We want to put an addition on but we don’t know what to do about the HVAC system

My husband and I really want to put an addition on our house, but we aren’t really sure what we want to do about the HVAC system. The HVAC contractor that we were working with told us that we might have issues with heating and cooling the new addition because our existing HVAC system wasn’t quite powerful enough to do the job. This could also end up causing problems throughout the rest of the house. For instance, if our A/C unit was working overtime to try and cool off extra square footage throughout the addition, it would probably end up causing a lack of cooling elsewhere in the house. The HVAC contractor was concerned that this would be the case and he suggested that we just go ahead and upgrade our heating and cooling system to something larger that would work well throughout the entire house. Our other option was to put in a separate HVAC unit to heat and cool the other side of the house with the additional space. If we did that, then we could have zone control heating and cooling. I like the whole idea of zone control heating and cooling, because if we decide to be in another part of the house, we don’t have to worry about what the temperature is on the other side. My vote was for zone control, but my husband said that he would rather go with an HVAC upgrade. I guess we’ll just wait and see which one costs less. That’s usually the deciding factor for the two of us.
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