Window heat loss calculator

Open Window heat loss calculator on Happytails.ai. This view has the same page content and links, with explicit tool capabilities. Read the processing notes before using a tool.

Tool capabilities

{
  "id": "window-heat-loss-calculator",
  "category": "calculators",
  "built": true,
  "requirements": "Up to 30 uniquely named options and 100,000 characters. Area above 0 to 1 million m² in m² or ft²; whole-window U-value 0 to 20 W/(m² K). Indoor -50 to 100°C and outdoor -100 to 100°C, entered in °C or °F; indoor must be at least outdoor. Degree days 0 to 20,000 K days; annual heating hours 0 to 8,784; heating efficiency/COP above 0 to 20; energy price explicitly entered from 0 to 100,000 per input kWh. JSON report, results CSV and full option comparison CSV.",
  "implementation": {
    "fields": [
      {
        "key": "areaUnit",
        "label": "Window area unit",
        "value": "m²",
        "type": "select",
        "values": [
          "m²",
          "ft²"
        ]
      },
      {
        "key": "climateMode",
        "label": "Heating exposure",
        "value": "Temperatures and degree days",
        "type": "select",
        "values": [
          "Temperatures and degree days",
          "Temperatures and heating hours",
          "Degree days only"
        ]
      },
      {
        "key": "temperatureUnit",
        "label": "Temperature unit",
        "value": "°C",
        "type": "select",
        "values": [
          "°C",
          "°F"
        ],
        "showWhen": {
          "climateMode": [
            "Temperatures and degree days",
            "Temperatures and heating hours"
          ]
        }
      },
      {
        "key": "inside",
        "label": "Indoor temperature",
        "value": 20,
        "type": "number",
        "step": "any",
        "showWhen": {
          "climateMode": [
            "Temperatures and degree days",
            "Temperatures and heating hours"
          ]
        }
      },
      {
        "key": "outside",
        "label": "Outdoor temperature",
        "value": 0,
        "type": "number",
        "step": "any",
        "showWhen": {
          "climateMode": [
            "Temperatures and degree days",
            "Temperatures and heating hours"
          ]
        }
      },
      {
        "key": "degreeDays",
        "label": "Annual heating degree days (K days)",
        "value": "",
        "type": "number",
        "min": 0,
        "max": 20000,
        "step": "any",
        "help": "Enter a sourced annual value at a suitable balance temperature. Fahrenheit degree days must first be divided by 1.8.",
        "showWhen": {
          "climateMode": [
            "Temperatures and degree days",
            "Degree days only"
          ]
        }
      },
      {
        "key": "heatingHours",
        "label": "Annual hours at the entered temperature difference",
        "value": 2000,
        "type": "number",
        "min": 0,
        "max": 8784,
        "step": "any",
        "help": "The entered indoor/outdoor difference is assumed constant for every entered hour.",
        "showWhen": {
          "climateMode": [
            "Temperatures and heating hours"
          ]
        }
      },
      {
        "key": "performance",
        "label": "Heating efficiency fraction or seasonal COP",
        "value": 1,
        "type": "number",
        "min": 0,
        "max": 20,
        "step": "any",
        "help": "Enter 0.8 for 80% fuel efficiency or 3 for heat-pump COP 3, consistently with the energy price."
      },
      {
        "key": "tariff",
        "label": "Fuel or electricity price per input kWh",
        "value": "",
        "type": "number",
        "min": 0,
        "max": 100000,
        "step": "any",
        "help": "Required. Use one currency and enter 0 explicitly to exclude energy cost."
      }
    ],
    "registrationFamily": "home-energy-planning",
    "input": true,
    "live": false,
    "presentation": "metrics",
    "inputMaxLength": 100000,
    "inputErrorCode": "HOME_ENERGY_PLANNING_TOO_LONG",
    "note": "Calculated on your device for up to 30 options. Enter whole-window U-values in W/(m² K), not centre-pane values or unconverted U.S. U-factors. First row is the comparison baseline.",
    "inputKeywords": [
      {
        "id": "home-energy-planning/window-heat-loss-calculator/options.header",
        "kind": "header",
        "code": "HOME_ENERGY_PLANNING_WINDOW_HEADER",
        "fold": "lower",
        "values": {
          "option": [
            "option",
            "Option"
          ],
          "area": [
            "area",
            "Area"
          ],
          "uValue": [
            "uValue",
            "U value"
          ]
        },
        "describedBy": [
          "Name the columns Option, Area and U value, in that order, or omit the header.",
          "Window options"
        ]
      }
    ],
    "experience": {
      "automatic": false,
      "single": false,
      "inputMaxLength": 100000,
      "inputMode": "text",
      "label": "Window options",
      "placeholder": "Existing,10,2.5\nReplacement,10,1",
      "help": "One option per line: name, area in the selected unit and whole-window U-value in W/(m² K). First row is the baseline. Up to 100,000 characters. Review the settings before running.",
      "helpParts": [
        "One option per line: name, area in the selected unit and whole-window U-value in W/(m² K). First row is the baseline.",
        "Up to 100,000 characters.",
        "Review the settings before running."
      ],
      "action": null
    },
    "mode": "explicit",
    "interactive": false
  },
  "execution": "Browser interface",
  "api": null,
  "browser_agent": {
    "supported": true,
    "name": "run_current_tool",
    "discovery": "WebMCP on the human page in a supporting browser",
    "verification": "See audit/API-AUDIT.md; availability is not verification"
  }
}

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