# Crawl Space Ventilation Calculator
I'll create a beautiful, professional crawl space ventilation calculator that helps homeowners and contractors determine the proper ventilation requirements for crawl spaces based on building codes and best practices.
Let me build this step by step:
{"name": "create_file", "arguments": {"path": "/index.html", "content": "\n\n\n \n \n \n Crawl Space Ventilation Calculator | Calculate Required Vent Area\n \n \n \n \n\n\n
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\n VentCalc Pro\n
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\n \n IRC 2021 Compliant\n
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Crawl Space Ventilation Calculator
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Calculate the optimal ventilation requirements for your crawl space based on square footage, soil conditions, and building code standards.
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Calculate Vent Requirements
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Enter your crawl space specifications below
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Soil & Installation Conditions
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\n \n Normal / Average Moisture\n Wet / High Water Table\n Dry / Arid Climate\n \n \n \n \n \n \n
\n Required Net Free Vent Area\n —\n square inches\n
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\n Ventilation Ratio\n —\n of floor area\n
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\n Recommended Vent Count\n —\n standard 8\"×16\" vents\n
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Placement Recommendations
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Why Proper Ventilation Matters
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Adequate crawl space ventilation prevents moisture buildup, reduces the risk of mold and wood rot, and helps maintain structural integrity. Poor ventilation can lead to costly repairs and health hazards.
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Understanding the Calculations
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The standard ratio is 1 sq ft of vent area per 150 sq ft of crawl space. With a properly installed vapor barrier, this can be reduced to 1:1500. Our calculator applies these ratios based on your inputs.
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Vapor Barrier Benefits
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A Class I vapor retarder covering the ground significantly reduces moisture migration, allowing for 90% less vent area. This can be beneficial in extreme climates where too much ventilation causes issues.
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Building Code Reference
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\n IRC R408.1\n
Standard Ventilation
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Minimum 1 sq ft of net free ventilating area for each 150 sq ft of crawl space floor area.
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\n IRC R408.2\n
With Vapor Retarder
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When ground is covered with Class I vapor retarder, ratio may be reduced to 1:1500.
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\n IRC R408.3\n
Vent Placement
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Vents shall be placed to provide cross ventilation within 3 ft of each corner.