SA Roofing November 2018 // Issue 106 | Page 21

FEATURES The pre-requisite for an effective thatch fire retardant system is a good quality thatch layer with the correct compaction. condition of insurance cover in many risk assessments undertaken by insurance companies, and also become an insistence to local authorities when approving plans that do not meet the building regulations nationwide. I cannot stress enough the importance of validating the claims made by the company being selected to perform the fire protection application, and that the product is professionally manufactured along with the relevant testing by the proper authorities.” Another matter to consider says Heatlie is that municipal fire protection inspectors are not equipped, through site inspections, to identify what has been sprayed onto a thatched roof, or if it has been done effectively or not. Enlighten yourself When it comes to the use of chemicals on thatch, normally the following questions may be asked: do they test for public safety? Do they test for water stream? What is the effluent of the chemicals? Does it cause rotting of thatch? Are there any tests? Are they measured over a period of time? www.saroofing.co.za What determines that time frame? How long is it supposed to last? How long is the warranty? And so on. “These are questions that may have been asked, without receiving any answers,” says Kobus Strydom, FIRELAB owner. However, all these answers should be available from a manufacturer once a product or system has been evaluated correctly. Strydom further states that the pre-requisite for an effective thatch fire retardant system is a good quality thatch layer with the correct compaction to give the client the best possible protection. This process needs to be done according to specifications, using the correct material. The use of un-approved fire retardants can damage the properties of the thatch layer. With correct compaction, it will burn slower and will only smoulder in the absence of wind. If the compaction is correct, it will not burn out in minutes. Thatch grass layers, although compacted well, still have cavities between the thatch stems; if the pressure and the chemicals from the spray retardant are excessive, the chemical penetrates the thatch layer, making it hard. With natural thatch being elastic in nature, it could break if it’s hard during a severe hail storm. With breakage comes water leakage and further problems down the line. Fire retardant applicators spray the thatch inside and outside, and should an incorrect product be applied, this will stop the breathing capabilities of the thatch layer. The chemicals seal in the moisture which creates a build-up, causing it to rot overtime. Some products on the market glue the thatch together to prevent baboons from pulling it out, especially in game lodges. “You can’t do this because thatch needs to breathe. It’s glued together and then you have a rotting heap inside the roof – this costs thousands of rands to repair as the entire layer needs removing,” says Strydom. It is commonly shared that a thatched roof should be retreated with fire-retardant every five to seven years if the post- treatment option has been used. While it’s an expensive process, this may however be a requirement in terms of the NBR if the project is not planned correctly. CLADDING // CONCRETE // INSULATION // STEEL // THATCH // TIMBER // TRANSLUCENT // WATERPROOFING // COMPONENTS NOVEMBER 2018 19