Best Fireplace Draft Stopper (2026): 5 Hearth Covers and Plugs Compared
Five fireplace draft stoppers compared by cover or plug design, dimensions, materials, magnet strength and how each seals against chimney airflow.
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Top picks at a glance
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- 1
Best OverallFlueblocker Round Plug9.7/10View on Amazon - 2
Best Full-Face Coverwhumsdog 39×32 Cover9.6/10View on Amazon - 3
Best for Mid-Size Hearthswhumsdog 36×32 Cover9.6/10View on Amazon - 4
Best Inflatable PlugBattic Door LGDS Plug9.4/10View on Amazon - 5
Best for Fireplace VentsBeeplove 36×6 Strips9.4/10View on Amazon
When winter burning season winds down or the hearth sits cold between evening fires, an open chimney acts like an open window, pulling warmed room air up the flue and dumping chilly drafts into living spaces. Finding the best fireplace draft stopper is the simplest way to seal that opening without permanently altering your hearth. A proper draft stopper closes off air leaks, stops downdrafts and keeps conditioned air inside the room whether you have an open masonry hearth, a zero-clearance insert or decorative fireplace vents. This guide compares five draft stoppers across magnetic face blankets, inflatable damper pillows and dense wool flue plugs.
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Quick picks
- Best Overall Flueblocker Round Plug: Dense Herdwick wool compression plug that blocks drafts in 8 to 9 inch round flues without needing a working damper. Check price on Amazon
- Best Full-Face Cover whumsdog 39×32 Cover: Twelve built-in magnets with 1.2 T suction force seal a 39 by 32 inch flame retardant blanket across an iron fireplace frame. Check price on Amazon
- Best for Mid-Size Hearths whumsdog 36×32 Cover: A 36 by 32 inch quilted oxford cloth blanket with 12 magnets designed to cover iron frames and stop chimney airflow. Check price on Amazon
- Best Inflatable Plug Battic Door LGDS Plug: Inflatable polyurethane pillow with a telescoping pole that seals rectangular dampers up to 38 by 16 inches. Check price on Amazon
- Best for Fireplace Vents Beeplove 36×6 Strips: Two flexible rubber magnetic strips measuring 36 by 6 inches that trim to fit metal fireplace intake and exhaust louvers. Check price on Amazon
Flueblocker Plug for 8-9 Inch Round Chimney Flue
A 100% Herdwick wool round flue plug made in England that pressure-fits into 8 to 9 inch round flues to seal drafts without needing a working damper.
Pros
- 100% Herdwick wool from the English Lake District compresses to seal 8 to 9 inch round flues
- Pressure fit works with a functional, broken, stuck or missing damper
- Can be trimmed with scissors for a custom fit
- Certified under the BBA Agrement Certificate for material performance
Cons
- No warranty term is stated
- Cannot be used with active vented gas log sets without shutting off gas
- Must be removed before lighting any wood fire
- Limited to 8 to 9 inch round flues unless trimmed or sized up
Magnetic Fireplace Cover 39"x32" Fireplace Draft
A 39 by 32 inch magnetic fireplace blanket made from flame retardant oxford cloth with 12 built-in magnets for iron fireplace frames.
Pros
- 12 built-in magnets with 1.2 T stated suction force per magnet
- Thickened flame retardant oxford cloth with insulating sponge filling
- Listing specifies sizing for fireplace openings with 37 by 30 inch inner dimensions
- Folds flat for compact seasonal storage
Cons
- No warranty term is stated
- Magnets attach only to frames containing iron, cobalt or nickel
- Spec table incorrectly lists finish as powder coated for a cloth blanket
- Listing warns magnets lose magnetic performance if exposed to high heat
Magnetic Fireplace Cover 36"x32" Fireplace Draft
A 36 by 32 inch flame retardant oxford cloth fireplace blanket with 12 built-in magnets that seals against iron fireplace frames.
Pros
- 12 built-in magnets provide 1.2 T magnetic suction force per magnet
- Flame retardant oxford cloth exterior with split-line quilted sponge interior
- Blocks drafts across a 36 by 32 inch iron fireplace frame
- Folds easily when removed during active burning
Cons
- No warranty term is stated
- Listing omits specific inner frame opening guidance given on other sizes
- Spec table contradicts bullets by listing finish as powder coated
- Magnets will not adhere to non-ferrous trim like aluminum, brass or masonry
Fireplace draft stopper
An inflatable polyurethane draft stopper pillow with an included telescoping support pole for masonry fireplaces with dampers up to 38 by 16 inches.
Pros
- Seals rectangular dampers measuring up to 38 by 16 inches
- Includes a telescoping pole to prop and position the pillow below the damper
- Polyurethane pillow sits inside the firebox out of room view
- Single unit fits most masonry brick fireplaces
Cons
- No warranty term is stated
- Listing does not state product weight or polyurethane material thickness
- Inflatable design can puncture on sharp damper edges or mortar
- Requires manual inflation and periodic pressure checks
Magnetic Fireplace Draft Stopper
A two-pack of 36 by 6 inch flexible magnetic rubber vent covers designed to seal fireplace air circulation louvers and grates.
Pros
- Includes two 36 by 6 inch magnetic rubber vent strips
- Material cuts easily with scissors to fit custom louver openings
- Smooth magnetic side adheres directly to iron, nickel or cobalt vent grates
- Wipes clean with a damp towel and stores flat on a refrigerator
Cons
- No warranty term is stated
- Maker warns product will melt if applied to a hot or warm fireplace
- Contradiction between 36 by 6 inch listing title and 15.5 by 95 cm part number
- Only seals narrow 6-inch vents rather than a full firebox opening
Compare the picks
| Model | Woodlot Score | Design | Coverage or fit | Material | Attachment | Weight |
|---|---|---|---|---|---|---|
| Flueblocker Round Plug | 9.7/10 | Round flue plug | 8-9 in round flue (10 in diam.) | Herdwick wool | Pressure fit | 8 ounces |
| whumsdog 39×32 Cover | 9.6/10 | Full face blanket | 39 x 32 in (inner frame 37 x 30 in) | Oxford cloth, sponge | 12 built-in magnets | 16 ounces |
| whumsdog 36×32 Cover | 9.6/10 | Full face blanket | 36 x 32 in | Oxford cloth, sponge | 12 built-in magnets | 0.52 kg |
| Battic Door LGDS Plug | 9.4/10 | Inflatable damper plug | Dampers up to 38 x 16 in | Polyurethane | Telescoping pole | Not stated |
| Beeplove 36×6 Strips | 9.4/10 | Louver vent strip | 36 x 6 in (2 pcs) | Rubber | Magnetic face | Not stated |
Specifications are manufacturer rated, collected 13 October 2026. None of these listings states a warranty term with a concrete duration, and none names an official hearth safety standard, so all five score zero for safety and zero for warranty.
The picks: best fireplace draft stopper
How we scored them
Each draft stopper is scored out of 10 on performance, build, value, safety and warranty, using only what the listing publishes. The weights follow our standard Woodlot Score criteria.
| Product | Woodlot Score | Perf. /35 | Build /25 | Value /25 | Safety /10 | Warranty /5 |
|---|---|---|---|---|---|---|
| Flueblocker Round Plug | 9.7 | 30 | 22 | 21 | n/a | 0 |
| whumsdog 39×32 Cover | 9.6 | 28 | 20 | 21 | n/a | 0 |
| whumsdog 36×32 Cover | 9.6 | 27 | 20 | 21 | n/a | 0 |
| Battic Door LGDS Plug | 9.4 | 26 | 18 | 19 | n/a | 0 |
| Beeplove 36×6 Strips | 9.4 | 22 | 18 | 19 | n/a | 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. Safety counts only for powered gear or where the listing states safety features; where it does not apply, the score is taken over the remaining 90 points.
Buying guide: choosing the best fireplace draft stopper
Face blankets vs flue plugs
Draft stoppers fall into two primary designs: exterior face covers and internal flue plugs. Magnetic covers hang on the outside of an iron or steel fireplace frame, creating a thermal barrier right across the opening. They are simple to put up and remove between fires. Flue plugs fit inside the chimney throat or round flue pipe above the firebox, sealing the draft path out of sight. A throat plug stops cold air before it enters the firebox, while a face blanket stops drafts from spreading into the living room even if your firebox has minor mortar gaps.
Measuring your fireplace opening or flue
Fit is critical for draft prevention. For magnetic covers, measure the outer dimensions of your ferrous metal frame to confirm the blanket will overlap the opening. The maker of our top-rated magnetic blanket recommends measuring the inner opening diameter and selecting a blanket that extends beyond it by at least one to two inches. For internal plugs, measure the damper opening or round flue diameter. A compression wool plug should have a slightly larger stated diameter than the flue pipe so it forms a tight pressure seal without falling.
Materials and heat precautions
Fireplace draft stoppers are designed exclusively for inactive, cooled hearths. Oxford cloth blankets with sponge filling and flexible rubber strips can melt or scorch if installed near hot embers or warm metal. Neodymium magnets also lose magnetic strength when subjected to sustained elevated temperatures. Always wait until the fireplace is completely cold to the touch before mounting any draft cover. Natural wool plugs offer dense fiber construction that resists packing down over seasons of use.
Draft control on vented gas logs
Gas fireplaces present specific draft considerations. Building codes typically require dampers on vented gas log sets to be permanently clamped open to prevent carbon monoxide buildup. You must never insert a flue plug or block airflow while gas logs are connected and capable of firing. Any gas supply must be shut off and properly disabled before placing a seasonal plug in the flue, and the plug must be taken out before relighting.
Sealing zero-clearance fireplace louvers
Prefabricated metal fireplaces often draw cold air through upper and lower circulation louvers rather than the main firebox opening. Magnetic vent strips provide a narrow solution tailored to these slots. Flexible magnetic rubber rolls can be trimmed with ordinary utility shears to match the exact length and width of your louver grates, keeping drafts from bypassing closed fireplace doors.
Wear eye protection and gloves for cutting, splitting and handling, follow every tool's manual, install stoves to code, and have the chimney inspected and cleaned every year. See EPA Burn Wise and NFPA heating safety. Read our Safety Disclaimer.
Around the Woodpile
- Never install a draft stopper while a fire burns: always wait until the open fire is completely extinguished and the firebox cools to room temperature before mounting magnetic covers or plugs.
- If using a chimney flue plug with a gas fireplace, ensure any active gas log source is turned off or disabled before installation, and remove the plug before lighting any fire.
- Straighten curled magnetic vent strips or vacuum-packed covers before mounting: vent strips can be smoothed on a refrigerator, while folded fabric covers should hang in a ventilated area for 24 hours to regain full thickness.
- Protect magnetic covers from excessive heat to avoid weakening magnetic strength, and store flexible blankets folded flat when burning wood.
Frequently Asked Questions
Do fireplace draft stoppers work?
Yes. A snug draft stopper blocks the convective flow of air through an idle chimney, keeping warm indoor air from escaping up the flue and preventing downdrafts from entering the home.
How do you stop drafts from an open fireplace?
You can stop drafts by installing a magnetic cover over the metal frame opening, inserting a dense wool plug into the round flue, or placing an inflatable pillow below the rectangular damper.
How do you stop drafts from a gas fireplace?
For gas fireplaces with circulation vents, magnetic rubber strips seal metal louvers. If installing an internal flue plug, you must completely disable or turn off the gas supply first.
Can you use a fireplace draft stopper while a fire is burning?
No. Draft stoppers must only be used on completely cold, inactive fireplaces. They must be removed before lighting wood or gas fires to allow smoke and exhaust gases to exit safely.
Where does a fireplace draft stopper install?
Magnetic blankets mount directly to the exterior iron frame of the fireplace. Inflatable plugs sit directly below rectangular dampers, and compression wool plugs press into the round flue opening above the firebox.
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