{"id":6452,"date":"2026-02-03T18:25:24","date_gmt":"2026-02-03T18:25:24","guid":{"rendered":"https:\/\/www.millboard.com\/en-gb\/?page_id=5877"},"modified":"2026-03-09T19:23:43","modified_gmt":"2026-03-09T19:23:43","slug":"duospan","status":"publish","type":"page","link":"https:\/\/www.millboard.com\/en-us\/composite-decking-collections\/decking-subframes\/duospan\/","title":{"rendered":"DuoSpan"},"content":{"rendered":"<header class=\"page-header wp-block alignfull has-brand-1-background-color has-background page-header--type--page has-breadcrumbs\">\n    <div class=\"page-header__inner\">\n                    <!-- Breadcrumbs -->\n            <div class=\"page-header__breadcrumbs\">\n                <nav class=\"breadcrumbs\">\n    <span class=\"breadcrumbs__yoast-wrapper\"><span><a href=\"https:\/\/www.millboard.com\/en-us\/\">Home<\/a><\/span><\/span><\/nav>\n            <\/div>\n        \n        <div class=\"page-header__wrapper\">\n            <div class=\"page-header__image-wrapper\">\n                                    <div class=\"page-header__image\">\n                        <div class=\"page-header__image-inner img-fit\">\n                            <img decoding=\"async\" width=\"768\" height=\"1152\" src=\"https:\/\/www.millboard.com\/en-us\/wp-content\/uploads\/sites\/5\/2026\/02\/DuoSpan_Installation-Image-13-768x1152.jpg\" class=\"\" alt=\"\" fetchpriority=\"high\" data-spai-eager=\"1\" role=\"presentation\" loading=\"eager\" srcset=\"https:\/\/www.millboard.com\/en-us\/wp-content\/uploads\/sites\/5\/2026\/02\/DuoSpan_Installation-Image-13-768x1152.jpg 768w, https:\/\/www.millboard.com\/en-us\/wp-content\/uploads\/sites\/5\/2026\/02\/DuoSpan_Installation-Image-13-200x300.jpg 200w, https:\/\/www.millboard.com\/en-us\/wp-content\/uploads\/sites\/5\/2026\/02\/DuoSpan_Installation-Image-13-683x1024.jpg 683w, https:\/\/www.millboard.com\/en-us\/wp-content\/uploads\/sites\/5\/2026\/02\/DuoSpan_Installation-Image-13-1050x1575.jpg 1050w, https:\/\/www.millboard.com\/en-us\/wp-content\/uploads\/sites\/5\/2026\/02\/DuoSpan_Installation-Image-13-600x900.jpg 600w, https:\/\/www.millboard.com\/en-us\/wp-content\/uploads\/sites\/5\/2026\/02\/DuoSpan_Installation-Image-13.jpg 1365w\" sizes=\"(max-width: 768px) 100vw, 768px\" \/>                        <\/div>\n                    <\/div>\n                            <\/div>\n\n            <div class=\"page-header__content page-header__content--first\">\n                <div class=\"page-header__header\">\n                    \n                                            <h1 class=\"page-header__heading is-style-typestyle-h1\">DuoSpan<\/h1>\n                                    <\/div>\n\n                            <\/div>\n                <div class=\"page-header__content page-header__content--last\">\n                                                <div class=\"page-header__description\">\n                        <p>Millboard DuoSpan\u00ae combines the strength of aluminium with the design flexibility of recycled plastic. This achieves a lightweight system that provides exceptional ease of installation, enormous strength and durability, and the scope to construct stunning decks and structures that would be impossible with conventional subframes.<\/p>\n                    <\/div>\n                \n                \n                            <\/div>\n        <\/div>\n    <\/div>\n\n    <\/header>\n\n    <div class=\"woocommerce-notices-wrapper\"><\/div>\n\n<div data-link=\"false\" class=\"media-object media-content wp-block alignfull\" data-media=\"image\" data-media-type=\"image\" data-media-position=\"after\" data-orientation=\"horizontal\">\n    <div class=\"media-object__inner\">\n        \n        <div class=\"media-object__content flex-column\">\n            \n            \n                            <div class=\"media-object__header flex-column\">\n                                            <h2 id=\"designed-to-do-more\" class=\"media-object__heading\">Designed to do more<\/h2>\n                    \n                                             <div class=\"media-object__subheading\">\n                            <p>DuoSpan\u00ae provides the perfect subframe for Millboard decking, as well as a universal support system for other outdoor flooring. Its ingenious design facilitates top-down fixing of www.millboard.composite decking boards and makes it an easy installation for all levels of competence, no matter the complexity of the decking project.<\/p>\n<p>DuoSpan\u00ae has been designed by industry professionals to comply with Eurocode 1: Actions on Structures (BS EN 1991-1-1), and is available in component form.<\/p>\n<p>With other solutions the profiles aren\u2019t always rigid and straight, leading to numerous noggins being required to help in the installation, whereas with DuoSpan the aluminium joists and beams are almost perfectly straight, resulting in a faster install.<\/p>\n                        <\/div>\n                     \n                                    <\/div>\n            \n            \n            \n                    <\/div>\n\n                    <div class=\"media-object__media media-object__media--image  img-fit\">\n                                    <img decoding=\"async\" width=\"768\" height=\"512\" src=\"https:\/\/www.millboard.com\/en-us\/wp-content\/uploads\/sites\/5\/2026\/02\/DuoSpan_Installation-Image-12-768x512.jpg\" class=\"\" alt=\"\" role=\"presentation\" loading=\"lazy\" srcset=\"https:\/\/www.millboard.com\/en-us\/wp-content\/uploads\/sites\/5\/2026\/02\/DuoSpan_Installation-Image-12-768x512.jpg 768w, https:\/\/www.millboard.com\/en-us\/wp-content\/uploads\/sites\/5\/2026\/02\/DuoSpan_Installation-Image-12-300x200.jpg 300w, https:\/\/www.millboard.com\/en-us\/wp-content\/uploads\/sites\/5\/2026\/02\/DuoSpan_Installation-Image-12-1024x683.jpg 1024w, https:\/\/www.millboard.com\/en-us\/wp-content\/uploads\/sites\/5\/2026\/02\/DuoSpan_Installation-Image-12-600x400.jpg 600w, https:\/\/www.millboard.com\/en-us\/wp-content\/uploads\/sites\/5\/2026\/02\/DuoSpan_Installation-Image-12.jpg 2048w\" sizes=\"auto, (max-width: 768px) 100vw, 768px\" \/>                            <\/div>\n            <\/div>\n\n<\/div>\n\n\n<div class=\"navigation-tiles wp-block alignfull\">\n    <div class=\"navigation-tiles__inner\">\n                    <div class=\"navigation-tiles__header\">\n                                \n                                    <h2 id=\"duospan-products\" class=\"navigation-tiles__heading\">\n                        DuoSpan\u00ae Products                    <\/h2>\n                            <\/div>\n        \n                    <div class=\"navigation-tiles__tiles\">\n                                    <div class=\"navigation-tiles__tile\">\n                                                    <h3 class=\"navigation-tiles__tile-title\">\n                                DuoSpan 51 \u2013 90 Degree Bracket Kit Box of 10 sets                            <\/h3>\n                                                \n                                                \n                                                    <a target=\"\" rel=\"\" href=\"https:\/\/www.millboard.com\/en-us\/shop\/composite-decking\/duospan-51-90-degree-bracket-kit-box-of-10-sets\/\" class=\"navigation-tiles__tile-cta g-button\">View Product<\/a>\n                                            <\/div>\n                                    <div class=\"navigation-tiles__tile\">\n                                                    <h3 class=\"navigation-tiles__tile-title\">\n                                DuoSpan 51 Flexible Bracket Kit Box of 10 sets                            <\/h3>\n                                                \n                                                \n                                                    <a target=\"\" rel=\"\" href=\"https:\/\/www.millboard.com\/en-us\/shop\/composite-decking\/duospan-51-flexible-bracket-kit-box-of-10-sets\/\" class=\"navigation-tiles__tile-cta g-button\">View Product<\/a>\n                                            <\/div>\n                                    <div class=\"navigation-tiles__tile\">\n                                                    <h3 class=\"navigation-tiles__tile-title\">\n                                DuoSpan 51 Joist Aluminium                            <\/h3>\n                                                \n                                                \n                                                    <a target=\"\" rel=\"\" href=\"https:\/\/www.millboard.com\/en-us\/shop\/composite-decking\/duospan-51-joist-aluminium\/\" class=\"navigation-tiles__tile-cta g-button\">View Product<\/a>\n                                            <\/div>\n                                    <div class=\"navigation-tiles__tile\">\n                                                    <h3 class=\"navigation-tiles__tile-title\">\n                                DuoSpan 51 Straight Connector Kit Box of 10 sets                            <\/h3>\n                                                \n                                                \n                                                    <a target=\"\" rel=\"\" href=\"https:\/\/www.millboard.com\/en-us\/shop\/composite-decking\/duospan-51-straight-connector-kit-box-of-10-sets\/\" class=\"navigation-tiles__tile-cta g-button\">View Product<\/a>\n                                            <\/div>\n                                    <div class=\"navigation-tiles__tile\">\n                                                    <h3 class=\"navigation-tiles__tile-title\">\n                                DuoSpan 99 \u2013 90 Degree Bracket Kit Box of 10 sets                            <\/h3>\n                                                \n                                                \n                                                    <a target=\"\" rel=\"\" href=\"https:\/\/www.millboard.com\/en-us\/shop\/composite-decking\/duospan-99-90-degree-bracket-kit-box-of-10-sets\/\" class=\"navigation-tiles__tile-cta g-button\">View Product<\/a>\n                                            <\/div>\n                                    <div class=\"navigation-tiles__tile\">\n                                                    <h3 class=\"navigation-tiles__tile-title\">\n                                DuoSpan 99 Flexible Bracket Kit Box of 10 sets                            <\/h3>\n                                                \n                                                \n                                                    <a target=\"\" rel=\"\" href=\"https:\/\/www.millboard.com\/en-us\/shop\/composite-decking\/duospan-99-flexible-bracket-kit-box-of-10-sets\/\" class=\"navigation-tiles__tile-cta g-button\">View Product<\/a>\n                                            <\/div>\n                                    <div class=\"navigation-tiles__tile\">\n                                                    <h3 class=\"navigation-tiles__tile-title\">\n                                DuoSpan 99 Joist Aluminium                            <\/h3>\n                                                \n                                                \n                                                    <a target=\"\" rel=\"\" href=\"https:\/\/www.millboard.com\/en-us\/shop\/composite-decking\/duospan-99-joist-aluminium\/\" class=\"navigation-tiles__tile-cta g-button\">View Product<\/a>\n                                            <\/div>\n                                    <div class=\"navigation-tiles__tile\">\n                                                    <h3 class=\"navigation-tiles__tile-title\">\n                                DuoSpan 99 Straight Connector Kit Box of 10 sets                            <\/h3>\n                                                \n                                                \n                                                    <a target=\"\" rel=\"\" href=\"https:\/\/www.millboard.com\/en-us\/shop\/composite-decking\/duospan-99-straight-connector-kit-box-of-10-sets-2\/\" class=\"navigation-tiles__tile-cta g-button\">View Product<\/a>\n                                            <\/div>\n                                    <div class=\"navigation-tiles__tile\">\n                                                    <h3 class=\"navigation-tiles__tile-title\">\n                                DuoSpan Beam Aluminium                            <\/h3>\n                                                \n                                                \n                                                    <a target=\"\" rel=\"\" href=\"https:\/\/www.millboard.com\/en-us\/shop\/composite-decking\/duospan-beam-aluminium\/\" class=\"navigation-tiles__tile-cta g-button\">View Product<\/a>\n                                            <\/div>\n                                    <div class=\"navigation-tiles__tile\">\n                                                    <h3 class=\"navigation-tiles__tile-title\">\n                                DuoSpan Hold Down Clip Set Box of 30 sets                            <\/h3>\n                                                \n                                                \n                                                    <a target=\"\" rel=\"\" href=\"https:\/\/www.millboard.com\/en-us\/shop\/composite-decking\/duospan-hold-down-clip-set-box-of-30-sets-2\/\" class=\"navigation-tiles__tile-cta g-button\">View Product<\/a>\n                                            <\/div>\n                            <\/div>\n            <\/div>\n<\/div>\n\n\n<div class=\"list-values wp-block alignfull has-background has-brand-5-background-color\">\n    <div class=\"list-values__inner\">\n                    <div class=\"list-values__header\">\n                                \n                                    <h2 id=\"the-benefits-of-duospan-decking-subframes\" class=\"list-values__heading\">\n                        The Benefits of DuoSpan Decking Subframes                    <\/h2>\n                            <\/div>\n        \n                    <div class=\"list-values__values\">\n                                    <div class=\"list-values__value\">\n                                                    <div class=\"list-values__value-icon\">\n                                <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewBox=\"0 0 29 29\" fill=\"none\" role=\"img\" aria-hidden=\"true\" width=\"29\" height=\"29\">\n  <path d=\"M27.7573 5.4875L23.1216 0.851786C21.9859 -0.283929 20.2359 -0.283929 19.1002 0.851786L3.53588 16.4161C3.0216 16.9304 2.71445 17.5518 2.50731 18.1661L0.0358821 26.7161C-0.0641179 27.2304 0.0358821 27.8518 0.450168 28.1589C0.757311 28.4661 1.1716 28.5732 1.58588 28.5732H2.00017L10.5502 26.1018C11.2716 25.8946 11.893 25.5875 12.3002 25.0732L27.8645 9.50893C28.893 8.48036 28.893 6.62322 27.7645 5.4875H27.7573ZM2.9216 23.3161L5.29302 25.6875L1.89302 26.7161L2.9216 23.3161ZM26.4145 8.27321L10.8502 23.8375C10.543 24.1446 10.2287 24.3518 9.8216 24.4589L7.24303 25.1804L3.42874 21.3661L4.15017 18.7875C4.25017 18.3732 4.45731 18.0661 4.7716 17.7589L20.3359 2.19464C20.543 1.9875 20.7502 1.8875 21.0573 1.8875C21.3645 1.8875 21.5716 1.9875 21.7787 2.19464L26.4145 6.83036C26.8287 7.24464 26.8287 7.85893 26.4145 8.27321Z\" fill=\"currentColor\"\/>\n<\/svg>                            <\/div>\n                                                \n                        <div class=\"list-values__value-content\">\n                                                            <h3 class=\"list-values__value-heading\">\n                                    Flexible connectivity                                <\/h3>\n                                                        \n                                                            <div class=\"list-values__value-description\">\n                                    Multiple brackets for all types of joints, including Flexible Brackets for non-standard angles and curves.                                <\/div>\n                                                    <\/div>\n                    <\/div>\n                                    <div class=\"list-values__value\">\n                                                    <div class=\"list-values__value-icon\">\n                                <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewBox=\"0 0 29 29\" fill=\"none\" role=\"img\" aria-hidden=\"true\" width=\"29\" height=\"29\">\n  <path d=\"M27.7573 5.4875L23.1216 0.851786C21.9859 -0.283929 20.2359 -0.283929 19.1002 0.851786L3.53588 16.4161C3.0216 16.9304 2.71445 17.5518 2.50731 18.1661L0.0358821 26.7161C-0.0641179 27.2304 0.0358821 27.8518 0.450168 28.1589C0.757311 28.4661 1.1716 28.5732 1.58588 28.5732H2.00017L10.5502 26.1018C11.2716 25.8946 11.893 25.5875 12.3002 25.0732L27.8645 9.50893C28.893 8.48036 28.893 6.62322 27.7645 5.4875H27.7573ZM2.9216 23.3161L5.29302 25.6875L1.89302 26.7161L2.9216 23.3161ZM26.4145 8.27321L10.8502 23.8375C10.543 24.1446 10.2287 24.3518 9.8216 24.4589L7.24303 25.1804L3.42874 21.3661L4.15017 18.7875C4.25017 18.3732 4.45731 18.0661 4.7716 17.7589L20.3359 2.19464C20.543 1.9875 20.7502 1.8875 21.0573 1.8875C21.3645 1.8875 21.5716 1.9875 21.7787 2.19464L26.4145 6.83036C26.8287 7.24464 26.8287 7.85893 26.4145 8.27321Z\" fill=\"currentColor\"\/>\n<\/svg>                            <\/div>\n                                                \n                        <div class=\"list-values__value-content\">\n                                                            <h3 class=\"list-values__value-heading\">\n                                    Slot-and-screw assembly                                <\/h3>\n                                                        \n                                                            <div class=\"list-values__value-description\">\n                                    Screw-locating grooves and self-drilling screws ensure accurate alignment and a fast fix that\u2019s right every time.                                <\/div>\n                                                    <\/div>\n                    <\/div>\n                                    <div class=\"list-values__value\">\n                                                    <div class=\"list-values__value-icon\">\n                                <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewBox=\"0 0 29 29\" fill=\"none\" role=\"img\" aria-hidden=\"true\" width=\"29\" height=\"29\">\n  <path d=\"M27.7573 5.4875L23.1216 0.851786C21.9859 -0.283929 20.2359 -0.283929 19.1002 0.851786L3.53588 16.4161C3.0216 16.9304 2.71445 17.5518 2.50731 18.1661L0.0358821 26.7161C-0.0641179 27.2304 0.0358821 27.8518 0.450168 28.1589C0.757311 28.4661 1.1716 28.5732 1.58588 28.5732H2.00017L10.5502 26.1018C11.2716 25.8946 11.893 25.5875 12.3002 25.0732L27.8645 9.50893C28.893 8.48036 28.893 6.62322 27.7645 5.4875H27.7573ZM2.9216 23.3161L5.29302 25.6875L1.89302 26.7161L2.9216 23.3161ZM26.4145 8.27321L10.8502 23.8375C10.543 24.1446 10.2287 24.3518 9.8216 24.4589L7.24303 25.1804L3.42874 21.3661L4.15017 18.7875C4.25017 18.3732 4.45731 18.0661 4.7716 17.7589L20.3359 2.19464C20.543 1.9875 20.7502 1.8875 21.0573 1.8875C21.3645 1.8875 21.5716 1.9875 21.7787 2.19464L26.4145 6.83036C26.8287 7.24464 26.8287 7.85893 26.4145 8.27321Z\" fill=\"currentColor\"\/>\n<\/svg>                            <\/div>\n                                                \n                        <div class=\"list-values__value-content\">\n                                                            <h3 class=\"list-values__value-heading\">\n                                    Unique curved constructions                                <\/h3>\n                                                        \n                                                            <div class=\"list-values__value-description\">\n                                    The combination of rigid DuoSpan\u00ae aluminium joists with flexible Plas-Pro enables the construction of stunning, yet durable curved designs.                                <\/div>\n                                                    <\/div>\n                    <\/div>\n                                    <div class=\"list-values__value\">\n                                                    <div class=\"list-values__value-icon\">\n                                <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewBox=\"0 0 29 29\" fill=\"none\" role=\"img\" aria-hidden=\"true\" width=\"29\" height=\"29\">\n  <path d=\"M27.7573 5.4875L23.1216 0.851786C21.9859 -0.283929 20.2359 -0.283929 19.1002 0.851786L3.53588 16.4161C3.0216 16.9304 2.71445 17.5518 2.50731 18.1661L0.0358821 26.7161C-0.0641179 27.2304 0.0358821 27.8518 0.450168 28.1589C0.757311 28.4661 1.1716 28.5732 1.58588 28.5732H2.00017L10.5502 26.1018C11.2716 25.8946 11.893 25.5875 12.3002 25.0732L27.8645 9.50893C28.893 8.48036 28.893 6.62322 27.7645 5.4875H27.7573ZM2.9216 23.3161L5.29302 25.6875L1.89302 26.7161L2.9216 23.3161ZM26.4145 8.27321L10.8502 23.8375C10.543 24.1446 10.2287 24.3518 9.8216 24.4589L7.24303 25.1804L3.42874 21.3661L4.15017 18.7875C4.25017 18.3732 4.45731 18.0661 4.7716 17.7589L20.3359 2.19464C20.543 1.9875 20.7502 1.8875 21.0573 1.8875C21.3645 1.8875 21.5716 1.9875 21.7787 2.19464L26.4145 6.83036C26.8287 7.24464 26.8287 7.85893 26.4145 8.27321Z\" fill=\"currentColor\"\/>\n<\/svg>                            <\/div>\n                                                \n                        <div class=\"list-values__value-content\">\n                                                            <h3 class=\"list-values__value-heading\">\n                                    Exceptional spans                                <\/h3>\n                                                        \n                                                            <div class=\"list-values__value-description\">\n                                    The DuoSpan\u00ae 99mm Joist provides an exceptional 1800mm span in residential applications, reducing the number of posts or joist supports required.                                <\/div>\n                                                    <\/div>\n                    <\/div>\n                                    <div class=\"list-values__value\">\n                                                    <div class=\"list-values__value-icon\">\n                                <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewBox=\"0 0 29 29\" fill=\"none\" role=\"img\" aria-hidden=\"true\" width=\"29\" height=\"29\">\n  <path d=\"M27.7573 5.4875L23.1216 0.851786C21.9859 -0.283929 20.2359 -0.283929 19.1002 0.851786L3.53588 16.4161C3.0216 16.9304 2.71445 17.5518 2.50731 18.1661L0.0358821 26.7161C-0.0641179 27.2304 0.0358821 27.8518 0.450168 28.1589C0.757311 28.4661 1.1716 28.5732 1.58588 28.5732H2.00017L10.5502 26.1018C11.2716 25.8946 11.893 25.5875 12.3002 25.0732L27.8645 9.50893C28.893 8.48036 28.893 6.62322 27.7645 5.4875H27.7573ZM2.9216 23.3161L5.29302 25.6875L1.89302 26.7161L2.9216 23.3161ZM26.4145 8.27321L10.8502 23.8375C10.543 24.1446 10.2287 24.3518 9.8216 24.4589L7.24303 25.1804L3.42874 21.3661L4.15017 18.7875C4.25017 18.3732 4.45731 18.0661 4.7716 17.7589L20.3359 2.19464C20.543 1.9875 20.7502 1.8875 21.0573 1.8875C21.3645 1.8875 21.5716 1.9875 21.7787 2.19464L26.4145 6.83036C26.8287 7.24464 26.8287 7.85893 26.4145 8.27321Z\" fill=\"currentColor\"\/>\n<\/svg>                            <\/div>\n                                                \n                        <div class=\"list-values__value-content\">\n                                                            <h3 class=\"list-values__value-heading\">\n                                    Rot and corrosion-resistant                                <\/h3>\n                                                        \n                                                            <div class=\"list-values__value-description\">\n                                    Galvanic corrosion between different metals is minimised with our cathodic barrier fixings. Aluminium is naturally resistant to moisture, rotting and hosting algae.                                <\/div>\n                                                    <\/div>\n                    <\/div>\n                                    <div class=\"list-values__value\">\n                                                    <div class=\"list-values__value-icon\">\n                                <svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" viewBox=\"0 0 29 29\" fill=\"none\" role=\"img\" aria-hidden=\"true\" width=\"29\" height=\"29\">\n  <path d=\"M27.7573 5.4875L23.1216 0.851786C21.9859 -0.283929 20.2359 -0.283929 19.1002 0.851786L3.53588 16.4161C3.0216 16.9304 2.71445 17.5518 2.50731 18.1661L0.0358821 26.7161C-0.0641179 27.2304 0.0358821 27.8518 0.450168 28.1589C0.757311 28.4661 1.1716 28.5732 1.58588 28.5732H2.00017L10.5502 26.1018C11.2716 25.8946 11.893 25.5875 12.3002 25.0732L27.8645 9.50893C28.893 8.48036 28.893 6.62322 27.7645 5.4875H27.7573ZM2.9216 23.3161L5.29302 25.6875L1.89302 26.7161L2.9216 23.3161ZM26.4145 8.27321L10.8502 23.8375C10.543 24.1446 10.2287 24.3518 9.8216 24.4589L7.24303 25.1804L3.42874 21.3661L4.15017 18.7875C4.25017 18.3732 4.45731 18.0661 4.7716 17.7589L20.3359 2.19464C20.543 1.9875 20.7502 1.8875 21.0573 1.8875C21.3645 1.8875 21.5716 1.9875 21.7787 2.19464L26.4145 6.83036C26.8287 7.24464 26.8287 7.85893 26.4145 8.27321Z\" fill=\"currentColor\"\/>\n<\/svg>                            <\/div>\n                                                \n                        <div class=\"list-values__value-content\">\n                                                            <h3 class=\"list-values__value-heading\">\n                                    Simple, stable fixing                                <\/h3>\n                                                        \n                                                            <div class=\"list-values__value-description\">\n                                    Millboard decking can be easily and securely screwed directly into the DuoSpan\u00ae subframe at almost any angle using Durafix 45mm screws.                                <\/div>\n                                                    <\/div>\n                    <\/div>\n                            <\/div>\n            <\/div>\n<\/div>\n\n\n<section data-allow-multiple=\"false\" class=\"accordion wp-block alignfull\">\n    <div class=\"accordion__inner\">\n\n        <div class=\"accordion__header\">\n\n            \n                            <h3 class=\"accordion__header__heading\">Frequently Asked Questions<\/h3>\n            \n            \n            \n        <\/div>\n\n        <div class=\"accordion__items\">\n<div class=\"accordion__item wp-block\">\n    <button aria-expanded=\"true\" aria-controls=\"accordion-panel-1\" type=\"button\" class=\"accordion__item__trigger js-accordion-button\" id=\"what-is-the-difference-between-duospan-and-plas-pro\"><h3 class=\"accordion__item__heading\">What is the difference between DuoSpan and Plas-Pro?<\/h3><\/button>\n\n    <div id=\"accordion-panel-1\" class=\"accordion__item__panel js-expandable-element\" aria-labelledby=\"what-is-the-difference-between-duospan-and-plas-pro\">\n        <div class=\"accordion__item__panel__inner\">\n            <p>DuoSpan uses aluminium joists for a heavy duty support system and recycled plastic for creating strong yet flexible edges. Meanwhile, the Plas-Pro system uses 100% recycled plastic joists and posts for a sturdy, non-rotting structure. The two systems are designed to work together, depending on the situation.<\/p>\n\n                    <\/div>\n    <\/div>\n<\/div>\n\n\n<div class=\"accordion__item wp-block\">\n    <button aria-expanded=\"false\" aria-controls=\"accordion-panel-2\" type=\"button\" class=\"accordion__item__trigger js-accordion-button\" id=\"what-is-the-load-capacity-of-duospan-joists\"><h3 class=\"accordion__item__heading\">What is the load capacity of DuoSpan joists?<\/h3><\/button>\n\n    <div id=\"accordion-panel-2\" class=\"accordion__item__panel js-expandable-element\" aria-labelledby=\"what-is-the-load-capacity-of-duospan-joists\" hidden=\"true\" aria-hidden=\"true\">\n        <div class=\"accordion__item__panel__inner\">\n            <p>The Allowable Load (for residential applications), recommended centres: 400mm joist centres, Joists and Beams supported every 1800mm centres (based on a UDL of up to 2.5kN\/m\u00b2 and a point load of 2.0kN as per Eurocode 1 Action on Structures BS EN 1991-1-1:2002.<\/p>\n<p>Allowable Load (for commercial applications), recommended centres: 300mm joist centres, Joists and Beams supported every 1200mm centres (based on a UDL of up to 5kN\/m\u00b2 and a point load of 3.6kN as per Eurocode 1 Action on Structures BS EN 1991-1-1:2002 &#8211;<\/p>\n<p>Please see DuoSpan loading tables for more information.<\/p>\n\n                    <\/div>\n    <\/div>\n<\/div>\n\n\n<div class=\"accordion__item wp-block\">\n    <button aria-expanded=\"false\" aria-controls=\"accordion-panel-3\" type=\"button\" class=\"accordion__item__trigger js-accordion-button\" id=\"what-is-the-maximum-joist-spacing-for-duospan\"><h3 class=\"accordion__item__heading\">What is the maximum joist spacing for DuoSpan?<\/h3><\/button>\n\n    <div id=\"accordion-panel-3\" class=\"accordion__item__panel js-expandable-element\" aria-labelledby=\"what-is-the-maximum-joist-spacing-for-duospan\" hidden=\"true\" aria-hidden=\"true\">\n        <div class=\"accordion__item__panel__inner\">\n            <p>The maximum, unsupported joist and beam spans for residential projects is 1800mm. Meanwhile, the minimum span for commercial projects is 1350mm. Read more about DuoSpan technical specifications here.<\/p>\n\n                    <\/div>\n    <\/div>\n<\/div>\n\n<\/div>\n    <\/div>\n<\/section>\n\n\n<div class=\"navigation-tiles wp-block alignfull has-background has-brand-5-background-color\">\n    <div class=\"navigation-tiles__inner\">\n                    <div class=\"navigation-tiles__header\">\n                                    <div class=\"navigation-tiles__preheading is-style-typestyle-h6\">\n                        Plan your space                    <\/div>\n                                \n                                    <h2 id=\"simple-tools-and-expert-support\" class=\"navigation-tiles__heading\">\n                        Simple tools and expert support.                      <\/h2>\n                            <\/div>\n        \n                    <div class=\"navigation-tiles__tiles\">\n                                    <div class=\"navigation-tiles__tile\">\n                                                    <h3 class=\"navigation-tiles__tile-title\">\n                                Decking configurator                            <\/h3>\n                                                \n                                                    <div class=\"navigation-tiles__tile-description\">\n                                <p>Estimate the boards, fixings, subframe and more you need for your space.<\/p>\n                            <\/div>\n                                                \n                                                    <a target=\"\" rel=\"\" href=\"https:\/\/deckplanner.www.millboard.com\/\" class=\"navigation-tiles__tile-cta g-button\">Open Configurator<\/a>\n                                            <\/div>\n                                    <div class=\"navigation-tiles__tile\">\n                                                    <h3 class=\"navigation-tiles__tile-title\">\n                                Request A Quote                            <\/h3>\n                                                \n                                                    <div class=\"navigation-tiles__tile-description\">\n                                <p>Get accurate pricing and product recommendations for your project.<\/p>\n                            <\/div>\n                                                \n                                                    <a target=\"\" rel=\"\" href=\"https:\/\/www.millboard.com\/en-us\/contact-us\/\" class=\"navigation-tiles__tile-cta g-button\">Contact Us<\/a>\n                                            <\/div>\n                                    <div class=\"navigation-tiles__tile\">\n                                                    <h3 class=\"navigation-tiles__tile-title\">\n                                Installation guides                            <\/h3>\n                                                \n                                                    <div class=\"navigation-tiles__tile-description\">\n                                <p>Step by step fixing advice and detailing for every collection.<\/p>\n                            <\/div>\n                                                \n                                                    <a target=\"\" rel=\"\" href=\"https:\/\/www.millboard.com\/en-us\/product-brochures\/\" class=\"navigation-tiles__tile-cta g-button\">Browse guides<\/a>\n                                            <\/div>\n                                    <div class=\"navigation-tiles__tile\">\n                                                    <h3 class=\"navigation-tiles__tile-title\">\n                                Free product samples                            <\/h3>\n                                                \n                                                    <div class=\"navigation-tiles__tile-description\">\n                                <p>Order some samples to see how Millboard works for your project.<\/p>\n                            <\/div>\n                                                \n                                                    <a target=\"\" rel=\"\" href=\"https:\/\/www.www.millboard.com\/en-us\/product-category\/siding-samples\/\" class=\"navigation-tiles__tile-cta g-button\">Order Samples Today<\/a>\n                                            <\/div>\n                            <\/div>\n            <\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":10,"featured_media":0,"parent":6442,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"_acf_changed":false,"content-type":"","footnotes":""},"class_list":["post-6452","page","type-page","status-publish","hentry"],"acf":[],"yoast_head":"<!-- This site is optimized with the Yoast SEO Premium plugin v27.3 (Yoast SEO v27.3) - https:\/\/yoast.com\/product\/yoast-seo-premium-wordpress\/ -->\n<title>DuoSpan Decking Subframe System | Millboard<\/title>\n<meta name=\"description\" content=\"DuoSpan is Millboard&#039;s durable aluminium decking subframe system, engineered for strong, long-lasting composite decking installations across the USA.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.millboard.com\/en-us\/composite-decking-collections\/decking-subframes\/duospan\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"DuoSpan\" \/>\n<meta property=\"og:description\" content=\"DuoSpan is Millboard&#039;s durable aluminium decking subframe system, engineered for strong, long-lasting composite decking installations across the USA.\" \/>\n<meta property=\"og:url\" content=\"https:\/\/www.millboard.com\/en-us\/composite-decking-collections\/decking-subframes\/duospan\/\" \/>\n<meta property=\"og:site_name\" content=\"EN-US - Residential\" \/>\n<meta property=\"article:modified_time\" content=\"2026-03-09T19:23:43+00:00\" \/>\n<meta property=\"og:image\" content=\"https:\/\/www.millboard.com\/en-us\/wp-content\/uploads\/sites\/5\/2026\/02\/SL-Ebony-Grey-Shoot.jpg\" \/>\n\t<meta property=\"og:image:width\" content=\"2000\" \/>\n\t<meta property=\"og:image:height\" content=\"1263\" \/>\n\t<meta property=\"og:image:type\" content=\"image\/jpeg\" \/>\n<meta name=\"twitter:card\" content=\"summary_large_image\" \/>\n<meta name=\"twitter:label1\" content=\"Est. reading time\" \/>\n\t<meta name=\"twitter:data1\" content=\"1 minute\" \/>\n<script type=\"application\/ld+json\" class=\"yoast-schema-graph\">{\"@context\":\"https:\\\/\\\/schema.org\",\"@graph\":[{\"@type\":[\"WebPage\",\"FAQPage\"],\"@id\":\"https:\\\/\\\/www.millboard.com\\\/en-us\\\/composite-decking-collections\\\/decking-subframes\\\/duospan\\\/\",\"url\":\"https:\\\/\\\/www.millboard.com\\\/en-us\\\/composite-decking-collections\\\/decking-subframes\\\/duospan\\\/\",\"name\":\"DuoSpan Decking Subframe System | Millboard\",\"isPartOf\":{\"@id\":\"https:\\\/\\\/www.millboard.com\\\/en-us\\\/#website\"},\"datePublished\":\"2026-02-03T18:25:24+00:00\",\"dateModified\":\"2026-03-09T19:23:43+00:00\",\"description\":\"DuoSpan is Millboard's durable aluminium decking subframe system, engineered for strong, long-lasting composite decking installations across the USA.\",\"breadcrumb\":{\"@id\":\"https:\\\/\\\/www.millboard.com\\\/en-us\\\/composite-decking-collections\\\/decking-subframes\\\/duospan\\\/#breadcrumb\"},\"inLanguage\":\"en-US\",\"potentialAction\":[{\"@type\":\"ReadAction\",\"target\":[\"https:\\\/\\\/www.millboard.com\\\/en-us\\\/composite-decking-collections\\\/decking-subframes\\\/duospan\\\/\"]}]},{\"@type\":\"BreadcrumbList\",\"@id\":\"https:\\\/\\\/www.millboard.com\\\/en-us\\\/composite-decking-collections\\\/decking-subframes\\\/duospan\\\/#breadcrumb\",\"itemListElement\":[{\"@type\":\"ListItem\",\"position\":1,\"name\":\"Home\",\"item\":\"https:\\\/\\\/www.millboard.com\\\/en-us\\\/\"},{\"@type\":\"ListItem\",\"position\":2,\"name\":\"Composite Decking Collections\",\"item\":\"https:\\\/\\\/www.millboard.com\\\/en-us\\\/composite-decking-collections\\\/\"},{\"@type\":\"ListItem\",\"position\":3,\"name\":\"Decking Subframes\",\"item\":\"https:\\\/\\\/www.millboard.com\\\/en-us\\\/composite-decking-collections\\\/decking-subframes\\\/\"},{\"@type\":\"ListItem\",\"position\":4,\"name\":\"DuoSpan\"}]},{\"@type\":\"WebSite\",\"@id\":\"https:\\\/\\\/www.millboard.com\\\/en-us\\\/#website\",\"url\":\"https:\\\/\\\/www.millboard.com\\\/en-us\\\/\",\"name\":\"Millboard\",\"description\":\"Live. 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