Understanding security doors: What is a metal gauge?

When you're considering which metal product to purchase, you may see terms such as gauge thrown around, but what does that actually mean? Once you understand gauge it is far easier to make informed decisions on which products are going to work best for you.

The gauge system started out in the 19th century when it was used mostly for wire production. Since then, the gauge system has been used across a wide variety of metal products. Initially, the gauge system was based on how many turns through a wire rolling mill the wire needed to go through to reach the desired thickness.

Now a gauge can be used for almost any metal sheet. For example, if you were buying steel security doors or fire exit doors, these would come with a gauge that would let you know how thick the metal sheets were that are used to construct the doors. Similarly, if you were buying thin metal for making a car, you would also have a gauge to help determine how thick the metal is.

If you're looking in terms of heavy duty steel security doors, you'll obviously want a thicker metal that contributes to the security features of your door.

The gauge system goes from low to high - this means that thicker metal is assigned a lower gauge, and thin metal is given a higher gauge number. The inverse measurement system provides a standardised measurement system that ensures consistency in metal products.

Understanding gauge gets more complex when considering the measurement itself - because it isn't technically a measurement. Gauge will differ between materials and measurement and is not absolute. For example, the metal used in a steel security door might be a different gauge to a aluminium door, even if the steel sheet measures to be the same width.

For this reason, a gauge chart is often needed. To put an example into practice a 10 gauge can look like this:

• Steel - around 3.42mm
• Aluminium - around 2.59mm
• Galvanised steel - around 3.51mm

Often, steel doors are selected for their additional security benefits, to be used as a fire rated fire exit door or simply for a durable door solution. Therefore, you'll want to make sure that when you're selecting your steel doors, you're choosing one that is made from steel that is the right gauge for you.

As mentioned above, the lower the gauge, the thicker the metal. If you're after a secure door solution then it may be beneficial to seek out those made with lower gauge steel. However, you should bear in mind that often doors are made up of more than one sheet of steel, so a gauge is not necessarily entirely reflective of the thickness of your door.

Another thing to consider if that the thicker steel, the heavier a door can become. This might mean that door closers are needed if they are being used as personnel doors or entrances to prevent heavy doors from slamming or causing injury.

If you want to find out more about the steel gauge that our steel security doors offer, our team are passionate about providing the best service and are happy to help provide you with additional information.