{"id":66728,"date":"2026-10-13T08:45:49","date_gmt":"2026-10-13T05:45:49","guid":{"rendered":"https:\/\/wpcalc.com\/en\/?p=66728"},"modified":"2026-10-13T08:45:49","modified_gmt":"2026-10-13T05:45:49","slug":"wind-load","status":"publish","type":"post","link":"https:\/\/wpcalc.com\/en\/engineering\/wind-load\/","title":{"rendered":"Wind Load"},"content":{"rendered":"<section class=\"not-prose calculator-box\" aria-labelledby=\"calculator-title\"><div class=\"flex items-baseline sm:items-center justify-between gap-2 sm:gap-3\"><div class=\"flex flex-col sm:flex-row sm:items-center gap-2\"><span class=\"icon icon-calculator text-primary-700! text-base! dark:text-primary-300!\" aria-hidden=\"true\"><\/span><h2 id=\"calculator-title\" class=\"text-lg font-display font-bold\">Estimate Wind Pressure and Force on an Exposed Surface<\/h2><\/div><div class=\"calcdash-favorite group\">\n  <button type=\"button\" class=\"favorite\" id=\"favorite\" data-favorite-id=\"66728\" data-favorite-title=\"Wind Load\" data-favorite-url=\"https:\/\/wpcalc.com\/en\/engineering\/wind-load\/\" data-favorite-excerpt=\"Estimate the dynamic wind pressure and total wind force on any exposed surface, such as a wall, sign, panel or structure. Enter the wind speed, air density, exposed area and shape coefficient to get pressure in Pa and force in N and lbf.\" aria-label=\"Add to Favorites\" data-favorite-icon=\"icon icon-civil\">\n    <span class=\"icon icon-shape-star-empty\" aria-hidden=\"true\"><\/span>\n  <\/button>\n  <div class=\"calcdash-favorite__tip\" aria-hidden=\"true\">\n   <span class=\"favorite-tooltip\" id=\"favorite-tooltip\"><\/span>\n  <\/div>\n  <span class=\"sr-only\" role=\"status\" id=\"favorite-status\"><\/span>\n<\/div><\/div><form action=\"https:\/\/wpcalc.com\/en\/engineering\/wind-load\/\" method=\"POST\" class=\"calculator\" id=\"calculator-66728\" data-post=\"66728\"><fieldset class=\"fieldset-input is-2\"><legend class=\"sr-only\">Input Fields<\/legend><div class=\"field has-term\" id=\"input-1\"><label for=\"field-1\">Wind speed (v)<\/label><div class=\"term\">v<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><div class=\"field-group\"><input type=\"text\" name=\"wind_speed_v\" id=\"field-1\" aria-describedby=\"calc-info-1\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"120\" min=\"0.1\" value=\"120\"\/><div class=\"grid grid-cols-1\"><select id=\"field-2\" name=\"unit\" aria-label=\"Unit\"><option value=\"ms\">m\/s<\/option><option value=\"kmh\" selected>km\/h<\/option><option value=\"mph\">mph<\/option><option value=\"fts\">ft\/s<\/option><option value=\"kn\">knots<\/option><\/select><svg class=\"pointer-events-none col-start-1 row-start-1 mr-2 size-5 self-center justify-self-end text-gray-500 sm:size-4\" viewBox=\"0 0 16 16\" fill=\"currentColor\" aria-hidden=\"true\" data-slot=\"icon\">\n              <path fill-rule=\"evenodd\" d=\"M4.22 6.22a.75.75 0 0 1 1.06 0L8 8.94l2.72-2.72a.75.75 0 1 1 1.06 1.06l-3.25 3.25a.75.75 0 0 1-1.06 0L4.22 7.28a.75.75 0 0 1 0-1.06Z\" clip-rule=\"evenodd\" \/>\n            <\/svg><\/div><\/div><small id=\"calc-info-1\">Design or measured wind speed at the height of the surface<\/small><\/div><div class=\"field has-term\" id=\"input-2\"><label for=\"field-3\">Air density (\u03c1)<\/label><div class=\"term\">\u03c1<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><input type=\"text\" name=\"air_density_\" id=\"field-3\" aria-describedby=\"calc-unit-3 calc-info-3\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"1.225\" min=\"0.01\" value=\"1.225\"\/><div class=\"unit\" id=\"calc-unit-3\">kg\/m\u00b3<\/div><small id=\"calc-info-3\">1.225 kg\/m\u00b3 is standard air at 15 \u00b0C at sea level<\/small><\/div><div class=\"field has-term\" id=\"input-3\"><label for=\"field-4\">Exposed area (A)<\/label><div class=\"term\">A<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><div class=\"field-group\"><input type=\"text\" name=\"exposed_area_a\" id=\"field-4\" aria-describedby=\"calc-info-4\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"10\" min=\"0.0001\" value=\"10\"\/><div class=\"grid grid-cols-1\"><select id=\"field-5\" name=\"unit\" aria-label=\"Unit\"><option value=\"m2\" selected>m\u00b2<\/option><option value=\"cm2\">cm\u00b2<\/option><option value=\"ft2\">ft\u00b2<\/option><option value=\"in2\">in\u00b2<\/option><\/select><svg class=\"pointer-events-none col-start-1 row-start-1 mr-2 size-5 self-center justify-self-end text-gray-500 sm:size-4\" viewBox=\"0 0 16 16\" fill=\"currentColor\" aria-hidden=\"true\" data-slot=\"icon\">\n              <path fill-rule=\"evenodd\" d=\"M4.22 6.22a.75.75 0 0 1 1.06 0L8 8.94l2.72-2.72a.75.75 0 1 1 1.06 1.06l-3.25 3.25a.75.75 0 0 1-1.06 0L4.22 7.28a.75.75 0 0 1 0-1.06Z\" clip-rule=\"evenodd\" \/>\n            <\/svg><\/div><\/div><small id=\"calc-info-4\">Projected frontal area the wind acts on<\/small><\/div><div class=\"field is-single has-term\" id=\"input-4\"><label for=\"field-6\">Pressure \/ drag coefficient (C)<\/label><div class=\"term\">C<\/div>  <div class=\"absolute bottom-0 left-16 top-8 w-2 h-0.5 bg-blue-500\"><\/div><input type=\"text\" name=\"pressure_drag_coefficient_c\" id=\"field-6\" aria-describedby=\"calc-info-6\" data-number inputmode=\"decimal\" autocomplete=\"off\" spellcheck=\"false\" placeholder=\"1.2\" min=\"0.01\" value=\"1.2\"\/><small id=\"calc-info-6\">Typical values: flat wall or sign 1.2\u20131.3, cylinder 0.8\u20131.2, sphere 0.47, streamlined shape 0.1\u20130.3<\/small><\/div><\/fieldset><div class=\"buttons\"><button type=\"submit\" data-text=\"Re-Calculate\" id=\"calculate-button\" data-post=\"66728\">Calculate<\/button><button type=\"reset\">Reset<\/button><\/div><div class=\"field is-checkbox hidden!\" id=\"field-auto-calc\"><input type=\"checkbox\" id=\"auto-calc\"><label for=\"auto-calc\">Calculate automatically<\/label><small>If enabled, the result will update automatically when you change any value.<\/small><\/div><div class=\"fieldset-result is-hidden\" aria-labelledby=\"result-title\" aria-live=\"polite\" role=\"region\"> <h3 class=\"result-title bg-gradient-to-r from-primary-50 to-gray-50 dark:from-primary-900 dark:to-gray-800\" id=\"result-title\"><span class=\"icon icon-s-pulse\" aria-hidden=\"true\"><\/span> Wind Load Results<\/h3><div class=\"result-box\"><div class=\"field-result\" id=\"output-1\"><span class=\"field-title\"><span>Dynamic pressure<\/span><span class=\"result-term\">q<\/span><\/span><span class=\"field-value\" id=\"result-1\"><\/span><button type=\"button\" class=\"copy-result\" data-tooltip=\"Copy Result\" aria-label=\"Copy Result\"><span class=\"copy-icon icon icon-document-copy\" aria-hidden=\"true\"><\/span><\/button><\/div><div class=\"field-result\" id=\"output-2\"><span class=\"field-title\"><span>Estimated wind force<\/span><span class=\"result-term\">F<\/span><\/span><span class=\"field-value\" id=\"result-2\"><\/span><button type=\"button\" class=\"copy-result\" data-tooltip=\"Copy Result\" aria-label=\"Copy Result\"><span class=\"copy-icon icon icon-document-copy\" aria-hidden=\"true\"><\/span><\/button><\/div><div class=\"field-result is-column\" id=\"output-3\"><span class=\"field-title\"><span>Formula and notes<\/span><\/span><span class=\"field-value\" id=\"result-3\"><\/span><button type=\"button\" class=\"copy-result\" data-tooltip=\"Copy Result\" aria-label=\"Copy Result\"><span class=\"copy-icon icon icon-document-copy\" aria-hidden=\"true\"><\/span><\/button><\/div><\/div><div class=\"result-actions\"><button type=\"button\" class=\"copy-link\"><svg viewBox=\"0 0 20 20\" fill=\"currentColor\" aria-hidden=\"true\"><path d=\"M12.232 4.232a2.5 2.5 0 0 1 3.536 3.536l-1.225 1.224a.75.75 0 0 0 1.061 1.06l1.224-1.224a4 4 0 0 0-5.656-5.656l-3 3a4 4 0 0 0 .225 5.865.75.75 0 0 0 .977-1.138 2.5 2.5 0 0 1-.142-3.667l3-3Z\"\/><path d=\"M11.603 7.963a.75.75 0 0 0-.977 1.138 2.5 2.5 0 0 1 .142 3.667l-3 3a2.5 2.5 0 0 1-3.536-3.536l1.225-1.224a.75.75 0 0 0-1.061-1.06l-1.224 1.224a4 4 0 1 0 5.656 5.656l3-3a4 4 0 0 0-.225-5.865Z\"\/><\/svg><span class=\"copy-link__text\">Copy link to this calculation<\/span><\/button><span class=\"sr-only\" role=\"status\" id=\"copy-link-status\"><\/span><\/div><\/div><a href=\"#respond\" class=\"hidden transition-opacity duration-300 opacity-0 w-50 text-sm justify-center items-center gap-2 px-4 py-2 rounded bg-gray-200 text-gray-700 hover:bg-gray-300\" id=\"leave-comment\"><span class=\"icon icon-comments\" aria-hidden=\"true\"><\/span>Leave a Comment<\/a><\/form><\/section><section id=\"calc-reactions\" class=\"not-prose hidden my-12 bg-gradient-to-r from-primary-50 to-gray-50 border border-indigo-100 rounded-xl px-6 py-4 shadow-sm\" data-post=\"66728\" aria-live=\"polite\" aria-labelledby=\"calc-reactions-title\"><p id=\"calc-reactions-title\" class=\"text-sm text-gray-500 text-center mb-2\">How did this result make you feel?<\/p><div role=\"group\" aria-labelledby=\"calc-reactions-title\" class=\"grid grid-cols-3 sm:flex sm:flex-row sm:justify-around gap-4 sm:items-center sm:flex-wrap\"><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"like\"><span class=\"reaction-count\" data-reaction-count=\"like\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\ud83d\ude00 <\/span><span class=\"reaction-description font-medium\">Like <\/span><\/button><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"helpful\"><span class=\"reaction-count\" data-reaction-count=\"helpful\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\ud83d\udca1 <\/span><span class=\"reaction-description font-medium\">Helpful <\/span><\/button><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"confused\"><span class=\"reaction-count\" data-reaction-count=\"confused\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\ud83d\ude15 <\/span><span class=\"reaction-description font-medium\">Confused <\/span><\/button><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"disappointed\"><span class=\"reaction-count\" data-reaction-count=\"disappointed\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\ud83d\ude1e <\/span><span class=\"reaction-description font-medium\">Disappointed <\/span><\/button><button type=\"button\" aria-pressed=\"false\" class=\"reaction-btn flex flex-col items-center gap-1 text-sm text-gray-700 hover:text-primary-600 cursor-pointer transition-transform hover:scale-105\" data-reaction=\"inaccurate\"><span class=\"reaction-count\" data-reaction-count=\"inaccurate\">0<\/span><span class=\"reaction text-3xl\" aria-hidden=\"true\">\u274c <\/span><span class=\"reaction-description font-medium\">Inaccurate <\/span><\/button><\/div><div id=\"reaction-message\" class=\"hidden mt-8 rounded-md border border-primary-100 bg-white\/50 backdrop-blur-sm px-4 py-2 text-sm text-center shadow-sm\"><\/div><\/section><div class=\"calcdash-ad not-prose calcdash-ad--calc_result calcdash-ad--in-article\"><ins class=\"adsbygoogle\" style=\"display:block\" data-ad-client=\"ca-pub-1721569815777345\" data-ad-slot=\"6317458308\" data-ad-layout=\"in-article\" data-ad-format=\"fluid\"><\/ins><script>(adsbygoogle = window.adsbygoogle || []).push({});<\/script><\/div>\n<style id=\"wpcoderpro-inline-1\">.formula-box {\r\n\tborder-bottom: none !important;\r\n}<\/style><section class=\"formula-box\" aria-labelledby=\"formula-title\">\r\n\t<div id=\"formula-title\" class=\"not-prose font-display mb-4\"><span class=\"icon icon-formula\" aria-hidden=\"true\"><\/span><h2>Wind Load Formula<\/h2><\/div>\r\n\t<figure class=\"not-prose formula\">\r\n\t\t<figcaption class=\"formula-title\">Formula<\/figcaption>\r\n\t\t<div class=\"text-base text-gray-800\" id=\"formula\">\n\\[ q = \\tfrac{1}{2}\\,\\rho\\,v^{2} \\]\n\\[ F = q \\cdot A \\cdot C \\]\n<\/div>\r\n\t<\/figure>\r\n\t<\/p>\n<p><strong>Where:<\/strong><\/p>\n<ul>\n<li>\\(q\\) \u2014 dynamic wind pressure (Pa)<\/li>\n<li>\\(F\\) \u2014 wind force on the surface (N)<\/li>\n<li>\\(\\rho\\) \u2014 air density (kg\/m\u00b3; 1.225 kg\/m\u00b3 at sea level, 15 \u00b0C)<\/li>\n<li>\\(v\\) \u2014 wind speed at the height of the surface (m\/s)<\/li>\n<li>\\(A\\) \u2014 projected frontal area the wind acts on (m\u00b2)<\/li>\n<li>\\(C\\) \u2014 pressure or drag coefficient (dimensionless, depends on shape)<\/li>\n<\/ul>\n<p>The first equation gives the kinetic energy per unit volume of the moving air, which becomes stagnation pressure when the wind is stopped by a surface. The second converts that pressure into a total force, scaled by the exposed area and the shape coefficient.<\/p>\n<p>\r\n<\/section>\n<style id=\"wpcoderpro-inline-459\">.calculation-box {\r\n\tborder-bottom: none !important;\r\n}<\/style><section id=\"calculation\" class=\"calculation-box\" aria-labelledby=\"calculation-title\">\r\n\t<div id=\"calculation-title\" class=\"not-prose font-display\"><span class=\"icon icon-unordered-list\" aria-hidden=\"true\"><\/span><h2>Wind Load \u2013 Calculation Example<\/h2><\/div>\r\n\r\n<\/p>\n<p><strong>Example:<\/strong> a flat rectangular sign with a projected area of 10 m\u00b2 faces a wind of 120 km\/h. The air density is 1.225 kg\/m\u00b3 (standard sea-level air) and the pressure coefficient for a flat surface is 1.2.<\/p>\n<p>\\[ v = 120\\ \\text{km\/h} = \\frac{120}{3.6} = 33.33\\ \\text{m\/s} \\]<\/p>\n<p>\\[ q = \\tfrac{1}{2} \\cdot 1.225 \\cdot 33.33^{2} = 680.6\\ \\text{Pa} \\]<\/p>\n<p>\\[ F = 680.6 \\cdot 10 \\cdot 1.2 = 8167\\ \\text{N} \\]<\/p>\n<p><strong>Result:<\/strong> the dynamic pressure is about 680.6 Pa (\u2248 14.2 lbf\/ft\u00b2) and the wind force is about 8167 N (\u2248 1835.9 lbf), equivalent to roughly 833 kgf pressing on the sign.<\/p>\n<p>\n\r\n<\/section>\n<h2>How to use the calculator<\/h2>\n<ol>\n<li>Enter the <strong>Wind speed (v)<\/strong> at the height of the surface and select its unit \u2014 m\/s, km\/h, mph, ft\/s or knots. Make sure you use the design gust speed, not a calm-weather average, when checking a structure.<\/li>\n<li>Enter the <strong>Air density (\u03c1)<\/strong> in kg\/m\u00b3. The default 1.225 kg\/m\u00b3 is correct for sea-level air at 15 \u00b0C; reduce it by roughly 10 % for hot climates or high-altitude sites.<\/li>\n<li>Enter the <strong>Exposed area (A)<\/strong> \u2014 the projected frontal area facing the wind, not the total surface area \u2014 and choose m\u00b2, cm\u00b2, ft\u00b2 or in\u00b2.<\/li>\n<li>Enter the <strong>Pressure \/ drag coefficient (C)<\/strong>. Use 1.2\u20131.3 for a flat wall or sign, 0.8\u20131.2 for a cylinder, 0.47 for a sphere and 0.1\u20130.3 for a streamlined shape.<\/li>\n<li>Read the <strong>Dynamic pressure<\/strong> in Pa (with lbf\/ft\u00b2) and the <strong>Estimated wind force<\/strong> in N, lbf and kgf.<\/li>\n<\/ol>\n<h2>What is wind load and why it matters<\/h2>\n<p>Wind load is the force that moving air exerts on an object in its path. When wind hits a wall, fence, sign, solar panel or antenna, the air decelerates and its kinetic energy is converted into pressure on the surface. Because that pressure grows with the <em>square<\/em> of the wind speed, doubling the wind speed quadruples the load: a breeze of 30 km\/h that pushes with barely noticeable force becomes a serious structural demand at 120 km\/h.<\/p>\n<p>The dynamic pressure \\(q = \\tfrac{1}{2}\\rho v^{2}\\) is the same quantity used in aerodynamics and is the starting point of every wind-load standard. Multiplying it by the exposed area \\(A\\) gives the force on a perfectly flat, bluff plate; the coefficient \\(C\\) then corrects for the real shape. Streamlined bodies deflect the air gently and carry low coefficients, while flat plates and sharp-edged bodies stop the flow abruptly and experience the highest pressure.<\/p>\n<p>Interpreting the result is straightforward: the force is the total push on the surface, acting roughly at the centre of the exposed area. For the example sign, 8167 N is equivalent to hanging a mass of about 833 kg on the supports \u2014 which is why signposts, masts and fa\u00e7ade anchors are sized for wind rather than for the weight of the structure itself. If you then need to check whether a supporting member can carry this force, the <a href=\"https:\/\/wpcalc.com\/en\/engineering\/beam-section-modulus\/\">beam section modulus<\/a> and <a href=\"https:\/\/wpcalc.com\/en\/engineering\/simply-supported-beam-with-uniform-load\/\">uniformly loaded beam<\/a> calculators are useful next steps.<\/p>\n<h2>Choosing the wind speed and coefficient<\/h2>\n<p>Use the strongest wind the surface is expected to survive, typically a design gust speed from a local wind map or building code. Remember that wind speed increases with height above ground and that open sites experience stronger winds than sheltered urban terrain. If only an average speed is available, gusts can exceed it by 30\u201350 %.<\/p>\n<p>The coefficient \\(C\\) depends on geometry and flow direction. A few reliable reference values: 1.2\u20131.3 for flat plates, walls and signs normal to the flow; about 0.47 for a sphere; 0.8\u20131.2 for a circular cylinder (the value drops toward the lower end at high Reynolds numbers \u2014 see the <a href=\"https:\/\/wpcalc.com\/en\/engineering\/reynolds-number\/\">Reynolds number calculator<\/a>); 0.1\u20130.3 for streamlined shapes such as airfoils. For angled surfaces, the projected area and the coefficient both change; conservative practice is to assume the wind hits the surface squarely.<\/p>\n<h2>Assumptions and limitations<\/h2>\n<ul>\n<li>The calculation is a simplified static estimate: it assumes steady, uniform wind hitting the surface squarely, and it ignores gust turbulence, resonance and vibration effects.<\/li>\n<li>Formal design standards such as ASCE 7 or Eurocode EN 1991-1-4 add factors for terrain roughness, exposure category, height above ground, gust response and internal pressure on enclosed buildings. For permitted structures, always verify with the applicable code.<\/li>\n<li>Air density varies: at 2,000 m altitude or on a 35 \u00b0C day it can be 10\u201315 % lower than 1.225 kg\/m\u00b3, which reduces the load proportionally.<\/li>\n<li>For slender columns and masts, the wind force can trigger instability rather than simple bending \u2014 check the result against the <a href=\"https:\/\/wpcalc.com\/en\/engineering\/euler-buckling-load\/\">Euler buckling load<\/a> of the support.<\/li>\n<li>Flexible structures such as cables, chimneys and lighting poles may also be excited by vortex shedding at lower wind speeds than the static maximum, a fatigue effect this simple model does not cover.<\/li>\n<\/ul>\n<h2>Typical wind load reference values<\/h2>\n<p>The table below shows the dynamic pressure and the force on a 10 m\u00b2 flat wall (C = 1.2, \u03c1 = 1.225 kg\/m\u00b3) for several wind speeds, to help you sanity-check your own entries:<\/p>\n<table>\n<thead>\n<tr>\n<th>Wind speed<\/th>\n<th>Speed in m\/s<\/th>\n<th>Dynamic pressure q<\/th>\n<th>Force on 10 m\u00b2, C = 1.2<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td>50 km\/h<\/td>\n<td>13.9<\/td>\n<td>118 Pa<\/td>\n<td>1,419 N<\/td>\n<\/tr>\n<tr>\n<td>75 km\/h<\/td>\n<td>20.8<\/td>\n<td>266 Pa<\/td>\n<td>3,190 N<\/td>\n<\/tr>\n<tr>\n<td>100 km\/h<\/td>\n<td>27.8<\/td>\n<td>473 Pa<\/td>\n<td>5,678 N<\/td>\n<\/tr>\n<tr>\n<td>120 km\/h<\/td>\n<td>33.3<\/td>\n<td>681 Pa<\/td>\n<td>8,167 N<\/td>\n<\/tr>\n<tr>\n<td>150 km\/h<\/td>\n<td>41.7<\/td>\n<td>1,064 Pa<\/td>\n<td>12,773 N<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>The quadratic growth is clearly visible: going from 75 to 150 km\/h \u2014 a doubling of speed \u2014 increases the force fourfold. If your project involves moving air inside ductwork rather than wind on structures, the <a href=\"https:\/\/wpcalc.com\/en\/engineering\/fan-affinity-laws\/\">fan affinity laws<\/a> and <a href=\"https:\/\/wpcalc.com\/en\/engineering\/duct-pressure-drop\/\">duct pressure drop<\/a> calculators cover the related internal-flow questions.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Estimate the dynamic wind pressure and total wind force on any exposed surface, such as a wall, sign, panel or structure. Enter the wind speed, air density, exposed area and shape coefficient to get pressure in Pa and force in N and lbf.<\/p>\n","protected":false},"author":3168,"featured_media":0,"comment_status":"open","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[4],"tags":[19],"class_list":["post-66728","post","type-post","status-publish","format-standard","hentry","category-engineering","tag-civil"],"acf":[],"_links":{"self":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/66728","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/users\/3168"}],"replies":[{"embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/comments?post=66728"}],"version-history":[{"count":1,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/66728\/revisions"}],"predecessor-version":[{"id":66729,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/posts\/66728\/revisions\/66729"}],"wp:attachment":[{"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/media?parent=66728"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/categories?post=66728"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/wpcalc.com\/en\/wp-json\/wp\/v2\/tags?post=66728"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}