HVAC Heat Load Calculation

I'm looking to have an HVAC heat load calculation done for an industrial building that is between 10,000 and 50,000 sq ft. I prefer to have a software-assisted calculation completed as this is the most accurate method to measure the load. I need an experienced professional who has a working knowledge of relevant engineering fundamentals and software engineering techniques. The successful bidder for this project must be able to produce a detailed report that outlines a comprehensive approach for calculating the heat load of the HVAC system in question. Additionally, the results from the calculations must be presented in a user-friendly format so that it can used to make informed decisions about system design and implementation.