Section 6 of the International Building Code defines types of construction for buildings. The type of construction that you select is important because it tells you how big and how tall a building you can construct for your occupancy.
For small commercial projects, the most common construction types are V-A and V-B. (The V is the Roman numeral 5, so 5-A and 5-B).
V-B is the least restrictive building type with regard to materials. You can build your building out of any material and it doesn’t need to be rated. It is also the most restrictive in terms of size restrictions in Table 503.
V-A gives you a lot more options if your building can’t work as an unrated structure. In order to move from 5-A to 5-B you must provide a minimum 1-hr rating for your structural frame and/or bearing walls and your floor and roof construction including supporting beams and joists. These ratings can be achieved through fire resistant construction of the assemblies or by providing an approved automatic fire sprinkler system. Even with a sprinkler your exterior walls have to be rated.
If you choose to use the fire sprinklers to move from V-B to V-A you can’t double dip and use them for other area increase factors.