Can you boil water in the glass? (1 Thing to be Careful about)

In this brief guide, we will answer the question, can you boil water in the glass? We will discuss the reasons you need to avoid boiling water in ordinary glass and the kinds of glass that can be used for boiling water. We will also discuss the characteristics of pyrex and borosilicate glass.

Can you boil water in the glass?

You cannot boil water in an ordinary glass. However, there are some types of glass that can be used for this purpose. You must avoid subjecting glass to direct flame such as the stovetop. 

You also need to avoid boiling water in glassware or pouring boiling hot water into it. While you can pour hot drinks or beverages in glass, you need to practice caution. The average temperature that ordinary glass is able to hold varies between -5 to 70 celsius. 

Which type of glass should you use to boil water?

Borosilicate and pyrex glass can be used to boil water. Cheap glass does not have such integrity to withstand high temperatures due to impurities at a molecular level. If you boil or even pour hot water into it, it would cause the glass to break and shatter, spilling its content everywhere. 

If you use a pyrex or a good, strong glass to boil water, you need to make sure that it comes down to room temperature before you touch something cold to it. A temperature shock could just as easily make the glass shatter. 

What makes glass shatter and break if you subject it to a high temperature?

Some glass pitchers and flasks are made to withstand high temperatures that do not crack or shatter if you add hot water or drink from them. Hence, it allows you to pour hot water inside. If you are careful, you can boil water into it as well. 

If you use an ordinary glass pitcher to pour hot water inside, it will not be able to withstand the high temperature. 

The inside of the glass which is in contact with hot water would expand while the outside remains the same. A temperature difference between the inside and outside causes the glass to expand more than it would otherwise. 

A difference in the structural integrity of the glass creates stress. As it surpasses the tensile strength, that is the ability of a material to resist force and breakage strength, it shatters. 

Owing to thermal shock, the glass would give in to the pressure and start to crack. 

Tensile strength is force per unit area that measures the maximum load that a material can withstand. Different materials have varying levels of tensile strength. 

When the force applied is less than the tensile strength of the material, then the material bounces back to its original shape, However, if the force exceeds the tensile strength, it breaks and fractures.  

Do all glasses break under stress?

Thermal resistant glasses are made to withstand a high temperature as they have a low thermal expansion coefficient. 

What is Pyrex?

Pyrex is a company that manufactures A-grade utensils that are heat-resistant to such an extent that they can be switched from oven to fridge in no time.  Pyrex uses tempered borosilicate glass which makes it thermal-shock resistant. 

Pyrex guarantees that all of its products make for healthy and safe cooking. They also manufacture metal and ceramic roasters now. 

Borosilicate glass is made with thin or thick surfaces which are both durable. Borosilicate glass allows optical clarity and is safe for microwave and dishwasher use. 

Not only do they make pots and pans for cooking but also laboratory equipment such as beakers and test tubes. Pyrex is not only resistant to heat but to chemicals and electricity as well. 

Pyrex pots and pans are made for baking, cooking. Pyrex has borosilicate that expands only one-third of ordinary glass. 

Pyrex started out in 1915 when a physicist was presented with the problem of cooking utensils being cracked. The physicist then tried to solve the problem with borosilicate glass that was being used for things other than consumer cooking products. 

Borosilicate glass is resistant to thermal shock and has been made to withstand a high-temperature difference. 

Borosilicate glass has a low thermal expansion coefficient which means it has a low tendency to change its structure depending on temperature. A high temperature does not make Borosilicate glass change area, shape, density, or volume significantly. 


In this brief guide, we answered the question, can you boil water in the glass? We discussed the reasons you need to avoid boiling water in ordinary glass and the kinds of glass that can be used for boiling water. We also discussed the characteristics of pyrex and borosilicate glass.


Hi, I am Charlotte, I love cooking and in my previous life, I was a chef. I bring some of my experience to the recipes on this hub and answer your food questions.