Fire Safety

Thatch and Fire Safety

The reason for using Magma Firestop® fire retardant spray on thatched roofs is for fire safety.

Magma Firestop® reduces the risk of a fire being started by sparks and embers, the main proven cause of thatch fires.  This is so important as once alight, thatch fires are notoriously difficult to extinguish and can result in considerable loss; often of our irreplaceable heritage buildings (the majority of thatched buildings are listed).

Magma Firestop and Fires Safety 6

The Causes of Thatch Fire

Have a look at the Forensic Investigators report (Burgoynes) on the causes of thatch fires. This identifies 66% of the fires they investigated as being due to ejected embers from the chimney.

Magma Firestop® addresses the risks of ejected embers. Download the report and make an informed choice on your property.

“Again, the correlation between thatch fires and solid fuel stoves with liners and low chimneys was demonstrated, together with a short time between lighting and discovery. There was also a notable correlation with dry conditions and evidence that bird guards and spark arrestors do not necessarily prevent thatch fires.  Furthermore, there was a correlation between dry weather and thatch fires. It further supports the view that the majority of fires associated with chimneys arise from ejected embers, often generated during lighting the fire, rather than defects in chimneys or heat conducted through the structure.”

Magma Firestop and Fire Safety 4 - Burnt thatch

FPA Research

Historic England and the NFU Mutual then funded research at the Fire Protection Association (FPA) which furthered Burgoynes excellent work by looking into thatch fires and woodburners.  This extensive and comprehensive research not only confirmed embers as a proven cause of thatch fires it also identified that, with regard to the old heat transfer (by conduction) theory, “the historic work appears to have utilised inputs that we now know to be unrepresentative of reality”.   Read more on this research

FPA logo re thatch fire safety research

Historic England Logo - Thatch Fire Safety

NFU Mutual logo - Magma Thatch Fire Safety

There is a need to reduce this risk of embers from chimneys catching thatched roofs on fire.

This is where Magma Firestop® is beneficial.

Reducing the Risk of Thatch Fire

The Thatch Advice Centre have extensive knowledge and understanding of thatch, thatch fires, building regulations, fire tests and more.  They have produced an up to date Thatch Fire Safety leaflet  which incorporates Burgoynes and FPA information (with their knowledge and approval) along with other useful and sensible advice.  It is an essential read for anyone with a thatched property.

Magma Thatch Fire Safety Thatch Advice Centre logo

Have a look at the Thatch Advice Centre Fire Safety Leaflet for up to date advice on what you can do to improve the fire safety of your thatched property.

Many owners of thatched properties with working chimneys still want to heat their homes using solid fuel and remain insured. This is where Magma Firestop® can help in reducing the main proven risk and also in achieving appropriate insurance cover.

The FPA have released Guidance which, in line with some insurers, starts with recommending that no woodburners are used.  It then goes on to identify ways to improve thatch fire safety if woodburners are used in thatched properties.

Relevant Documents to help you Understand the Thatch Fire Causes, Risks and how to reduce them.

Another area where Magma Firestop® is helpful in reducing the thatch fire risk, is where the chimney is lower than the 1.8m recommended in building regulations. One way to reduce the risk of any ejected embers causing a fire on the thatch is to use Magma Firestop® fire retardant spray.  Increasing chimney height is also recommended as another way to improve fire safety but as listed building consent is required to increase the height it is not always easy.   These two measures combined or individually are often required by insurers as part of risk reduction measures for those using woodburners/multifuel stoves or even open fires.

Most thatched properties are individual and therefore we recommend that the fire risk is assessed as such, often the fire service can help with this.

How Magma Firestop® works to improve fire safety

The effect of Magma Firestop® is:-

  • Withdraws energy from the environment (temperature drops)
  • Non-toxic gasses prevent oxygen reaching the combustion zone, interrupting the spread of flame.
  • Faster carbonisation will isolate the material (fuel) from the ignition source

Magma Firestop® fire retardant spray is a coating on the thatch which, when exposed to embers, interrupts the ability of fire to spread by creating a protective char.

Magma Fires Safety - fire triangle

Best practice

An easy answer to best practice is to avoid using a woodburner/fire but is that realistic.  We know that a lot of people need to heat their homes and also have done so very successfully for many years – often with the added protection of Magma Firestop®.

It is also simple to say don’t have bonfires close to the thatch and keep away from external fire sources such as fireworks, Chinese lanterns or barbeques.  This sounds manageable but is, in practice, not so straightforward, as thatched cottages have neighbours; things outside can also catch fire and spread to thatch.

There are risks with many things in life; for example driving a car.  By using your seatbelt, checking the tyres and brakes and reducing the known risk factors you acknowledge that you have done your best and have peace of mind.  Similarly, best practice with a thatched property is to assess the fire risks to your property and reduce them.  Magma Firestop® is very useful part of the arsenal of thatch fire safety measures to help prevent thatch fires and give that peace of mind.

Magma Firestop® and Thatch Insurance

Any measures taken to reduce the risk of thatch fire are beneficial in terms of your peace of mind but can also help with your thatch insurance. There are many specialist insurers for thatch who offer reduced premiums for those who can show that they are reducing the risk. Owners of thatch with Magma Firestop® applied by approved sprayers are provided with a Treatment Certificate to show to insurers.

Here is an example of a Magma Firestop® Treatment Certificate

Thatch properties are no more likely to catch fire than other properties. The problem is that if they do, their fires are notoriously hard to put out because the thatch is designed to repel water.   This can be very costly in terms of loss of property and insurance premiums. The benefit of Magma Firestop® is that the spray is specifically designed to help prevent thatch fires.

Thatch – Safe Model Plus

Using Thatch Safe® fire resisting barrier over the rafters and then spraying the thatch with Magma Firestop®, gives the Thatch-Safe Model Plus.

As we can see from the diagram, the thatch has all the benefits of the THATCH-SAFE® and the Magma Firestop®. This treatment to the exterior of the thatch gives an A rating for spread of flame. This means it gives added protection in the event of an external fire hazard eg embers.

Roofs treated with the Thatch-Safe Fire Resisting Barrier and Magma Firestop® Fire Retardant Spray can benefit from reduced insurance premiums.

For more help with any aspect of this site or the Magma Firestop® and Thatch-Safe® products please contact us.

Magma Fires Safety - Thatch Safe Model Plus Diagram