14th Feb 2022

Fireproof Insulation And Other Fire-Resistant Building Materials

When you’re embarking on a self-build project, it’s important to think not just about the energy efficiency of the building materials you’re using, but also how fireproof they are.

Statistics from Ireland’s Department of Environment, Housing and Local Government, which have been analysed by the Irish Times, show that 277 people died in 249 fatal house fires between 2010 and 2019, highlighting the importance of making your home as fireproof as possible. 

When you’re looking for fireproof insulation and other building materials, it’s likely that you’ll see the terms ‘fire-retardant’ and ‘fire-resistant’ used, and it’s important to keep in mind the difference between the two:

  • Fire-resistant: this is used to describe materials that will continue to operate as normal during a fire, most likely due to the fact that they’ve been treated with substances to reinforce their fire-resistant properties
  • Fire-retardant: building materials described in this way have been designed in a way that helps to prevent flames from spreading during a fire

What Are The Best Types Of Fireproof Insulation?

All types of insulation will eventually become flammable under extreme temperatures, but some types of insulation are able to stop flames spreading more than others.

1. Fibreglass Insulation

Fibreglass insulation, also sometimes referred to as glass wool insulation, is a good, easy-to-install, energy-efficient option for insulating cavity walls, floors, and lofts. This type of insulation is made from very fine strands of glass that are woven into an insulating material, before a specially designed resin is applied as a bonding agent.

This means that fibreglass insulation has both moisture-resistant and fire-resistant properties, and it’s thought to be able to withstand temperatures of up to 1200°C, making it a relatively fireproof insulation option. Fibreglass insulation itself shouldn’t burn, but if it’s backed with paper or foil, this can be highly flammable in a fire, so this needs to be taken into account when you’re thinking about how fireproof your home is.

2. Spray Foam Insulation

Spray foam insulation is another good cavity wall insulation option, as it can be sprayed into wall cavities, where it expands and hardens to provide thermal - and often soundproof - insulation. Spray foam insulation has a high energy absorption rate, and it can even help to enhance the structural integrity of a property.

If you’re looking for fire-resistant spray foam insulation, Icynene® spray foam is regarded as a good option, as it has fire-retardant properties, which could help to reduce the rate of flames spreading. 

3. Cellulose Insulation

Cellulose insulation has a high R value and it contains fewer potential irritants than fibreglass insulation. As cellulose insulation is typically made from recycled paper sources, it can never be totally fireproof, but it can be treated with flame-retardant chemicals like boric acid and ammonium sulphate to increase its fire-resistant properties. The addition of boric acid also helps to reduce the risk of insulation mould, and of damage from insects.

4. Rockwool Insulation

Rockwool insulation, which is sometimes referred to as stone wool or mineral wool insulation, is non-combustible, but it can’t cope with quite the same levels of heat as some other types of insulation. However, rockwool insulation is often used alongside other types of insulation to improve its fireproof properties.

As it’s often made from mineral rock, rockwool insulation has an extremely high melting temperature, which is why many people choose this as a fireproof insulation material in their homes.

What Are The Best Fire-Resistant Building Materials?

Fireproof insulation isn’t the only fire-resistant building material you should consider using in your construction project. From bricks to slate and from sandstone to timber, here’s what you need to know about the fire-resistant properties of common building materials:

  • Bricks - as bricks are made in a fire kiln, they’re able to withstand extremely high levels of heat, and are thought to be fire-resistant up to temperatures of 1200°C
  • Steel - steel beams will buckle in a fire at around 600°C, but this construction material has a much higher melting point, of around 1400°C
  • Sandstone - sandstone is one of the most fire-resistant types of stone to use in construction. Sandstone is made from small mineral particles and fragments of rock, which make it highly durable
  • Slate - slate tiles are a brilliantly durable and non-combustible option if you’re looking for a fire-resistant building material for a roof
  • Timber - if timber is treated with chemicals such as sulphate, ammonium phosphate, or zinc chloride, it can be much more fire-resistant than other types of wood used in construction
  • Granite - granite can explode when it comes into contact with high levels of heat, so think carefully about where you’re intending to use this material in your building project
  • Concrete - as concrete quickly loses its strength in the face of fire, this is another building material that requires extra care if you’re thinking about using it in your home
  • Stucco plaster - stucco plaster can be a good fire-resistant finish for walls
  • Glass - windows crack and shatter under extreme heat, but double-glazed glass will take double the time to break in the event of a fire
  • Cork - if you’re looking for fire-resistant flooring materials, cork is a naturally fireproof option. When choosing a rug for your floor, opt for one with a shorter pile, as this will be more fire-resistant

Alongside fire-resistant building materials, it’s also important to research the fire-stopping and fire-protective materials you can use to improve how fireproof your home is. From thermal cavity closers to rockwool insulation sealant, explore our full range of fire-stopping building supplies. 

Other Ways To Fireproof Your Home

One of the most important ways to help fireproof your home is to install smoke alarms. The Irish Times’ analysis of Ireland’s house fire statistics found that smoke alarms were not present in almost 40% of fatal house fires from 2010-19, despite 90% of households claiming they have one.

Seán Hogan of the National Directorate of Fire and Emergency management team explained: “We have found the best of systems are put in, but people are taking them out because they are smoking indoors, doing cooking indoors, etc. It’s a mismatch between safety and lifestyle.

“Sometimes, people take out the battery because they are causing what is perceived to be a nuisance alarm and that’s generally to do with the alarm being in the wrong place.”

This demonstrates that it’s not enough just to have a smoke alarm; you need to test it regularly (ideally weekly), keep the batteries in it at all times, and make sure it’s not positioned too close to an appliance that might trigger it all of the time, such as the toaster.

Other ways to help fireproof your home include:

  • Make sure you have a fire extinguisher in your kitchen and that everyone in the house knows how to use it properly
  • Always be careful with candles around curtains, books, and soft furnishings
  • Ensure carpets and rugs are treated with flame-retardant chemicals to increase their fireproof properties
  • Keep your gutters clear of dry debris, such as leaves, to lower the risk of these catching fire in high temperatures. Make sure you discard any dry debris away from your home to further reduce the risk of fire
  • Have your chimney cleaned regularly to prevent a build-up of soot and flue
  • Keep your lawn well-watered to stop it from drying out and becoming more likely to burn in high temperatures

If you have any questions about the best fireproof insulation to use in your home or about any of our fire-protective building materials, please contact us here.