I am building a new house in the piney woods of east TX. H/C area of the house is 2800. All windows face east and west but most are under covered porches. The sun doesnt really hit the windows due to so many trees around. Spray foaming walls and roof deck with open cell foam. Had the HVAC contractor come out, (very reputable, highly recommended,never heard any complaints, excellent service company, does many foam houses) come out. This is what they recommended from looking. They had not ran a Manual J yet and are going to. They said 1 - 4 ton Carrier Infinity variable speed Heat pump to service most of the house, and 1 - 2 ton to service the master suite, utility, mudroom. The spray foam guys came and said that is way over sized and they ran a manual J that said I need 3.4 tons total. When I told the HVAC guys, they said that is true, and that I will need approximatly 3 tons total to cool the house. They said the reason they went with a 4 ton and 2 ton variable speed was 90% of the time I will be running both units @ 50% essentially 3 tons. In the case we have a bunch of people over or it reaches the 110* days it usually does in June, July August in TX, that it then has the capacity to take care of that. HVAC guys said their # 1 concern is humidity control and comfort. Does setup they recommend seem appropriate?