Table 6.7 Assessment of in-line post materials – Assessment factors In-line post material Criteria Item Concrete Treated pine Recycled plastic Steel pipe Red gum Star pickets Construction Cost Relatively inexpensive Relatively inexpensive More expensive More expensive More expensive Relatively inexpensive and more difficult to More expensive for source longer/stronger pickets (can be twice the cost) Handling Heavy to handle Relatively light to to handle Relatively light to to handle Less bulky than timber, handle handle concrete and pipe Installation Can be installed quickly Requires no machinery to (e.g. driven by hand or install machine) Durability Rot and termite Termite-proof Can rot and/or be Rot- and Termite-proof Relatively rot- and Termite-proof by termites if not termite-proof attack treated Can be treated to make it last longer Rust Reinforcement can Rustproof Can rust and/or corrode Can corrode (although a corrode in wet, acidic or (the risk is higher in hot-dipped galvanised areas coastal, wet, acidic or coating makes posts salty areas) suitable for use in mediumly to highly Can be galvanised to corrosive environments prevent rusting (but that is more expensive) Resistance to Fire Can be affected by fire Easily burnt by Good in high-fire-risk Easily by natural disasters (e.g. they can lose bushfire areas as they provide bushfire structural integrity in a some resilience against hotter fire) fire, although a hotter fire will damage the galvanised coating Flood Can be brittle and prone Can warp, or split Can bend over during to damage if struck by over time floods large logs during floods Very buoyant and Some longer and stronger have been known to pickets are available that float out of the ground can resist higher pressures in deep floodwaters
Table 6.7 – Assessment of in-line post materials Assessment factors In-line post material Criteria Item Concrete Treated pine Recycled plastic Steel pipe Red gum Star pickets Construction Cost Relatively inexpensive Relatively inexpensive More expensive More expensive More expensive and more difficult to source Relatively inexpensive More expensive for longer/stronger pickets (can be twice the cost) Handling Heavy to handle Relatively light to handle to handle Relatively light to handle to handle Less bulky than timber, concrete and pipe Installation Can be installed quickly (e.g. driven by hand or machine) Requires no machinery to install Durability Rot and termite attack Termite-proof Can rot and/or be by termites if not treated Can be treated to make it last longer Rot- and Termite-proof Relatively rot- and termite-proof Termite-proof Rust Reinforcement can corrode in wet, acidic or areas Rustproof Can rust and/or corrode (the risk is higher in coastal, wet, acidic or salty areas) Can be galvanised to prevent rusting (but that is more expensive) Can corrode (although a hot-dipped galvanised coating makes posts suitable for use in mediumly to highly corrosive environments Resistance to natural disasters Fire Can be affected by fire (e.g. they can lose structural integrity in a hotter fire) Easily burnt by bushfire Good in high-fire-risk areas as they provide some resilience against fire, although a hotter fire will damage the galvanised coating Easily by bushfire Flood Can be brittle and prone to damage if struck by large logs during floods Can warp, or split over time Very buoyant and have been known to float out of the ground in deep floodwaters Can bend over during floods Some longer and stronger pickets are available that can resist higher pressures