Clearly define the thermal (heated) envelope and the airtight layer.Floor plans:make installation zone(s) compact and concentrated, e.g. by placing bathrooms above or next to kitchens, etc.consider routing of, and space for, ventilation ducts.Separate cold basement if present:airtightno cold bridges.Acquire local climate data in a form suitable for use with PHPP. Verify if calculated by Meteonorm