Terms of Use

Use of the site

HowManyBTUs.com provides calculator-based estimates and educational content to help with heating and cooling sizing (BTU/hr) and related planning (for example: AC sizing, heat pump sizing, room-by-room estimates, and energy-cost approximations).

You may use the calculators free of charge for personal, non-commercial use. Commercial use (including embedding, reselling, or redistributing the tools, outputs, or content) requires prior written permission.

You agree not to misuse the site, attempt to disrupt its operation, or scrape/automate access in a way that degrades performance for others.

No professional advice

The calculators and content on this site are provided for informational purposes only and do not constitute professional HVAC engineering advice, building code guidance, electrical or gas-fitting advice, or any other professional service.

Proper HVAC sizing and installation can depend on many factors not captured by simple inputs, including building envelope details, duct design, ventilation requirements, latent (humidity) load, local code requirements, and equipment specifications.

You should consult a qualified professional for whole-home sizing and equipment selection (e.g., Manual J / Manual S), new installations, replacements, or major upgrades, duct design, airflow issues, or indoor air quality concerns, gas appliance work, electrical work, or permit/code compliance, and commercial or multi-unit building projects.

Safety disclaimer

Heating and cooling equipment can be hazardous if installed or used incorrectly. Always follow manufacturer instructions, local building codes, and applicable safety standards.

In particular: do not attempt electrical or gas work unless you are qualified and permitted to do so, follow safe practices for ladders, attic work, and confined spaces, ensure proper ventilation and combustion safety for fuel-burning appliances, use correct breaker sizing, wiring, and grounding for HVAC electrical components, and follow refrigerant handling rules (certification may be required).

If you suspect an unsafe condition (gas smell, sparking, overheating, unusual odors, carbon monoxide concerns), stop use and contact a qualified professional immediately.

Accuracy of information

We strive to keep the calculators and content accurate and up to date using commonly accepted sizing heuristics and reference approaches. However, we make no guarantees regarding completeness, accuracy, or applicability to your situation.

Calculator results are estimates based on the inputs you provide (dimensions, ceiling height, windows, insulation, sun exposure, occupancy, etc.), assumed default factors and simplifications, and generalized climate/region settings (where applicable).

Actual heating and cooling needs may vary due to air leakage, duct leakage, attic/roof conditions, and insulation defects; humidity (latent load), ventilation, and infiltration differences; shading, glazing type, orientation, and window performance; internal gains (appliances, electronics, cooking, lighting); and equipment efficiency, airflow, and installation quality.

Best practice: Use these estimates for planning, then confirm final sizing with a qualified HVAC professional.

Limitation of liability

To the fullest extent permitted by law, HowManyBTUs.com and its operators shall not be liable for any losses, damages, injuries, costs, or decisions arising from use of or reliance on calculator outputs or site content; incorrect sizing, purchasing decisions, or installation decisions; energy costs, comfort issues, humidity problems, or equipment performance; errors or inaccuracies in calculations or content; or site downtime, data loss, or technical malfunctions.

You use this site entirely at your own risk. You are solely responsible for verifying results, following applicable safety guidance, and complying with local codes and manufacturer instructions.

The site is provided on an “as is” and “as available” basis, without warranties of any kind, whether express or implied.

Affiliate links disclosure

This site may include affiliate links to retailers (including Amazon). If you click an affiliate link and make a purchase, we may earn a commission at no extra cost to you.

Product mentions are provided for convenience and relevance to the topic. You are never required to purchase anything through affiliate links.

For more details, see our Affiliate Disclosure.

External links

This site may contain links to third-party websites for additional information, product purchases, calculators, or reference materials. We are not responsible for the content, accuracy, products, services, or practices of external sites.

External links are provided for convenience only and do not constitute endorsement.

Changes to these terms

These terms may be updated from time to time to reflect changes in the site, legal requirements, or practices. The latest version will always be posted on this page with an updated “Last updated” date.

Continued use of the site after changes are posted constitutes acceptance of the updated terms.

Contact

Questions about these terms can be directed to: support@howmanybtus.com