Window Quantity Calculator
Estimate how many windows your home needs from its floor area to satisfy daylight and ventilation norms. Tied to NBC 2016 rules of thumb — indicative for India 2026; always verify your local bye-law.
Your home
NBC 2016 commonly targets a glazed opening of ~1/10 (10%) of floor area for daylight, with an openable area of about half that for ventilation. Each window here is 16.0 sq ft. Rules of thumb only — local bye-laws, room depth and orientation govern the real requirement.
Suggested windows
0 windows
for 1,000 sq ft at 10% glazing · about 1.0 per habitable room
Glazing area needed
100 sq ft
for daylight
Openable area needed
50 sq ft
for ventilation
Your window area
16 sq ft
each window
Total provided
112 sq ft
meets target
Place windows where the light works
DesignAI positions and sizes windows per room — for daylight, cross-ventilation and your climate.
Related Guides — Deep-dive reading
Bay Windows for Indian Homes: Light, Floor Area and a Window Seat
How an angular three-unit bay adds floor area, light from three angles and a window seat, and what it takes to build one well in India.
Windows & GlazingGreen Building Window Design for India
The fenestration scorecard — exactly which window decision earns which IGBC, GRIHA or LEED credit, and the numeric thresholds to hit
Windows & GlazingNational Building Code Window Requirements
What NBC 2016 requires of a home window in India: glazed area for light, openable area for ventilation, by-room minimums, ceiling heights and the bye-law that actually governs.
Windows & GlazingRelated Tools — You may also find these useful
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Estimate a room's average daylight factor, daylit depth and natural-light adequacy from glazing and VLT.
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