Quick Load Estimator

Rule-of-thumb cooling tons, heating MBH, and supply CFM from square footage
Inputs
Estimated Results
Cooling
tons
Cooling
BTU/hr
Supply CFM
CFM
Heating
MBH
SF / Ton
ft² per ton
CFM / SF
CFM per ft²

Rule-of-thumb estimates only — not a substitute for a Manual J or block load calculation. Use for early feasibility and equipment pre-selection.

Reference — Typical Ranges
Building TypeSF / TonCFM / SFHeat (BTU/SF)
Office300–4000.8–1.225–40
Retail200–3001.0–1.530–50
Restaurant100–2001.5–2.550–80
School250–3501.0–1.530–50
Medical Office200–3001.0–1.835–55
Warehouse500–8000.3–0.610–20
Hotel350–5000.7–1.020–35
Residential400–6000.5–0.820–35
Server / Data50–1502.0–5.0
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