BTU Calculator FAQ

FAQ

Common BTU & HVAC Questions

Real answers to the questions homeowners and contractors ask most. Click any question to read the full answer.

What AC unit should I get for a sunny 550 sqft apartment in California?
What AC tonnage do I need for a 15×30 room on the top floor?
How do I pick the right size AC for a small bedroom or office?
Is a higher BTU air conditioner always better if the wattage is similar?

ASHRAE Standard Reference

Calculations based on ASHRAE Standard 183 & Manual J methodology

IECC Climate Zone Data

Covers all 8 IECC climate zones across the continental United States

Free ASHRAE-compliant BTU calculators for every room type. No sign-up required. Results in seconds.

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