Lighting Building Area method

If the building is an office building with a small part retail and restaurant how should the areas be calculated for lighting when using the Building Area method?? The space usage types listed in PIf3 are: Office, retail, restaurant, circulation space, recycling space, changing rooms, bicycle storage, general storage, mechanical. Should the total gross area be included for lighting calculations or only office, retail and restaurant? If circulation, spaces, storages, changing rooms, mechanical should be included. Should they then be included under offices since that is the largest part (resturant and retail are only 2,5% of total area)