Sizing A/C and ERV for my house

[Retread]

Me: about 10 years working off and on Commercial A/C over 4 decades 6 years in this decade for Lennox (I know heard all the issues with them don't want to go there) so no install and no residential experience. Not doing HVAC now but building my retirement house.

House: We are building with SIP panels in Oklahoma. 1/2" OSB on both sides glued to 6" foam for walls and 8.5" foam for roof. all joints are foamed and taped. I will tape joints and use a spray sealer on outside that is a water seal but allows vapor to go out according to my designer. The air infiltration is almost zero so I will need fresh air intake so using an ERV makes sense. I have worked on the big ERV units for big box stores but not the residential stuff.
2730 Sq Ft ranch with 10 ft ceiling and 1000 sq ft of that will have cathedral ceilings peak at 15ft.

On sip houses they recommend down sizing from normal requirements to 60% of what you would normally use.

Questions:
Where should I go for A/C load calculations for this type house?
is the ASHRAE 62.2 fresh air guide (about 100 cfm) enough for an air tight house?
Plan is to pull air from bathrooms and fresh air to bedrooms and living area. Does this sound right?
What am I missing?

Thanks for your time

[teddy bear]

Good plan. Suggest icing on the cake, a small whole house dehumidifier like the the Ultra-Aire 120 t maintain <50%rH during evenings and rainy days with high outdoor dew points which are common in "green grass" climates like OK.

The Ultra-Aire is a high efficiency dehu with a merv 13 air filter that can be connected to the ERV and A/C.

Ultra air will maintain low %RH by removing upto 5 lbs. of moisture per hour.

Interested in hearing from you about details and interest.

REgards Teddy Bear

[dan sw fl]

Me: about 10 years working off and on Commercial A/C over 4 decades 6 years in this decade for Lennox (I know heard all the issues with them don't want to go there) so no install and no residential experience.
Not doing HVAC now but building my retirement house.

House: We are building with SIP panels in Oklahoma.
1/2" OSB on both sides glued to 6" foam for walls and 8.5" foam for roof.

All joints are foamed and taped.
I will tape joints and use a spray sealer on outside that is a water seal but allows vapor to go out according to my designer.
The air infiltration is almost zero so I will need fresh air intake so using an ERV makes sense.

I have worked on the big ERV units for big box stores but not the residential stuff.

2730 Sq Ft ranch with 10 ft ceiling and
1000 sq ft of that will have cathedral ceilings peak at 15ft.

On sip houses they recommend down sizing from normal requirements to
60% of what you would normally use. __ Use ACCA Manual J ROOM-BY-ROOM Load Calculation

Questions:
Where should I go for A/C load calculations for this type house?

Is the ASHRAE 62.2 fresh air guide (about 100 cfm) enough for an air tight house?
Plan is to pull air from bathrooms and fresh air to bedrooms and living area.
Does this sound right?
_________ Yes, I might design for ~ 150 CFM & operate it ~ 2/3rds of the time.
_________________ Fresh Air can be provided in the HVAC Supply Ductwork, IF you are using a conventional air distribution system.
_______________ Use UltraAire model 120

Your NEW Construction project is my favorite structure/BUILDING THERMAL ENVELOPE
to develop an effective and economical Residential HVAC System design.

Your Heat Gains and Heat Losses should be VERY Low
Pat attention to detail on Cathedral Ceiling insulation.

____ Personalized, Custom Service
_________ www.mysimplifiedhvac.com __ 5 Pages
xx
https://www.rses.org/assets/servicea...al/630-148.pdf

Alternates:
1. Multi-Split System(s)
2. Hybrid (Heat Pump & Furnace) System

[dan sw fl]

___ 19.3'F Winter
___ 99.5'F Summer

[kdean1]

You may want to investigate the CERV2 by Build Equinox. It is a ventilator with a small compressor to heat or cool the incoming air, not just exchange heat as most ventilators do.
I have not used one nor installed one as our area does not have many passive or net-zero homes. I did ask about prices - YES they are expensive but this may be just what you need.