{"id":36223,"date":"2026-08-26T09:08:54","date_gmt":"2026-08-26T07:08:54","guid":{"rendered":"https:\/\/www.stevenshout.be\/wood-durability-class\/"},"modified":"2026-09-02T11:53:38","modified_gmt":"2026-09-02T09:53:38","slug":"wood-durability-class","status":"publish","type":"post","link":"https:\/\/www.stevenshout.be\/en\/wood-durability-class\/","title":{"rendered":"Wood Durability Class"},"content":{"rendered":"

[et_pb_section fb_built=”1″ _builder_version=”4.25.2″ _module_preset=”default” use_background_color_gradient=”on” background_color_gradient_stops=”#ffffff 70%|#f7f7f5 70%|#f7f7f5 100%” locked=”off” global_colors_info=”{}”][et_pb_row column_structure=”1_2,1_2″ _builder_version=”4.25.2″ _module_preset=”default” global_colors_info=”{}”][et_pb_column type=”1_2″ _builder_version=”4.25.2″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.8″ _module_preset=”default” text_font_size=”16px” text_line_height=”2em” header_font_size_tablet=”32px” header_font_size_phone=”26px” header_font_size_last_edited=”off|desktop” custom_css_free_form=”selector {|| hyphens: auto;|| overflow-wrap: break-word;||}” global_colors_info=”{}”]<\/p>\n

Durability Classes of Wood<\/h1>\n

[\/et_pb_text][\/et_pb_column][et_pb_column type=”1_2″ _builder_version=”4.25.2″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.27.7″ _module_preset=”default” text_font_size=”16px” text_line_height=”2em” global_colors_info=”{}”]The longevity of a project depends entirely on choosing the right type of wood<\/strong>. That\u2019s why, as a lumber supplier or professional, you should give your customers the right advice on the quality grade of wood for each project\u2014whether it\u2019s an exposed rooftop terrace or a sleek facade. <\/p>\n

The most important indicator for this is the wood\u2019s durability class<\/strong>. In this guide, we explain the systems used to determine these classes, what the various specifications entail, and which solution is best to offer your customers.[\/et_pb_text][et_pb_button button_url=”https:\/\/www.stevenshout.be\/en\/contact\/” button_text=”Ask us your question” _builder_version=”4.24.0″ _module_preset=”default” global_colors_info=”{}”][\/et_pb_button][\/et_pb_column][\/et_pb_row][et_pb_row _builder_version=”4.27.5″ _module_preset=”default” background_image=”https:\/\/www.stevenshout.be\/wp-content\/uploads\/iroko-terras.jpg” height=”60vh” max_height=”60vh” locked=”off” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.25.2″ _module_preset=”default” global_colors_info=”{}”][et_pb_image src=”https:\/\/www.stevenshout.be\/wp-content\/uploads\/Scroll-omlaag.png” alt=”Scroll down” title_text=”Scroll down” align=”right” _builder_version=”4.25.2″ _module_preset=”default” positioning=”absolute” position_origin_r=”top_right” vertical_offset=”-60px” horizontal_offset=”85px” z_index=”1″ vertical_offset_tablet=”-60px” vertical_offset_phone=”-45px” vertical_offset_last_edited=”on|phone” horizontal_offset_tablet=”85px” horizontal_offset_phone=”237px” horizontal_offset_last_edited=”on|phone” width=”100%” global_colors_info=”{}”][\/et_pb_image][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ _builder_version=”4.27.7″ _module_preset=”default” background_color=”#f7f7f5″ locked=”off” global_colors_info=”{}”][et_pb_row _builder_version=”4.24.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.24.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.24.0″ _module_preset=”default” header_2_font_size=”32px” global_colors_info=”{}”]<\/p>\n

2 testing systems that determine the wood quality grade<\/h2>\n

To measure the durability and resistance of wood, refer to the European standard NEN-EN 30. Within the wood industry, we primarily use two testing systems<\/strong> to determine how well the wood resists biological damage such as wood rot, mold, and insects.  <\/p>\n

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Ground Contact Test<\/h3>\n

This is the most commonly used test. In this test, untreated wooden stakes measuring 50 x 50 mm are placed in the ground. Then, measurements are taken  how long it takes for fungi to attack the wood<\/strong>. This measurement serves as the official basis for the five durability classes. Depending on the type of wood, this test can last anywhere from less than 5 years to more than 25 years. <\/p>\n

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Usage Classes<\/h3>\n

In addition to durability, we at Stevens Hout consider the usage classes. These classes (formerly known as risk classes) determine how humid the environment surrounding the wood may be<\/strong>. The system ranges from Class 1 for dry interior applications to Class 5 for wood that is constantly submerged in saltwater. This allows us to always select the perfect type of wood for every structure. <\/p>\n

[\/et_pb_text][\/et_pb_column][\/et_pb_row][\/et_pb_section][et_pb_section fb_built=”1″ admin_label=”hero-b5928e” _builder_version=”4.27.8″ _module_preset=”default” custom_css_free_form=”||selector ul li:before {|| font-family: %22Font Awesome 5 Free%22;|| font-weight: 900;|| content: %22%92f138%22;|| margin-right: 10px;|| color: #443630;||}||||selector ul{|| list-style: none;|| padding-left: 0;||}||||selector ul li {|| border-bottom: 1px solid rgba(0, 0, 0, 0.1);|| padding: 10px 0;||}” global_colors_info=”{}”][et_pb_row _builder_version=”4.24.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_column type=”4_4″ _builder_version=”4.24.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_text _builder_version=”4.24.0″ _module_preset=”default” global_colors_info=”{}”]<\/p>\n

Discover the 5 durability classes of wood<\/h2>\n

The most commonly used classification system divides wood into 5 durability classes, based on its expected lifespan when in direct contact with the ground<\/strong>. Class 1 indicates very durable, and Class 5 indicates non-durable. Thanks to this classification, you can always choose the most durable wood for outdoor use<\/a>. <\/p>\n

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[\/et_pb_text][\/et_pb_column][\/et_pb_row][et_pb_row column_structure=”1_3,1_3,1_3″ make_equal=”on” _builder_version=”4.27.7″ _module_preset=”default” custom_margin=”||||false|false” custom_padding=”0px||||false|false” custom_css_free_form=”selector .et_pb_blurb .et_pb_main_blurb_image,||.et_pb_blurb .et_pb_main_blurb_image .et_pb_image_wrap {|| display: block;|| width: 100%;|| max-width: 100%;||}||||selector .et_pb_blurb .et_pb_main_blurb_image img {|| display: block;|| width: 100%;|| height: auto;|| aspect-ratio: 3 \/ 2;|| object-fit: cover;|| object-position: center;||}” global_colors_info=”{}”][et_pb_column type=”1_3″ _builder_version=”4.24.0″ _module_preset=”default” global_colors_info=”{}”][et_pb_blurb title=”Class 1″ image=”https:\/\/www.stevenshout.be\/wp-content\/uploads\/Thermowood_Vuren_Uitzicht-scaled.jpg” alt=”Class 1 wood” content_max_width=”100%” _builder_version=”4.27.8″ _module_preset=”default” header_level=”h3″ global_colors_info=”{}”]<\/p>\n