Asbestos Flue Pipes - Everything You need to Know

Written by Tom Yates . Edited

Fact Checked by William Wright, NEBOSH

Asbestos flue pipes were especially common before the 1990s and they provided an effective exhaust system for boilers. Although rare today, there is still a possibility that your property could contain one so the below provides a comprehensive guide including how to identify them, and the potential risk factors.

Understanding Asbestos Flue Pipes

Today, flue pipes are usually created using metals like stainless steel or aluminium but before the 1990s a common product was the asbestos flue pipe. This was typically a combination of asbestos and either cement or asbestos paper and moulded into pipes. A flue pipe is essentially a sealed passage through which exhaust gases and heat can be vented without posing a fire hazard. 

In older properties, although the original boiler has probably long since been replaced, the original asbestos flue pipe could still remain and pose a potential health hazard.

Why Was Asbestos Used to Create Flue Pipes?

Asbestos flue pipes were commonly used because of their durability and fire resistant properties. Gases and excess heat or steam from your heating system could safely be ejected via the flue without causing any damage.

What Do Asbestos Flue Pipes Look Like?

Asbestos flue pipes were characterised by their chalky white/grey appearance and rough fibrous texture on the flue opening. However, sometimes the flue pipe would be painted over in different coloured materials like black bitumen which can make identification harder. 

If you suspect your boiler flue pipe contains asbestos, the safest thing to do is to take a sample and have it tested or get an asbestos surveyor out to take a look. You can then send the sample off to the lab for analysis to determine if it contains asbestos or not. 

Are Asbestos Boiler Flue Pipes Still Common in the UK?

Considering the average boiler life in the UK is between 10-15 years[1], the likelihood of you having asbestos flue pipes in your heating system is minimal. 

For example, even if your boiler was 20 years old in 2023, that means it was manufactured and installed in 2003 and asbestos flue pipes should have long-since stopped being used since 1999. Therefore, unless your boiler or heating system is ancient and touching 25+ years old, there really shouldn’t be any asbestos.

This is generally the only place flue pipes were used in the UK so other than your heating system or venting system, there shouldn’t be the possibility for asbestos flue pipes anywhere else.

Bear in mind though that you could have had a replacement boiler, but never changed the original flue pipe so we can’t categorically say that no UK households should contain asbestos flue pipes. You really need to know when your boiler flue pipe was last changed and this should give a clear indication of the possibility of asbestos.

How Dangerous Are Asbestos Flue Pipes? 

Asbestos flue pipes are usually associated with boilers and are thus not subject to wear and tear from external conditions. Additionally, the pipes are considered non-friable which means you can’t crumble the material by hand. Both of these factors means asbestos flue pipes are less dangerous than something like asbestos insulation. 

Regardless, there is still a health risk, especially if the flue has visible damage. Damaged asbestos products have a greater chance to release airborne fibres which can then be inhaled and cause serious health issues like asbestosis and mesothelioma.

If you verify that your boiler flue pipe contains asbestos and it is damaged, we advise seeking the services of a professional asbestos removal service. If the flue contains asbestos, there is also a high possibility that other components of the boiler contain asbestos too such as the gaskets and rope.

 References

[1] – Heatable.co.uk – Lifespan of Domestic Boilers in the UK