See NEC 220.30. This usually comes in smaller than the standard calculation. You also must have a service or feeder rated at 100A or more in order to use it (so I think you're OK with a 100A subpanel if its on a 100A feeder).

When I run your numbers with the optional calculation, I get 90 amps including a dryer. This was based on:
3.92 KVA living space
4.5 KVA small appliance circuits
5 KVA Dryer
9.5 KVA range
1.6 KVA Dish Washer
.98 KVA Microwave
1.18 KVA DIsposal
1 KVA Garage Door Motor
0.7 KVA Attic Fan

This comes to 28.38 KVA. The first 10 KVA are 100% and the remaining is 40%. So this reduces the load to 17.35 KVA. Then we add the Air Conditioner at 4.24 KVA giving a total of 21.6 KVA which is 90A.

About the only thing I can comment on your standard calculation you included is what air conditioner amp rating did you use? Was it MCA or FLA+RLA? If its MCA, that already has the 25% factor for the largest motor so you can remove that item from the calculation.


Mark
Kent, WA