Terms of Use

Prices are national ranges from published sources; your actual cost depends on your region, home, equipment and contractor. Sizing results follow the ENERGY STAR room method and are not a substitute for a Manual J load calculation by a qualified contractor.

Content on this site is general information. It is not engineering, electrical, gas or legal advice. Only attempt the checks described as safe for homeowners. Gas, refrigerant and high-voltage work must be done by a licensed technician.

The site is provided "as is" without warranties of any kind. To the extent allowed by law, we are not liable for decisions, repairs, purchases or damages based on the information or results shown here.

Actual heating and cooling loads and prices depend on things a free tool cannot see: local climate, insulation, window type and sun exposure, duct leakage, the condition of existing equipment, permits and local labor rates. Confirm the final size and price with a licensed contractor before you buy.

You may link to any page and share results. Copying the tools, text or graphics in bulk for another website is not allowed without written permission.

• Do not scrape, copy or query the site in bulk with automated scripts.
• Do not try to interfere with the site, its servers or its security.
• Do not present results from the tools as a certified load calculation or engineering document for permits, inspections or code approval.

We link to sources and may show ads from third parties. We are not responsible for their content, products or practices.

We may update these terms; the date at the top shows the latest version. Questions: [email protected].