Terms of Use

Effective 2026-10-28.

Information only

Content and calculator results are general estimates for planning and education. They are not a substitute for a load calculation, inspection or advice from a licensed contractor who has seen your home.

Safety

Work involving refrigerant, gas appliances, combustion venting or line-voltage wiring can be dangerous and is regulated in most places. Follow local codes and use qualified professionals.

No warranty

The site is provided as is. We work to keep it accurate but do not guarantee that any figure is correct for your situation, and we are not liable for decisions made using it.

Content

You may link to and quote short passages with attribution. Please don't republish whole pages.