​​Manual J Load Calculation Services   Load Calculation Service  aka heat load services

Our Team

Heat Load USA hires professionals and technicians who share our passion for excellence in all that we do. Your personal designer will oversee the project from initial consultation to final approval. We don’t rest until you’re delighted.

HVAC Load Calculation Services

Manual J Calculation

ACCA Manual D

You helped me out. My HVAC contractor could not do a Manual D.  You came thru.



Jill Smithwick,

Builder - California

Welcome.  Manual J Calculation 

Thanks guys. You did a great job. I got approval right away from the building department. 


Harvey Stoop,

HVAC Co. Owner

What Clients Say About Us


  • Manual J
  • Manual D
  • Manual S
  • Manual N (Commercial heat load)
  • Res Check and Com Check

HeatLoad USA, a subsidiary of Building Sciences LLC provides a variety of engineering services to HVAC contractors, builders, architects and homeowners all over the USA.  These services include: