/hour

What We Like
  • Realistic shape and texture

  • Automatic shut-off

  • Battery Assisted Piezo ignition

What We Don't Like
  • No remote

A gas log set can be used along with a fireplace insert or inside an existing wood-burning fireplace. The Duluth Forge Ventless Dual Fuel Log Set can use natural gas or liquid propane, offers eight realistic, hand-painted logs cast from refractory cement, and can warm a room up to 1,300 feet. Gas log sets come in vent-free and vented varieties; this set is a ventless option that does not require a chimney or duct to dispel exhaust. 

This set is available in 18-, 24-, and 30-inch widths, so be sure to pick the set of gas logs that fits your firebox or fireplace. All sizes feature a battery-assisted Piezo ignition with a built-in pilot oxygen depletion sensor (ODS), so it will immediately turn off if it detects carbon monoxide or lack of oxygen.

Final Verdict

The Duluth Forge FDF300R Vent Less Gas Fireplace Insert (view at Amazon) is a practical choice for most homeowners. This ventless model puts out plenty of heat with up to 32,000 BTU and offers dual fuel options. However, if you are looking for a natural-vented option that exhausts through an existing chimney, then consider the Empire Keystone Deluxe B-Vent Fireplace (view at Amazon). This option only outputs up to 21,000 BTU, but natural-vented gas inserts tend to produce more realistic-looking flames.

What to Look for in a Fireplace Insert

Venting Type

One of the most important things to know when buying a gas fireplace insert is what type of vent configuration you need. There are three primary venting types: natural-vented, direct-vented, and ventless. In short, natural-vented gas fireplace inserts require vertical ductwork terminating at the roofline, direct vent models can use vertical ductwork terminating at the roof or horizontal ductwork through an exterior wall, and ventless models require no ductwork for exhaust. 

Fuel Type

Gas fireplace inserts require either a natural gas line or a propane tank for fuel. Natural gas units often produce more heat (measured in BTU per hour), but they need to have a gas line installed. Propane tanks avoid the need for gas line installation, but they require regular replenishment. 

Heating Efficiency

Gas fireplace inserts have varying percentages of heating efficiency, largely dependent on the unit’s venting type. Natural-vented fireplace inserts have the lowest heating efficiency since heat is lost through the open damper or flue. Direct vent fireplace inserts have better heating efficiency because they draw in outside air and use smaller ductwork for exhaust. Ventless gas fireplace inserts have the best heating efficiency since they have no ductwork. Most units operate with 99 percent efficiency and produce a minimal amount of carbon monoxide. However, it is important to monitor oxygen levels in a room with a ventless gas fireplace. In most cases, these types of inserts come equipped with an oxygen depletion sensor.

FAQ
  • Can you install a gas fireplace yourself?

    In most cases, the installation of a gas fireplace is best done by a professional. Some parts of the project, such as the carpentry work to install the firebox and trim might be within DIY capabilities, but other work—like installing exhaust vents, running a gas line, or installing a new electrical circuit—will often require the help of a professional. 

  • How much heat does a gas fireplace provide?

    The amount of heat produced by a gas fireplace insert is measured in BTU, short for British Thermal Units. Heat output varies by model and fuel type, but most gas fireplace inserts produce between 20,000 and 40,000 BTU (some have much higher or lower outputs). 

    Keep in mind that heating efficiency is an important factor to consider since this percentage will determine how much of the heat reaches the room and how much is lost to the venting process.

  • How often should you clean a gas fireplace?

    Generally speaking, you should clean your gas fireplace monthly. While it’s true that gas fireplaces are much less messy than the soot and ashes that come from a wood-burning fireplace, there are still by-products from the combustion process that require cleaning. In addition, cleaning your gas fireplace insert gives you an opportunity to inspect components for any damage that may affect the operability or safety of the unit.

  • How do you remove a gas fireplace insert?

    While actually removing the gas fireplace insert isn’t overly complicated, properly disconnecting and capping the gas line is critical. For this reason, most people hire a professional to handle the work on the gas line or take care of the entire process to remove the gas fireplace insert. 

    However, here is a basic overview of the process to remove a gas fireplace insert: First, shut off the gas supply. Next, remove the trim pieces around the insert. At this point, you can unscrew the gas supply line from the insert. Gently free the insert from the wall or masonry—this step will often require a second set of helping hands. Finally, cap the gas line and test it to ensure there are no leaks.

Why Trust The Spruce?

With more than five years of researching the best products for indoor and outdoor living, Erica Puisis is familiar with the features and benefits that matter the most to homeowners. Her areas of expertise have included home heating and cooling systems and appliances. To find the best options for gas fireplace inserts, she compared the venting type, maximum BTU output, and fuel type of each model considered. All of the options considered provide at least 20,000 BTU of heat, and most are available for natural gas or propane connections.

Article Sources
The Spruce uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. New Safety Standard for Hot-Glass Front Fireplaces. Hearth, Patio & Barbecue Association.

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