apartment calculation

[sarosa]

I have a potential job at an apartment complex.

We will change out existing unit old bulldog pushmatic panels

with new panels and we will add 1 washer, 1 dryer and 1 microwave circuit per

each unit. The existing unit panels are 80amp panels with (4) 15amp general light and plug

circuits and (1) 240v AC 30amp circuit. My question is how do I do a load calc. on this existing

building to see if I can add these circuits on existing service. There are 12 units per building.

Each unit is about 900 sq. ft.

Thanks