You should first make sure that the building will be as large as you need it to be. You will need to consider the number of people you want to fit at the same time. Before you do this, check city codes to find out how big buildings have to be in order to fit the number of people you are hoping for, and then tell the construction company those specifications. Most experienced companies will be able to tell you if it is realistic, or if you need a larger or smaller structure. Your budget will, of course, need to be considered here, so make sure that you have the funds to get the outcome that you want.
You also need to make sure that your theater will have the correct number of rooms before construction can begin. Think about the number of individual auditoriums you want, keeping in mind that the more you have, the more movies you can show at once. This can increase your profits, but you have to have the budget for it upfront. You should also find out how many restrooms you will need in relation to the auditoriums. The city will probably have some regulations regarding the amount, so find out from the city government before the theater is built.
Another decision to make is the amount of snack bars you will have. This should be based on the amount of people you can fit in the building and the number of auditoriums. Plus, if you have more than one floor, you will probably need more than one snack bar. In fact, many single-story theaters even offer more than one in order to keep lines shorter and sell more concessions. You also need to consider how large you want each snack bar to be, especially if you only want one, since it should be quite large to adequately accommodate all of your patrons.