Since cooling requires forced air systems, the HVAC will be completely forced air. Ventilation trunks will take minimal routes to the appropriate rooms, and the system will be matched to the needs of the building. This will provide comfort throughout the year. To help accommodate, the great room will have an electric fireplace which will be able to heat a room pretty quickly. The fireplace will be an optional item, and not required.
To assure that there is a good interior envelope, the perimeter will be spray foam insulation of at least 4″. This is to keep the indoor temperatures indoors. The interior perimeter walls will have all of the infrastructure running through it, and those walls will use padded foam insulation to help provide a higher R Value.