{"id":29848,"date":"2025-11-03T15:19:24","date_gmt":"2025-11-03T05:19:24","guid":{"rendered":"https:\/\/woodcentral.com.au\/?p=29848"},"modified":"2025-11-03T15:19:27","modified_gmt":"2025-11-03T05:19:27","slug":"wind-tested-plywood-bracing-proves-its-worth-against-cyclones","status":"publish","type":"post","link":"https:\/\/woodcentral.com.au\/wind-tested-plywood-bracing-proves-its-worth-against-cyclones\/","title":{"rendered":"Wind-Tested: Plywood Bracing Proves Its Worth Against Cyclones"},"content":{"rendered":"\n<p><em>Tropical cyclone Alessia blew in to the Kimberley coast 12 years ago on\u00a0November 22\u00a0and just as quickly fizzled out. <strong>This 2013 flashback report <\/strong>by\u00a0senior editor Jim Bowden\u00a0found that although it\u2019s a regular activity in the Brisbane laboratories of the Engineered Wood Products Association of Australasia, wind load testing on plywood sheeting was in full swing<\/em>.<\/p>\n\n\n\n<figure class=\"wp-block-image size-full\"><a href=\"https:\/\/kennedystimbers.com.au\/\"><img loading=\"lazy\" decoding=\"async\" width=\"640\" height=\"160\" src=\"https:\/\/woodcentral.b-cdn.net\/wp-content\/uploads\/2024\/07\/KennedysAd.png.webp\" alt=\"KennedysAd\" class=\"wp-image-19320\" srcset=\"https:\/\/woodcentral.com.au\/wp-content\/uploads\/2024\/07\/KennedysAd.png 640w, https:\/\/woodcentral.com.au\/wp-content\/uploads\/2024\/07\/KennedysAd-300x75.png 300w, https:\/\/woodcentral.com.au\/wp-content\/uploads\/2024\/07\/KennedysAd-600x150.png 600w\" sizes=\"auto, (max-width: 640px) 100vw, 640px\" \/><\/a><\/figure>\n\n\n\n<p>Fears of another Yasi were allayed. That cyclone, which crossed the Queensland coast on February 3, 2011, brought a Category 5 storm more than 600 km wide with 95 km \/ hour winds battering towns along a 350-km strip from Cairns to Townsville.<\/p>\n\n\n\n<p>Crews from the cyclone testing station at&nbsp;James Cook University reported very few structural failures in timber buildings built to \u2018modern\u2019 building codes and plywood bracings stood their ground against Yasi\u2019s massive wind surge.<\/p>\n\n\n\n<p>\u2018Tis the season to be merry \u2013 and \u2018tis the season for cyclone and severe windstorms,\u201d reflected the author.<\/p>\n\n\n\n<p>Australia&#8217;s cyclone season runs from November 1 to April 30, with an average of 9 to 11 cyclones forming each year, and the potential for severe cyclones is higher than usual due to warmer ocean temperatures.<\/p>\n\n\n\n<p>On that November day 12 years ago, heavy\u00a0thuds came down the line as we spoke with EWPAA General Manager Simon Dorries.<\/p>\n\n\n\n<p>\u201cDon\u2019t worry, we\u2019re impact testing for wind loads,\u201d he assured us.<\/p>\n\n\n\n<p>We found laboratory technician Andrew McLaughlin lifting a 20 kg weight into the top end of a tall cylinder positioned by consulting engineer James MacGregor on a plywood panel.<\/p>\n\n\n\n<p>Whoosh, thud \u2026 and another plywood product from an EWPAA member passed the impact test for cyclone shelter construction.<\/p>\n\n\n\n<p>The tests simulate the effects of flying debris at different impact speeds in a windstorm.<\/p>\n\n\n\n<p>\u201cBuilding and construction in cyclone-prone areas requires materials designed to protect against high-wind impact conditions,\u201d MacGregor said.<\/p>\n\n\n\n<p>\u201cEWPAA structural plywood is designed for such conditions and constantly passes flying debris testing with flying colours,\u201d he said.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1600\" height=\"1199\" src=\"https:\/\/woodcentral.b-cdn.net\/wp-content\/uploads\/2025\/11\/image002-87.jpg\" alt=\"image002 (87)\" class=\"wp-image-29849\" srcset=\"https:\/\/woodcentral.com.au\/wp-content\/uploads\/2025\/11\/image002-87.jpg 1600w, https:\/\/woodcentral.com.au\/wp-content\/uploads\/2025\/11\/image002-87-300x225.jpg 300w, https:\/\/woodcentral.com.au\/wp-content\/uploads\/2025\/11\/image002-87-1024x767.jpg 1024w, https:\/\/woodcentral.com.au\/wp-content\/uploads\/2025\/11\/image002-87-768x576.jpg 768w, https:\/\/woodcentral.com.au\/wp-content\/uploads\/2025\/11\/image002-87-1536x1151.jpg 1536w, https:\/\/woodcentral.com.au\/wp-content\/uploads\/2025\/11\/image002-87-560x420.jpg 560w, https:\/\/woodcentral.com.au\/wp-content\/uploads\/2025\/11\/image002-87-80x60.jpg 80w, https:\/\/woodcentral.com.au\/wp-content\/uploads\/2025\/11\/image002-87-696x522.jpg 696w, https:\/\/woodcentral.com.au\/wp-content\/uploads\/2025\/11\/image002-87-1068x800.jpg 1068w, https:\/\/woodcentral.com.au\/wp-content\/uploads\/2025\/11\/image002-87-265x198.jpg 265w\" sizes=\"auto, (max-width: 1600px) 100vw, 1600px\" \/><figcaption class=\"wp-element-caption\">Plywood bracing 2745 x 1200 x 7 mm (Photo credit: Canterbury Timber)<\/figcaption><\/figure>\n\n\n\n<p>The plywood for cyclone shelters must resist wind load requirements specified in AS\/NZS standard 1170.2, a joint standard for structural design and wind actions.<\/p>\n\n\n\n<p>MacGregor said plywood offered all the&nbsp;inherent advantages of the parent wood plus enhanced properties in its laminated structure.<\/p>\n\n\n\n<p>\u201cBeing a wood-based material, plywood has the ability to accommodate the occasional short-term overload at up to twice the design load,\u201d MacGregor continued.<\/p>\n\n\n\n<p>\u201cThis is essential in cyclonic winds or seismic activity. This property is also effective when used as construction flooring or as concrete formwork. Plywood&#8217;s laminated structure distributes loads from impact over a larger area on the opposite face, which effectively reduces the tensile stress.\u201d<\/p>\n\n\n\n<p>Simon Dorries said timber\u00a0strength designs and connections were constantly changing, and engineered wood products were continuously tested in EWPAA laboratories.<\/p>\n\n\n\n<p>He said wind and earthquakes continued to impact on low-rise buildings in Australia and New Zealand. Structural plywood provided a reliable means to brace these building frames in accordance with AS1684 (residential timber frame construction), a four-part standard covering design criteria, building practices, tie-downs, bracing and span tables for timber framing members.<\/p>\n\n\n\n<p>EWPAA structural products are third-party audited under a JAS-ANZ accredited product certification scheme, an industry-wide certification based on International Organisation for Standardisation (ISO) requirements.<\/p>\n\n\n\n<p>This system requires that a production facility maintain a documented process control system, conduct in-mill end-product testing and have rigorous internal audit procedures.<\/p>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Tropical cyclone Alessia blew in to the Kimberley coast 12 years ago on\u00a0November 22\u00a0and just as quickly fizzled out. This 2013 flashback report by\u00a0senior editor Jim Bowden\u00a0found that although it\u2019s a regular activity in the Brisbane laboratories of the Engineered Wood Products Association of Australasia, wind load testing on plywood sheeting was in full swing. [&hellip;]<\/p>\n","protected":false},"author":17,"featured_media":29850,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":"","_wpscppro_dont_share_socialmedia":false,"_wpscppro_custom_social_share_image":0,"_facebook_share_type":"default","_twitter_share_type":"default","_linkedin_share_type":"default","_pinterest_share_type":"default","_linkedin_share_type_page":"default","_instagram_share_type":"default","_medium_share_type":"default","_threads_share_type":"default","_google_business_share_type":"default","_selected_social_profile":[],"_wpsp_enable_custom_social_template":false,"_wpsp_social_scheduling":{"enabled":false,"datetime":null,"platforms":[],"status":"template_only","dateOption":"today","timeOption":"now","customDays":"","customHours":"","customDate":"","customTime":"","schedulingType":"absolute"},"_wpsp_active_default_template":true},"categories":[50,37,185,39,85,84,54,82],"tags":[],"ppma_author":[91],"class_list":{"0":"post-29848","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-australia","8":"category-building-and-construction","9":"category-flashback","10":"category-mass-timber","11":"category-new-south-wales","12":"category-northern-territory","13":"category-queensland","14":"category-western-australia"},"authors":[{"term_id":91,"user_id":17,"is_guest":0,"slug":"jim-bowden","display_name":"Jim Bowden","avatar_url":{"url":"https:\/\/woodcentral.com.au\/wp-content\/uploads\/2023\/01\/J-Bowden-headshot-3-scaled.jpeg","url2x":"https:\/\/woodcentral.com.au\/wp-content\/uploads\/2023\/01\/J-Bowden-headshot-3-scaled.jpeg"},"0":null,"1":"","2":"","3":"","4":"","5":"","6":"","7":"","8":""}],"_links":{"self":[{"href":"https:\/\/woodcentral.com.au\/wp-json\/wp\/v2\/posts\/29848","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/woodcentral.com.au\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/woodcentral.com.au\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/woodcentral.com.au\/wp-json\/wp\/v2\/users\/17"}],"replies":[{"embeddable":true,"href":"https:\/\/woodcentral.com.au\/wp-json\/wp\/v2\/comments?post=29848"}],"version-history":[{"count":2,"href":"https:\/\/woodcentral.com.au\/wp-json\/wp\/v2\/posts\/29848\/revisions"}],"predecessor-version":[{"id":29852,"href":"https:\/\/woodcentral.com.au\/wp-json\/wp\/v2\/posts\/29848\/revisions\/29852"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/woodcentral.com.au\/wp-json\/wp\/v2\/media\/29850"}],"wp:attachment":[{"href":"https:\/\/woodcentral.com.au\/wp-json\/wp\/v2\/media?parent=29848"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/woodcentral.com.au\/wp-json\/wp\/v2\/categories?post=29848"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/woodcentral.com.au\/wp-json\/wp\/v2\/tags?post=29848"},{"taxonomy":"author","embeddable":true,"href":"https:\/\/woodcentral.com.au\/wp-json\/wp\/v2\/ppma_author?post=29848"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}