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Location & Room Data

City

Room Type

Floor / Position

🧭 Building Rotation

0°

0°45°90°

Area (m²)

Ceiling height (m)

To Override (°C)

Ti (°C)

Roof Type

Roof area (m²)

🏠 Suspended ceiling / Plenum

Gap between ceiling and roof/floor above

🔥 Internal Loads Total: 0 W

ItemQtyWHFTotal W

Total 0 W

HF = Heat Factor · People: 70W sensible · Lights: ×1.25 · Fridge: ×1.30 · Server: ×1.00

Outdoor RH% (Infiltration Latent)

Indoor RH%

Typically 50–60%

Slab edge (m)

Floor band on the facade

Include the plenum + slab band in the cooling load
That strip of facade faces outdoors too, so the a/c has to remove its heat.

📐

Floor Plan

Use drawn plan

Tick “Use drawn plan” to draw the room outline instead of typing wall areas. Wall areas are then derived from the drawing — length × ceiling height − glass — and each wall keeps its true bearing instead of being rounded to N/S/E/W.

🧱

Walls by Direction

Exterior = CLTD+Solar (R from slider or Custom) | Interior = actual ΔT, no solar | None = not calculated

🪟

Glass by Direction (exterior walls only)

💨

Air Infiltration

Checked = sealed (reduces ACH) · Unchecked = still leaking

Total ACH

0.80

Sealing level

—

Infiltration Load

— W

Sensible + Latent

📈

COP/EER Comparison — Cost/yr

AC Grade	COP	EER	kW	kWh/yr	Cost/yr (฿)	Save vs COP 2.0

Uses the same hours · days · Load Factor

📉

Impact of Your Envelope

📊

Heat Load Breakdown

Load proportion

Envelope — heat transfer by surface

Detail table

Item	W	BTU/hr	%

ASHRAE CLTD/CLF (tropical) · Safety factor 10% · Baseline: plastered brick R=0.47 · clear glass R=0.18 SC=0.87 · concrete roof R=0.20
Envelope flux (OTTV) is an area-weighted average heat flux through the envelope, useful for comparing one design against another. National energy codes that use the term OTTV — Thailand’s BEC, Singapore’s BCA and others — each define it with their own equation and their own tabulated coefficients, so this figure is not a substitute for a code compliance calculation.