You may have heard stories about glass shattering in the oven, or Pyrex being unsafe at higher temperatures. Unfortunately, there are some glass materials that aren’t really suitable for use at higher temperatures.
Since there are different types of glass, we’ll be covering which types are oven-safe, and which are more likely to break or shatter. The last thing you want is to be picking up glass that has exploded in a hot oven.
In this article, we’ll also be going over what causes glass to break in the oven, how to prevent glass from breaking, and how to correctly take care of your glassware and pans!
Can you put Glass in the Oven?
Glass is generally oven-safe if it’s transferred from room temperature into a preheated oven. The two factors that most often lead to shattering are temperature shocks and damaged glass. To prevent shattering, ensure the glassware is marked as oven-safe and inspect it for any scratches or chipped areas.
Untreated glass should never be used in the oven as it has low structural strength that can only handle moderate temperatures. Tempered and borosilicate glass are much stronger than untreated and are more heat resistant and durable.
What Causes Glass to Break in the Oven?
Although glass can safely be used in the oven, there are factors that can lead to shattered glass. We recommend avoiding these risks below in order to prevent your glass cookware from breaking.
1. Extreme Temperature Change
The most common reason that glass breaks in the oven is from temperature shock. Glass is not designed to withstand frequent and quick drops in temperature.
Temperature(thermal) shock occurs when there is a rapid temperature change such as moving from a freezer or fridge to a preheated oven. During this sudden variation of temperature, the glass container will either expand or contract which may lead to breaking.
It is recommended to allow your glass containers to reach room temperature before placing them into the oven to lessen the temperature change. Simply remove your container from the fridge and place it on the counter around 15-20 minutes before you plan to use it in the oven.
There are a few ways that temperature shock can happen so be sure to avoid all different forms of drastic temperature change.
- Going from the fridge to the oven
- Going from the oven to the fridge
- Pouring hot liquid into a cold dish
- Placing a hot dish into cold water
- Placing a hot dish onto a wet countertop
Just remember the conditions above and you won’t find yourself having to clean up pieces of shattered glass!
2. Incorrect Glass Type
There are certain glass products that are useful for many things, but not for the temperatures of an oven. Untreated glass has very low structural strength and can’t support sudden changes in temperature. This glass is the most likely to crack or completely shatter once put high temperatures.
Tempered glass is very strong and heat resistant, and is designed to better hold up against drops or hits on the glass. The higher surface compression of tempered glass makes it around four to five times stronger than untreated glass. Less chance on breaking when dropped sounds great, but it comes with a downside.
If tempered glass does shatter, it will shatter into very tiny pieces that can be a huge pain to clean up. Thankfully, the pieces of glass have less sharp edges compared to other glass types, which can help reduce the chance of being injured by a piece.
The lower resistance to temperature makes the tempered glass more likely to shatter when compared to borosilicate.
Borosilicate glass is the most heat resistant glass that you can get for cookware. This glassware is designed to withstand those more extreme temperatures and changes in temperature.
This cookware type is often thin, durable, and extremely safe for cooking or baking at most temperatures in the oven. There are other key differences besides heat resistance between soda-lime glass and borosilicate glass.
3. Damaged Glass
As long as you have the correct oven-safe glass and a non-damaged container, there should be no issues in the oven. It’s important to inspect your glass cookware often and definitely before you use it at higher temperatures.
Any damaged areas where there are cracks or chips are weak areas in the glass that make it more likely to break on temperature change. To be completely safe, any glass pan should not be used in the oven if there are cracks or chips, no matter the size.
4. High Temperatures in the Oven
Even when the glass is marked as oven-safe, you should consider the temperature the oven will be set at. Some glass may be fine in the oven at certain temperatures, but unsafe once you start reaching those high temps.
Usually, the manufacturer will have a max temperature limit which should never be exceeded for safety reasons. If you’re unsure of the limit and can’t find the information online, it’s best to keep the temperature under 450 F.
How to Prevent Glass From Breaking in the Oven
1. Use the Correct Glass
Only use glass that has been treated and is durable enough to withstand the hot temperatures of an oven. The correct glass types(tempered, borosilicate) will be less likely to experience a thermal break.
2. Check for an Oven Safe Label
Most heat resistant glassware will have a label indicating that it was made for use in the oven. If there is no label and no information can be found, it is not safe to use the glass in the oven.
3. Inspect the Glass for Cracks
Inspect any glass before using it in the oven. Any small chip may be enough damage to ruin the integrity of the glass and cause it to shatter at high temperatures.
How to Know if Glass is Oven Safe
There should be a label on the bottom of your glassware that indicated the glass is safe for use in the oven. A label of “oven-safe” indicates that the pan can be used for baking in the oven, however, that doesn’t mean it can be used for any temperature your oven is capable of. You may also see a symbol with wavy lines and a temperature, which means it can be used in the oven as long as the temperature doesn’t go higher than the number.
Manufacturers will have information on their site about the maximum temperature that the glass can be used in. This would be the next best place to check if there is no label found on the glassware. If no information can be found it may still be safe to use in the oven, but it should be tested at lower temperatures before.
Benefits of Using Glass Containers
As you know there are several options that you can use in the oven, so why choose glass? What benefits do you get from using glass containers that you don’t receive from others?
- Glass Bakeware Absorbs Heat
- Can be Used for Cooking, Serving, and Storing
- Easy to Clean
- Watch Your Food Cook
Looking After Glass Bakeware
We went over how scratches on the pan may lead to a higher chance of breaking, so what’s the best way to prevent that? There are three key steps to follow when cleaning your glass bakeware.
- Combine Baking Soda and Dish Soap
- Soak In Hot Water
- Clean Using A Non-Scratch Pad
These steps provide the best and easiest way to clean your glass pans and Pyrex. You’ll want to use a generous amount of dish soap and mix it with baking soda in the bottom of the glass pan.
Turn on the hot water and let it completely fill up the rest of the space. Before beginning to scrub, let it all sit there for at least 15-20 minutes. This is the most important step as it allows the warm water to remove any tough baked-on food.
Make sure that you only use a non-scratch pad for scrubbing as scratches could eventually lead to cracked glass. After your pan has soaked for 15 minutes, scrub thoroughly with a non-scratch pad, in order to keep the glass smooth and scratch-free.
Can You Put Pyrex Glass In The Oven?
Pyrex is one of the most popular glassware on the market, so you might be wondering what type of glass it’s made of. Their products used to be made from borosilicate glass but are now made from soda-lime(or tempered) glass.
According to Consumer Reports, in 1998 Pyrex made the switch to soda-lime glass, most likely because it’s a cheaper material. Some people may actually still have the original glass from before 1998!
Now that we now what Pyrex is made from, let’s find out if it’s safe for oven use.
As long as you follow proper procedures and limit the amount of temperate change on the material, you most definitely can put Pyrex glass in the oven.
If you want to know more about Pyrex, the FAQ section on their site is a great resource.
Can you put glass in the oven? There are a few factors that can make using glass in the oven unsafe, but for the most part, you can safely use glass in the oven. Untreated glass should never be used in the oven, while tempered and borosilicate glass are fine at lower temperatures.
It’s important to always check for an oven-safe label on the glassware before placing it in a heated oven. As long as the glassware is made of oven-safe glass, isn’t cracked or chipped, then it should be completely safe for use in an oven.