{
  "slug": "wind-pressure-on-wall",
  "title": "Wind Pressure on a Wall Calculator",
  "heading": "Wind Pressure on a Wall Calculator",
  "category": "other",
  "url": "https://www.revenuelab.fyi/toolbox/wind-pressure-on-wall",
  "summary": "Estimate wind load force in psf and total pounds on a wall from wind speed.",
  "description": "Wind pressure on a flat surface grows with the square of wind speed, which is why hurricane-force winds are exponentially more destructive than a strong breeze rather than just proportionally worse. This calculator uses the standard dynamic wind pressure formula from ASCE 7 wind engineering, applying an air density constant and a pressure coefficient to convert wind speed into pounds per square foot, then multiplies by wall area to get total lateral force. This is the same basic physics behind window and siding wind-rating requirements in coastal building codes, and it's why hurricane-rated windows are tested to withstand specific psf pressures rather than just a wind speed number.",
  "formula": "q = 0.00256 × V² (psf, V in mph); wall pressure = q × Cp (pressure coefficient); total force = pressure × wall area.",
  "dateModified": "2026-09-30",
  "run_url": "https://www.revenuelab.fyi/api/public/calc?tool=wind-pressure-on-wall",
  "inputs": [
    {
      "id": "windSpeed",
      "label": "Sustained wind speed",
      "kind": "number",
      "hint": null,
      "default": 100,
      "unit": "mph",
      "min": 10,
      "max": 200
    },
    {
      "id": "cp",
      "label": "Pressure coefficient (Cp)",
      "kind": "number",
      "hint": null,
      "default": 0.8,
      "unit": null,
      "min": 0.1,
      "max": 2
    },
    {
      "id": "wallArea",
      "label": "Wall area",
      "kind": "number",
      "hint": null,
      "default": 300,
      "unit": "sq ft",
      "min": 10,
      "max": null
    }
  ],
  "outputs": [
    {
      "id": "pressure",
      "label": "Wall pressure",
      "format": "number",
      "hint": null,
      "primary": true
    },
    {
      "id": "totalForce",
      "label": "Total lateral force",
      "format": "number",
      "hint": null,
      "primary": false
    },
    {
      "id": "tons",
      "label": "Total force (tons)",
      "format": "decimal",
      "hint": null,
      "primary": false
    },
    {
      "id": "q",
      "label": "Basic velocity pressure (q)",
      "format": "number",
      "hint": null,
      "primary": false
    }
  ],
  "worked_example": {
    "inputs": [
      "Sustained wind speed: 100 mph",
      "Pressure coefficient (Cp): 0.8",
      "Wall area: 300 sq ft"
    ],
    "outputs": [
      "Wall pressure: 20.5",
      "Total lateral force: 6,144",
      "Total force (tons): 3.07",
      "Basic velocity pressure (q): 25.6"
    ]
  },
  "how_to": {
    "title": "How to use this",
    "steps": [
      "Enter sustained wind speed (mph).",
      "Enter pressure coefficient (cp).",
      "Enter wall area (sq ft).",
      "Read your wall pressure on the right — it updates as you type.",
      "Hit Share to keep the scenario or send it to someone."
    ]
  },
  "scenarios": [
    {
      "name": "Conservative",
      "description": "Lower-end numbers — what if things land soft?",
      "values": {
        "windSpeed": 60,
        "cp": 0.48,
        "wallArea": 180
      }
    },
    {
      "name": "Typical",
      "description": "Defaults — the most common real-world setup.",
      "values": {
        "windSpeed": 100,
        "cp": 0.8,
        "wallArea": 300
      }
    },
    {
      "name": "Ambitious",
      "description": "Higher-end numbers — what if things really pop?",
      "values": {
        "windSpeed": 160,
        "cp": 1.2800000000000002,
        "wallArea": 480
      }
    }
  ],
  "limitations": [
    "Estimates assume standard, average conditions — local rules, pricing, and materials vary.",
    "Results are rounded for readability; add a buffer before ordering, booking, or committing.",
    "Double-check anything with a real cost attached against a local quote."
  ],
  "faq": [
    {
      "q": "Why does pressure scale with the square of wind speed?",
      "a": "Dynamic pressure comes from kinetic energy of moving air, which scales with velocity squared, so doubling wind speed from 50 to 100 mph doesn't double the force — it quadruples it. That's the core reason hurricane category jumps feel so much more dangerous than the wind speed numbers alone suggest."
    },
    {
      "q": "What is the pressure coefficient (Cp) and how do I pick one?",
      "a": "Cp accounts for how wind pressure varies across different faces and corners of a building — windward walls typically run 0.7-0.9, leeward walls (suction) run negative around -0.3 to -0.5, and corner zones see amplified suction. Use ASCE 7 tables or a structural engineer for code-compliant design values."
    },
    {
      "q": "How does this relate to hurricane window/door wind ratings?",
      "a": "Impact-rated windows are tested and rated by the psf pressure they withstand plus large-missile impact resistance, derived from exactly this kind of calculation applied to the design wind speed for a given coastal zone and building height."
    },
    {
      "q": "Does building height change the pressure?",
      "a": "Yes significantly — wind speed increases with height above ground due to reduced surface friction, so taller walls and upper stories experience higher effective wind pressure than this simplified single-value estimate assumes; full code calculations apply a height and exposure category adjustment factor."
    }
  ],
  "related": [
    "https://www.revenuelab.fyi/toolbox/snow-load-roof",
    "https://www.revenuelab.fyi/toolbox/hurricane-deductible-calculator"
  ],
  "license": "CC-BY-4.0",
  "citation": "RevenueLab — Wind Pressure on a Wall Calculator (https://www.revenuelab.fyi/toolbox/wind-pressure-on-wall)"
}