There are many types of flooring options, and for commercial applications, there are several options. Gypcrete is a sub-floor option that is often used in multi-family and commercial buildings due to its sound control and fire control properties. Gypcrete is a cousin to concrete and made of a lightweight sand mixture that makes it much lighter than concrete, though less durable.
Only certain types of flooring can be laid over the top of a Gypcrete subfloor, which is laid down over a wood subfloor. It has great leveling abilities, and is very light-weight, especially when compared to standard concrete. However, nail-down flooring options such as hardwood will not work over gypcrete, and the surface can be gritty and dusty which can make it tough to adhere to. Carpeting is the best flooring type to lay down over gypcrete. If you are laying a floor over the top of gypcrete, and it's an adhesive-type installation, check the adhesive properties to be sure that it is compatible with gypcrete and can adhere even with the duty and gritty gypcrete properties.
Though lightweight and often considered easier to install than concrete subfloor, gypcrete can have its disadvantages such as the limited flooring types that it is compatible with. It can't support as much weight as its heavier concrete cousin, and is prone to cracking in its lifetime, and damages must be repaired by a licensed contractor. In fact, gypcrete also must be installed by a licensed professional, so the DIY option is out of the question.
If you are installing a floor in an industrial capacity and need it to be fire and sound resistant, gypcrete is the way to go. Be sure to check with your local building codes to know whether or not it's an accepted building material, and if it will meet building code standards.