Best Fireplace Insert for a Zero Clearance Fireplace (2026): 5 Compared
Five inserts for a zero clearance fireplace compared on heat and fit: a 32,000 BTU ventless gas insert, a zero clearance firebox and three electric inserts.

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Top picks at a glance
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- 1
Best real heatDuluth Forge Dual Fuel Insert9.6/10View on Amazon - 2
Best for buildersProCom Ventless Firebox9.5/10View on Amazon - 3
Best small electricInnoflame Electric Insert 23in9.4/10View on Amazon - 4
Best wide electricTangkula Electric Insert 36in9.4/10View on Amazon - 5
Best widest viewXbeauty Electric Insert 37in9.4/10View on Amazon - 6
Duluth Forge Dual Fuel Ventless Gas Fireplace InsertView on Amazon - 7
ORALNER 23” Electric Fireplace InsertsView on Amazon - 8
PuraFlame Western Electric Fireplace Insert with FireView on Amazon - 9
Electactic 60 Inch Electric Fireplace Insert Ultra-ThinView on Amazon - 10
PuraFlame Klaus 33" Electric Fireplace Insert 750/1500W heaterView on Amazon
The best fireplace insert for a zero clearance fireplace depends on which kind of insert you mean, and this list holds all three: a complete ventless gas insert with its own burner, a zero clearance firebox that waits for a log set, and three electric inserts that slide into the opening. We compared five on stated heat output, coverage, fit and safety features, using only what each listing publishes. Only two of the five are zero clearance products in the strict sense, and the scores say so.
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Quick picks
- Best real heat Duluth Forge Dual Fuel Insert: 32,000 BTU of ventless gas in a zero-clearance box. Check price on Amazon
- Best for builders ProCom Ventless Firebox: A zero clearance firebox that takes any log set. Check price on Amazon
- Best small electric Innoflame Electric Insert 23in: 23 inches, CSA/UL listed, with a stated warranty. Check price on Amazon
- Best wide electric Tangkula Electric Insert 36in: 36 inches of ETL certified flame and heat. Check price on Amazon
- Best widest view Xbeauty Electric Insert 37in: 37 inches, with a touch screen and remote. Check price on Amazon
The picks

Duluth Forge Dual Fuel Ventless Gas Fireplace
For real heat in a zero clearance box: a ventless dual fuel gas insert at 32,000 BTU, heating up to 1500 sq. ft, with a remote.
Pros
- 32,000 BTU, the only whole-room heat here
- Runs on natural gas or liquid propane
- Zero-Clearance Firebox, named for this keyword
- Oxygen Depletion Sensor and automatic shut off stated
Cons
- Needs a gas line to the firebox
- 69.5 lbs and a 42 inch ceiling clearance rule
- Warranty is Limited with no term stated
- Ventless gas is not legal everywhere; check local code

ProCom 32in. Universal Ventless Firebox Insert
For building your own unit: a zero clearance ventless firebox, 35 inches wide, that takes any ventless gas log set of 18 or 24 inches.
Pros
- Approved for zero clearance installation, stated
- Takes any ventless gas log set, 18 or 24 inch
- Slim profile for tight spaces
- Draw screen, hood and brick liner included
Cons
- A firebox only: the log set is a separate purchase
- Heat output depends on the log set you add
- 64 lbs to recess into a wall
- Warranty is Limited with no term stated

23" Electric Fireplace Insert
For a small opening and simple heat: a 23 inch electric insert at 5000 BTU for rooms up to 400 sq ft, with a thermostat and remote.
Pros
- CSA/UL listed, with overheat protection
- Thermostat range of 64F-82F stated
- 1 year manufacturer warranty, the only stated term
- Mounts from the rear for a flush built-in look
Cons
- 23 inches is the smallest front here
- 5000 BTU is one room's warmth, not a house's
- Rear mounting needs access behind the furniture
- Flame has 4 brightness levels, fewer than rivals

Tangkula 36 Inches Electric Fireplace Insert
For a wide electric view: a 36 inch recessed insert at 5000 BTU, with 3 flame colours, 5 brightness levels and an 8H timer.
Pros
- 36 inches wide, a full fireplace view
- ETL certification stated, with overheat protection
- 3 flame colours and 5 brightness levels
- Dual heat settings, 750W and 1500W
Cons
- 5000 BTU covers up to 400 sq ft, as stated
- Needs 12 inch clearance from a TV above, per the listing
- Warranty is Limited with no term stated
- Flame and heat share one 1500W ceiling

Xbeauty 37" Built-in Electric Fireplace Insert
For the widest electric: a 37 inch built-in insert with 3 flame colours, a touch screen and separate flame and heat controls.
Pros
- 37 inches, the widest front here
- Touch screen plus an 8m remote
- Flame and heat controlled separately
- 5100 BTU stated heat output
Cons
- Coverage conflicts: the table says 120 square feet
- 60 pounds, the heaviest electric here
- Insert opening tolerances are tight, 36-36.6 inches wide
- No warranty statement in the data here
More options to compare
Duluth Forge Dual Fuel Ventless Gas Fireplace InsertCheck price on Amazon
ORALNER 23” Electric Fireplace InsertsCheck price on Amazon
PuraFlame Western Electric Fireplace Insert with FireCheck price on Amazon
Electactic 60 Inch Electric Fireplace Insert Ultra-ThinCheck price on Amazon
PuraFlame Klaus 33" Electric Fireplace Insert 750/1500W heaterCheck price on Amazon
Compare the picks
| Insert | Type | Heat output | Coverage | Fit | Warranty |
|---|---|---|---|---|---|
| Duluth Forge Dual Fuel Insert | Ventless gas insert | 32,000 BTU | 1500 sq ft | Zero-clearance firebox | Limited |
| ProCom Ventless Firebox | Ventless firebox | 26,000 BTU stated | Not stated | 35″ W x 19″ D | Limited |
| Innoflame Electric Insert 23in | Electric insert | 5000 BTU | 400 sq ft | 23″ front opening | 1 year |
| Tangkula Electric Insert 36in | Electric insert | 5000 BTU | 400 sq ft | 36 inches | Limited |
| Xbeauty Electric Insert 37in | Electric insert | 5100 BTU | 120 sq ft per table | 37 inches | Not stated |
21 October 2026
How we scored them
The Woodlot Score weighs performance, build, value, safety and warranty. Performance is heat delivered into the room: 32,000 BTU of gas against 5000 BTU-class electrics is not a close contest. Safety credits the stated sets: the gas insert’s Oxygen Depletion Sensor and shut off, the firebox’s zero clearance approval, and the electrics’ ETL or CSA/UL listings with overheat protection. Only the Innoflame states a warranty term. How we pick explains the weights.
| Product | Woodlot Score | Perf. /35 | Build /25 | Value /25 | Safety /10 | Warranty /5 |
|---|---|---|---|---|---|---|
| Duluth Forge Dual Fuel Insert | 9.6 | 33 | 21 | 18 | 9 | 0 |
| ProCom Ventless Firebox | 9.5 | 28 | 20 | 16 | 8 | 0 |
| Innoflame Electric Insert 23in | 9.4 | 24 | 16 | 15 | 7 | 3 |
| Tangkula Electric Insert 36in | 9.4 | 27 | 18 | 18 | 7 | 0 |
| Xbeauty Electric Insert 37in | 9.4 | 26 | 16 | 16 | 7 | 0 |
Scores run from 9.2 to 9.8: each product’s point total is placed on that range, so more points always means a higher score.
Buying guide: choosing the best fireplace insert for a zero clearance fireplace
Zero clearance is a rating, not a shape
A zero clearance fireplace is a factory-built firebox that can sit against combustible framing because its own insulation keeps the outside cool. An insert for it must carry its own approval for that use: the Duluth Forge names a Zero-Clearance Firebox, and the ProCom states approval for zero clearance installation. The electrics make no such claim and need none, since they produce no combustion; they still must fit the opening the maker states. For the wood-burning side of the room, our best fireplace screen for a prefab fireplace covers the front.
Gas heat and electric heat are different purchases
The gas insert heats a stated 1500 sq. ft; the electrics heat 400 sq ft or, on the Xbeauty’s own table, 120. If the insert is your heat, the gas unit is the only candidate here. If it is evening flame with a little warmth, the electrics are simpler, need no gas line, and run flame without heat all summer.
Measure the opening, then read the fit twice
Every listing here gives a fit figure, and they are all different in kind: a front opening of 23 inches on the Innoflame, an insert opening of 36 to 36.6 inches on the Xbeauty, a 42 inch ceiling clearance on the Duluth Forge. Measure your firebox and your mantel clearances before falling for a width, because an insert that almost fits fits nothing.
Match the heat figure to the room
Heat output decides which insert is a heater and which is a view of fire. The Duluth Forge states 32,000 BTU from its ventless dual fuel burner, heating up to 1500 sq. ft, and calls the burner 99.9% efficient in the bullets. It runs on natural gas or liquid propane, with a standing pilot so the remote can turn the flame on and off, manual flame adjustment and push button Piezo ignition. If the insert is the room’s heat source, this is the only one of the five built for that job.
The ProCom firebox sits in the middle: its spec table states a 26,000 BTU heat output and 1800 square feet of heating coverage, but the heat comes from the ventless gas log set you fit into it, 18 or 24 inches, bought separately. Its unique airflow system is claimed to move more heat into the room across an extra-large viewing area, and it is approved for zero clearance installation against or recessed into a wall accessible to a gas line.
The three electrics are single-room warmth. The Innoflame states 5000 BTU for rooms up to 400 sq ft on 1400W, with a thermostat adjustable from 64F to 82F. The Tangkula states 5000 BTU over up to 400 sq ft with dual 750W and 1500W settings and a temperature hold between 62F and 82F. The Xbeauty states 5100 BTU, with dual 750 and 1500W heating and a 1 to 8H timer; treat the coverage figure with care, since the bullets say up to 400 sq ft while the spec table says 120 square feet. All three are vent free, so no chimney or duct is needed.
Weight, depth and clearances before you lift
The gas units are the heavy ones. The Duluth Forge lists 69.5 lbs in the bullets and 70 pounds in the spec table, at 29.1 in W by 15.6 in D with 42 inches of clearance required from the top of the fireplace to the ceiling. The ProCom lists 64 lbs in the bullets and 69.1 pounds in the spec table, at 32.5 in H by 35 in W by 19 in D. Plan the carry path and the helpers before the box arrives.
The electrics are lighter but fussier about depth. The Innoflame is 19 pounds with a 5 in chamber depth, a furniture front opening of 23 in W by 19 3/4 in H, and a stated install: slide the unit forward from behind the furniture until it sits flush, then tighten the screws. The Tangkula is 30.5 pounds at 5.7 in D by 36 in W by 21.5 in H, fitting openings of 29.1 or 32.1 in W by 5.9 in D by 19.7 in H, and asks for 12 inches of clearance from a TV above. The Xbeauty is 60 pounds at 37 in W by 6.5 in D by 26.02 in H, with an insert opening of 36 to 36.6 in W by 6.9 to 7.9 in D by 25.43 to 25.74 in H, and includes a side handle for setup.
Fuel, power and controls
Gas inserts need a gas line; electrics need an outlet. The Duluth Forge is dual fuel, natural gas or liquid propane, with a remote with an LCD screen, a standing pilot, manual flame adjustment and push button Piezo ignition, and takes 3 AAA batteries per the spec table. The ProCom is gas powered and installs against or recessed into any wall accessible to a gas line, then takes any ventless gas log set of 18 or 24 inches. Both are vent free, so neither needs an outside duct or chimney.
The electrics trade the gas line for a plug and simpler controls. The Innoflame runs 1400W with a remote and a control panel, 2 AAA batteries, adjustable 4 flame brightness, a thermostat from 64F to 82F and 1 to 8H timers for overnight use. The Tangkula’s hand remote works from a 20 ft range with flame settings, heating levels, temperature and an 8-hour timer, on dual 750W and 1500W heat. The Xbeauty uses a touch screen plus an 8m remote, 3 flame colours at 5 brightness levels, flame speed and dimmer control, a 1 to 8H timer, and a flame-only mode that runs the look of fire without heat.
Install stoves and inserts to the manufacturer's instructions and your local code, usually by a certified installer with a permit and inspection. Keep the listed clearances to combustibles, run working smoke and carbon monoxide detectors, have the chimney inspected and cleaned every year to prevent creosote fires, burn only seasoned wood, and check local burn rules. See EPA Burn Wise, NFPA heating safety, CPSC carbon monoxide guidance and the Chimney Safety Institute of America (CSIA). Read our Safety Disclaimer.
Frequently Asked Questions
What is a zero clearance fireplace?
A factory-built firebox designed to be installed against combustible materials, with its own insulation. Inserts for it should state zero clearance approval or, for electrics, simply fit its opening.
Which insert heats the most?
The Duluth Forge, at a stated 32,000 BTU and up to 1500 sq. ft. The electrics state 5000 to 5100 BTU for single rooms.
Can I put an electric insert in a prefab fireplace?
Yes, where it fits the stated opening. The three electrics here are vent free and need no chimney; check the maker’s opening figures and clearances.
Does the ProCom firebox include the logs?
No. It includes a draw screen and hood, and takes a ventless gas log set of 18 or 24 inches, bought separately.
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