Johannesburg - One of the best ways of preventing galloping thatch roof fires is to install a dedicated drencher water system at the highest part of the roof, an expert said on Tuesday.
Fire Protection Association of Southern Africa board director Marcel Wood was commenting after a fire destroyed 76 homes in St Francis Bay, in the Eastern Cape, many of them with thatch roofs.
Wood said the cause of the fire could turn out to be a combination of factors.
“Investigators are trying to assess the cause, which may turn out to be an unfortunate combination of high winds, the open flames of a braai or an overheated chimney without the defensive surround required in today’s bylaws,” he said.
The damage in St Francis Bay has been estimated at R100 million.
Wood said thatch presented a higher risk of fire than other roofing materials and that special precautions needed to be taken.
Common ignition sources for thatch fires included electrical faults, hot chimneys passing through thatch, lightning and power surges.
On rare occasions, the embers from the open flames of a bonfire or braai could be blown onto a highly combustible substance such as dried trees, wood piles or thatched roofs.
A dedicated drencher water system could cascade water over and down all of the exposed thatch in the event of a fire.
While this might not save the immediate property involved, it could prevent or minimise the destruction of multiple properties.
“If one can keep the thatch wet or cool in the first instance, it limits the effects of radiated heat as well as cools or wets embers that are deposited on neighbouring thatch roofs which “struggle” to set alight wet or cooled thatch.” - Sapa