How to protect a thatched roofComment on this story
I watched with horror the fire that destroyed many homes in St Francis Bay in the Eastern Cape recently. I live in a thatched home. What fire precautions can I take?
Marcel Wood of Risk Management at Etana Insurance has this advice:
“The fire spread through neighbouring thatch-roofed homes fanned by strong winds. Thatch in its simplest form is a dried type of grass interwoven to form a strong roofing material which is popular in holiday homes and delivers three main advantages: individualistic décor, superb insulation in all seasons and, compared with tile roofing, is comparatively cheap.”
But thatch presents a higher risk of fire than other roofing
Wood explains that common ignition sources for thatch fires include electrical faults, hot chimneys passing through thatch, lightning and power surges and, on rare occasions, the embers from open flames of a bonfire or braai can be blown on to a highly combustible substance such as a dry tree, a wood pile - or a thatched roof.
How to deal with problems?
* Electrical faults – require vigilant and regular maintenance.
* Hot chimneys passing through the thatch roof – require purpose designed protective linings
* Lightning and power surges – effective surge protection devices are available for domestic and business premises. These work better than lightning protection rods and more importantly protect electronic equipment during power interruptions caused by power surges and lightning.
How thatch fires spread?
According to Wood, a “fire front” is the portion sustaining continuous flaming combustion. As the front approaches, the fire heats both the surrounding air and woody materials – for example, the thatch roof adjacent to the one on fire.
It may also spread as winds carry hot embers and other burning materials through the air over roads, etc that may otherwise act as firebreaks. It follows, in areas with multiple thatch roofs, that embers set alight neighbouring properties downwind from the fire.
It also follows then that the best method to prevent the spread of fires between thatched roof houses in a suburb is the application of water which cools the thatch below its combustion /ignition temperature. Possibly, the best method to prevent this type of disaster happening is to have a dedicated drencher water system installed at the highest part of the roof, which can cascade water over and down all of the exposed thatch.
How prone are thatch-roof homes to fires?
Thatch-roofed properties are certainly more prone to fire than what is commonly termed “standard” construction in the insurance industry.
Thatch risks are insurable, but need to meet some specific risk management criteria to be insured.
* Wood is also board director of the Fire Protection Association of Southern Africa; SAIA board member, Environment and Social; SAIA Steering Committee: Strategic Risk Forum; SAIA Strategic Risk Forum Committee; and Chairman of the SAIA Fire Services Investigation Committee. - Saturday Star