Studio Matrx Monthly · Volume 1 · Issue 1 · June 2026
Amogh N P
 In loving memory of Amogh N P — Architect · Designer · Visionary 
Door Energy Savings Calculator

Door Energy Savings Calculator

See how much cooling energy a lower-U external door saves. Enter the door area, your climate zone, current vs proposed U-value and your electricity tariff — get annual ₹ saved and a simple payback on the 18% GST door premium. Indicative India 2026.

Your door upgrade

Hot summers, mild winters. ΔU = 3.5 W/m²K. Savings ≈ area × ΔU × cooling-degree-hours ÷ COP (~3) × tariff. Indicative India 2026 (Eco-Niwas Samhita / ECBC framing) — bands only.

Estimated annual cooling-energy saved

0

173 kWh/yr · simple payback 15.3 yrs

₹ / year

₹1,386

Payback

15.3 yr

simple

Net @ 10 yr

₹-7,380

saved − premium

  • 10-yr energy saved13,860
  • Door premium (incl. GST)21,240
  • Premium incl. 18% GST3,240 GST

10-year energy saved vs the all-in door premium. Indicative — confirm with an EPD / energy consultant.

Annual ₹ saved by climate zone

Same door area, ΔU and tariff applied across every zone. Hotter, longer cooling seasons save more. Your selected zone is highlighted.

Worth upgrading this door?

DesignAI weighs U-value, thermal breaks, glazing and your climate against the price — and flags when a cheaper fabric upgrade beats a premium door.

Assumptions & caveats

  • Annual cooling-energy saving ≈ area (m²) × ΔU (W/m²K) × cooling-degree-hours ÷ COP (~3) × tariff (₹/kWh). Only the conductive heat-gain difference is modelled — not air-leakage, solar gain through glazing, or shading.
  • Cooling-degree-hours are indicative per climate zone and assume the door faces conditioned space cooled most of the season. Real savings vary with orientation, occupancy and AC behaviour.
  • U-values are typical reference figures. The door premium and 18% GST are your inputs; payback is simple (undiscounted), ignoring tariff inflation and maintenance.
  • These are indicative estimates — confirm with a manufacturer EPD / energy consultant. Not a substitute for a measured energy audit or green-building assessment.

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