Taking The Heat Off
The Age
Wednesday December 8, 2004
As with most things, preparation is the key to giving your house the best chance against a bushfire.
EVER since their close call with the Ash Wednesday fires of 1983, Trevor and Pam Miskin have been working to shore up their home against bushfire.These days - in what the Country Fire Authority see as a good example for others - their double-brick house at Wesburn in bushland east of Melbourne boasts a 90,000-litre underground water-tank, as well as a dam and electric and petrol pumps to bring the water to the house. They are now installing an external sprinkler system.The Miskins' efforts - which cost between $8000 and $10,000 - to minimise the chance of fire destroying their home were motivated largely by their experiences when the Ash Wednesday bushfires came within a kilometre of their previous house at nearby Hoddles Creek. They spent several nervous days without power and water connections and just a 5000-litre water-tank to fight the fire.Pam says: "It was a pretty scary time. We thought, 'Oh, I think we need to do a bit more for the next place."Fire authorities say that preparation is the key to saving your house.Amanda Leck, community development co-ordinator at the CFA, says that, while simple steps such as cleaning gutters ahead of summer each year help, they are not all that is involved. The issues involved include siting a new home so that it is not on a north or north-westerly facing slope and keeping rooflines simple, through to sealing gaps in the roof (and reducing the risk of ember penetration) and installing metal screens over vents and windows.Some of these issues, such as building on a concrete slab instead of having a house raised on stumps and ensuring all above-ground water and gas pipes are made from metal, are required for new homes being built in fire-prone areas under the Building Code of Australia and an Australian Standard on buildings in bushfire-prone areas but there is no obligation for older properties to be retrospectively outfitted.A recent development is the installation of external sprinkler systems such as that being used by the Miskins.Usually on the roof, these consist of spray heads, a pump and pipes connecting the system to a water source, preferably not the mains water supply because pressure may be significantly reduced as firefighters and other residents draw heavily on it. They can be manually activated or an automated system may be triggered by such devices as thermal sensors near vegetation. There are also remote activation possibilities using a mobile phone.The CFA says that external sprinkler systems should be only one part of a strategy to combat bushfires. "Our key message is not to rely on them," says Leck.Internal sprinklers are useful in combating fires such as those caused by faulty wiring or electrical appliances. "The domestic sprinkler system is the next generation, if you like, of residential asset and life protection," says David Nicholson, director of community safety at the Metropolitan Fire Brigade, which is called to about 1800 house fires a year.Nicholson says a review of the standard for the use of sprinklers in houses - which may allow certain rooms to be excluded from the system; for them to be installed by trained plumbers; and for them to be fed directly from existing water piping - could see systems installed for as little as $1000 to $1500.He says these systems, which are mandatory in some US states, are very effective. "In America there hasn't been a life lost in a home that's had a properly installed and maintained domestic sprinkler system." The Miskins, meanwhile, say they won't rest comfortably this summer despite their preparations. "You never rest comfortably," says Pam. "I always start to feel sick whenever summer comes around. The first total fire ban day and I start to get twitchy."External forcesYour garden can help you survive a bushfire.People are going bush again. Bush blocks are being snapped up on all sides of the city - as weekenders or by those able to work from home, retirees, or people willing to commute.Before the next fire ruins people's enthusiasm for the bush (and their homes and belongings), it's time to think about the garden and what it can do to help prevent damage.After the wet winter that some areas have had, vegetation will grow vigorously during spring and, in summer, will dry off, leaving plenty of fuel for fires.A new book, Landscape and Building Design for Bushfire Areas, by Caird Ramsay and Lisle Rudolph (published by CSIRO Publishing, rrp $39.95), is excellent for anyone about to build in a fire-prone area.The authors refute the idea that bushfires are so bad there is no stopping them and no point being prepared. Buildings and their surrounds can be designed to improve the chances of survival, they say.Fire spreads three ways: embers and burning debris carried by the wind; heat radiation from the fire; and direct flame contact.Usually embers and burning debris are what start the fire in buildings. A fire's front passes in minutes but wind-driven burning debris could whirl around for hours.The authors say that plans for developments in fire-prone areas should begin with the landscape design before the building design.Four basic principles guide building design: minimise litter and ember accumulation points; minimise use of combustible materials externally; prevent entry of embers and burning debris driven by the wind; and provide and maintain firefighting services (such as water supply, emergency water storage, pumping and power).The landscape design principles aim to manage vegetation and provide barriers.We need to design landscapes in fire-prone areas with low-flammable plants as barriers, create large gaps between groups of trees (to slow the spread of fire) and a clear space around the buildings.Lower branches (up to two metres above the ground) and loose bark should be removed to slow the upward spread of a fire. The understorey should be kept clear of loose litter, as this catches fire and often becomes airborne.Dense foliage plants make good barriers but a plant's attributes should also be considered. For example, plants with a high volatile-oil content are very flammable, and those with leaves with a high moisture content are less flammable. Narrow leaves catch fire more readily, and many native plants are good fire retardants.A surprising number of trees are suitable. Hymenosporum flavum (native Frangipani) has lush foliage, which makes it a low-fire-risk tree. Some are even fire retardant, including Acacia dealbata, Acacia melanoxylon (Blackwood), and Atherosperma moschatum (southern sassifras).Many banksias, such as Banksia marginata and Banksia spinulosa also make the low-fire-risk list, which was supplied by Kuranga Native Nursery (9879 4076).Frances Saunders, horticulturist and landscape designerBushfire survival guides? The Australian Bushfire Safety Guide: The Essential Survival Guide for Every Home, John Schauble (HarperCollins, 2004)The work of CFA volunteer and senior Age journalist John Schauble, this 198-page guide looks at the steps owners need to take to maximise the chance of their house surviving a bushfire. Schauble covers everything from the correct siting of a home and construction requirements through to what sort of vegetation to plant around the home, as well as information on bushfire behaviour and what to do in a bushfire.? The Complete Bushfire Safety Book, Joan Webster, (Random House Australia, 2000) and Essential Bushfire Safety Tips, Joan Webster (Random House Australia, 2001)The Complete Bushfire Safety Book is a comprehensive guide with chapters on choosing a safe site, safe property layouts, designing homes to keep out fires, facilities for defence and planting for bushfire protection, while Essential Bushfire Safety Tips is a quick reference guide containing the essence of the latter. See bushfiresafety.com? Living in the Bush (Country Fire Authority, new edition, October 2004)Described as a "bushfire survival plan workbook", it contains sections on identifying whether your home is at risk, how to prepare your home for a bushfire and what to do during a bushfire, as well as a survival plan worksheet. The workbook can be downloaded from http://www.cfa.vic.gov.au/residents/living/litb-workbook.htm or call 1800 240 667.
© 2004 The Age
