Skip to content
Home » Technical blog » Understanding fire safety ratings for high-rise balcony applications

Understanding fire safety ratings for high-rise balcony applications

When it comes to choosing fire safety glass for balustrade applications, there are many different classifications and terms to be aware of. Each of these is important to ensure compliance with the recently amended Building Regulations.

Read on, as Andy Lake, Pyroguard’s Sales Director UK & IRE, aims to shed some light on the ratings to look out for, what they mean and how they’re calculated.

High Rise Balcony Balustrades

What are the current regulations?

First and foremost, it’s vital that you understand the requirements as per the Building Regulations before you start. The latest update to Part B of the Building Regulations states that materials used in the construction of a balcony, on any building that includes a ‘residential’ purpose and stands above 11 metres in height, must be class A2-s1, d0 or better.

But what does this mean? This classification rating can be broken down into three areas: reaction to fire, smoke and droplets…


Reaction to fire

As the name suggests, this is the measurement of how a material or system will react to and potentially contribute to the spread and development of a fire. Here, building products can have a rating from A to F, with an A1 classification the highest that can be achieved. To meet the building regulations for high-rise residential applications, a system need only achieve an A2 rating, this means that the material will contribute very little to the spread of a fire and can even help to act as a barrier for a short period of time. It’s vital to check this rating for any product specified and installed as, in the event of a fire, it’s possible for materials in close proximity to the source to ignite and spread the blaze into other sections of a building.



In the event of a fire, it is vital that a safe escape route is offered to those inside the building, as well as a safe access route to the emergency services. For those who are evacuating, this can be significantly hindered by smoke, which is why the next part of the rating is key.

This is the smoke classification, signified by an alphanumeric combination from s0 to s3, with s0 being the highest. This rating relates to the amount of smoke generated by a burning material, with an s0 rating meaning that there are no smoke emissions, ensuring an easier escape route for those fleeing a burning building.



The final part of the rating covers droplets. This classification is again denoted by an alphanumeric combination, with d0 the highest and d2 the lowest. As well as causing severe injuries, if coming into contact with other combustible materials burning droplets can also contribute to the spread of a fire. In the case of a high-rise residential building, this could mean the difference between a blaze spreading between floors or staying on one floor. A product with a d0 rating means that it doesn’t produce any burning droplets – a key factor when considering building materials for a high-rise balcony application.


How are these ratings tested?

Testing is an integral and extremely important part of producing, supplying and specifying fire safety glass, ensuring the products that we manufacture perform as intended. In the case of the ‘reaction to fire’ rating, as an example, there is one common test: The Single Burning Item (SBI).

This test involves mounting a glass sample within a frame underneath an exhaust system. The glass is then exposed to a fire igniting next to the material. The reaction the specimen has to the burner is measured both instrumentally and visually, including heat and smoke release rates.

This test can give an accurate idea of how a material, like fire safety glass, will react in the event of a fire.


Why is this so important?

It goes without saying that employing an effective passive fire protection strategy is vital in any setting. Following past tragedies there is a clear increased focus on high-rise balcony applications. Forming a focal point of a building’s exterior face, any materials installed here could either contribute to, or help prevent, the spread of a fire. However, by specifying products that adhere to the new classifications, as set by the Building Regulations, glass and glazing systems can ensure the maximum protection for a building’s occupants.

Our Pyroguard Balustrades fire safety glass is the perfect example. With a reaction to fire rating of A2-s1, d0, it meets the required standard to be installed in buildings over 11 metres in height. Not only does this provide architects and specifiers with a safe and compliant external building material, but it also offers a more aesthetic alternative for balcony applications, allowing for quality, contemporary housing to be created.

For further information on Pyroguard Balustrades please contact us.

Further reading

Pyroguard unveils 2024 Technical brochure

Read more

Fire door insight from ‘the door guy’: a Q&A

Read more

Combine performance and aesthetics, with the help of our new Smokeguard brochure

Read more

The latest from our technical team

View all

Pyroguard achieves new success with first 45° Structural Wall System butt-joint

Read more

Largest timber test success with Pyroguard Protect EW60

Read more

NEW timber door solutions for Pyroguard Protect EI30

Read more