How To Repair Broken Fireplace Glass

How To Repair Broken Fireplace Glass
  • Author: Amanda Arnold
  • Posted On: April 12, 2022
  • Updated On: August 21, 2023

Has your fireplace’s glass cracked or been shattered due to a knock from your fire logs? The two most typical causes of cracking are impact and use. Toughened glass can abruptly break for no apparent reason, leading to exploding glass.

The most typical causes are glass binding in the frame, which generates tensions as the glass expands and contracts to owe to thermal changes or deflect due to wind.

What Are The Main Reasons For Broken Fireplace Glass?

Reasons For Broken Fireplace Glass

Vulnerabilities to Heat Tempered glass is used for most fireplace glass doors. On the other hand, higher temperatures age the glass, which means it will eventually fail and shatter. Then there’s thermal expansion and contraction; if the glass expands too much, it rubs against the metal frame, producing the same effect.

If the glass grows too much, it will break into small fragments. To avoid glass shattering, keep the doors open while there’s a roaring fire and keep an eye on the temperature of your fire. Your fireplace glass door may break if the glass is not correctly tempered.

Therefore, ceramic glass is better adapted to extreme high-heat circumstances than tempered glass. However, tempered glass is more cost-effective and yet extremely durable. Tempered glass is commonly utilized when the glass may need to be replaced.

Life Span Of Fireplace Glass

Life Span Of Fireplace Glass

Doors for fireplaces with glass generally last for a decade or more. However, the doors’ longevity will gradually decrease each time a fire is lit. This is so that the glass door’s strength isn’t reduced and diminished every time it is subjected to intense heat.

Glass is more susceptible to the contraction and expansion caused by heating and cooling when it is weaker.  It is safe to presume that replacing the glass doors with material that has not been exposed to fire for a long time is okay if they look like they were built decades ago.

Sudden Thermal Changes

Sudden Thermal Changes

A metal frame encircling the firebox’s entry keeps most of the glass doors, if not all, enclosed. Glass expands as it warms. On the other hand, it shrinks as it cools. The glass will expand if a fire becomes too hot or heats up too quickly, which cannot be stopped by the window’s metal frame. The glass may shatter or split if that occurs.

Replace it with a metal mesh screen if you’re still concerned about sparks or hot surfaces.

Wrong Fireplace Glass Door

 Wrong Fireplace Glass Door

Tempered glass is required for prefabricated fireplaces, whereas ceramic glass is needed for brick fireplaces. Tempered glass doors shouldn’t be closed while a fire is burning. However, ceramic glass doors can if necessary. A fireplace’s glass doors’ durability is greatly influenced by its type and quality.

The glass’s inner surfaces become stiff, and its outer surfaces compress during the tempering process. This glass will shatter into smaller fragments that stay together in addition to rising in temperature and breaking resistance.

Steps To Repair A Broken Fireplace Glass

Having a crack in your glass fireplace cover can be aggravating and unattractive. Though glass fireplace covers are meant to endure considerable abuse, even dogs can produce minor cracks or chips in the glass.

If you want to fix anything, hire an expert or attempt it yourself. You’ll need a glass sander, a screwdriver, and patience if you choose the latter option.

Use A Screwdriver To Remove the Fireplace Cover

Use A Screwdriver To Remove the Fireplace Cover

Remove the fireplace cover first. An ordinary screwdriver will suffice for this. Remove the cover, then the panel with the crack. This should be placed on a hard, flat surface.

Use Sander To Seal Cracks

Apply a gentle sanding motion to the crack with your glass sander. Up and down the crack, move the sander. The glass should be smoothed out as a result of this.

Use Sander To Seal Cracks

If your glass is too badly broken to respond to the sander, you must remove and replace it with another. Get a piece of safety glass made by a local glassmaker and install it in the fractured glass.

Frequently Asked Questions

Is it good to close the fireplace glass door?

While a fire is burning, it’s advised never to close tempered glass doors; nevertheless, ceramic glass doors can be closed. Doing this lets, you keep the fire from losing heat and keep the house free of smoke and embers.

Can you fix the fireplace glass door cracks?

Yes, you can! By loosening the nuts or bolts, the broken glass can be released. Reinstall the glass panel and reseal it.

Can you fix fireplace glass cracks with glue?

You can use Loctite’s super glue glass when making minor repairs to shattered glass. With its ability to connect glass to metal and glass to glass, this high-strength superglue is ideal for last-minute repairs. It also makes immediate, crystal-clear bonds.


Suppose you don’t repair your fireplace’s glass. In that case, you risk it shattering the next time you use it because higher temperatures often nearly exacerbate a crack in the glass. Alternatively, you might have a familiar glass business cut a replacement glass window for your fireplace to your specifications.

Avatar photo
Author: Amanda Arnold

Amanda has been working with ConstructionHow since 2021. Her experience spans over 5 years in the creative niche such as home decor and trends, landscaping, renovations, and custom architectural values. As a home designer expert, she has a keen eye for the latest home improvement trends with accurate facts that readers find impossible to ignore. Being invested in home-building trends is how she has gained her lucrative expertise exploring more to bring a positive ambiance for all homeowners (and even tenants!). Currently, she lives in a beautiful beach home, a source of fascination for her.