Fresh Air Requirement Calculator
Work out the fresh (outdoor) air a space needs for good indoor air quality. Set the area, occupancy and space type to get the ventilation rate in CFM and m³/hr — using the per-person-plus-per-area method (ASHRAE 62.1 style).
Rates used: 5 CFM/person + 0.06 CFM/sq ft for a office.
= 75 m³/hr of outdoor air · 4 people + 400 sq ft.
This is the outdoor (fresh) air for IAQ — different from total room airflow (see the air-changes calculator). Size the fresh-air fan / treated-fresh-air unit at or above this.
A planning estimate. It uses indicative ASHRAE 62.1-style per-person and per-area rates; the exact values depend on the specific occupancy category, the applicable code (ASHRAE 62.1 / NBC / ISHRAE), and factors like air-distribution effectiveness. Use it to frame the fresh-air requirement; an MEP engineer designs the ventilation system.
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The due-diligence checklist for builder floors — title, construction quality, layout and red flags
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Decode any floor plan like a pro — symbols, scale, dimensions, circulation and red flags
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An indicative equipment + installation budget for your home's air conditioning — by AC type, tonnage and number of units, with a realistic range.
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What your AC costs to run each year — from tonnage, BEE star rating, hours and tariff — plus how much a higher star rating saves.
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