Hello Everyone, I would greatly appreciate anyone's advice on a project I am working on.

The project is in the Virginia Piedmont. The Hardwood Flooring is on the second floor of a large warehouse, potentially 6000 sq ft. I am considering buying unfinished utility grade oak. When I checked out the material on the pallet at the distributor, the look and knots seemed fine. However, I am concerned about the length of the planks and the width of the boards. The warehouse is sealed, and has a steel envelope, but will not be fully air conditioned. The air conditioning would only be in the office rooms, which make up less than 20% of the total floor space. There will also be hydronic heating but this might not be installed for a year or more. Apparently the average board length is not known by the distributor, but it looked like it could be only 1'~. The flooring would be going over OSB sub floor unfortunately. Does anyone have experience with this flooring type? Will I need a vapor retardant under the board? What is the best option for preventing the boards from cupping? I prefer mechanical fastening methods over glue if effective.

Thank you for reading. I look forward to everyone's insight.

-Mr. Wellboden

Utility grade can have lots of defective grain besides only knots. The edges don't have to all be there, shakes and whatever is left over from second and better. With a lower grade flooring, the mechanics can miss defective boards as they rush to get the installation finished. There will be defective boards that need to be graded out or trimmed against walls.
Short boards will be fastened down better since every board needs two fasteners, minimum. The waterproof kraft paper will keep the working area clean and dust free while the flooring is laid, being easy to sweep as the work is being done, compared to either plywood or OSB.
It is hard to justify this grade of flooring just because of price.
No heating for a year means that you will need to acclimate the wood between high and low moisture seasons when it is laid, or account for it with periodic spacers between rows as it is fastened down that will be removed before finishing.