Conditioned floor

For the most part a floor is a floor especially if it contains conditioned space. See floor area definition. The only exceptions I can think of might be a mechanical penthouse or mezzanine. The floor area in Table G3.1.1A is qualified with the word conditioned. The number of floors is not. See G3.1.1.

You must count all the floors in our opinion.

Hi Marcus/All, Just to clarify. In the clause G3.1.1 of Appendix G, it was mentioned that "the baseline building design shall be based on usage, number of floors, conditioned floor area and heating source as specified in Table G3.1.1A". We have a six storey warehouse project with only less than 10% of the floor area is conditioned (about 100,000 ft2). According to Table G3.1.1A, since our building is more than 5 storey, we have to use System 7 or 8 even though our conditioned area is less than 150000ft2. Am I correct? Appreciate your advice. Many thanks.

Yes there is an "or" in between the number of floors and the square footage. So if either condition is present then that is the system type. Again this is our opinion and interpretation and I could understand another opinion based on just the conditioned floors. We do not think the standard language supports that interpretation however these issue are often not completely clear in all cases.