Quote Originally Posted by drewscm View Post

My question: Should I spend the extra money to have a zone in the basement? I haven't had anyone come out and quote yet but I do know some HVAC guys and one says it shouldn't need to be if setup right, and the other says being nine foot ceilings with the windows and slider it should be zoned.

What are you suggestions from past experiences?
Having a similar home with a finished basement, here are my comments.
Number one is to keep the humidity in the space below 50%RH throughout the three warm seasons. This avoids near condensation air near the cold concrete surfaces to prevent mold. This eliminates any possibility of basement odors and excellent comfort. Also fresh air when occupied is important as basement walls do not breathe. I use a Ultra-Aire whole house ventilating dehumidifier to take air from the mainfloor and blend it with 70-80 cfm of fresh air from outside, filter the air, dehumidifiy if necessary and cirulate the air through out the basement throughout the year. The recirculation of the air helps maintain dry warm conditions throughout the home.
There is no cooling load in basement space. In fact most basements are to cool during the summer just from the cold a/c ducts blowing air into the rest of the home.
During winter, open the supply ducts to allow more heat into the basement. VS low speed furnace operating on "low" througout the year is also helpful to maintain uniform temp throughout the home. The dehumidifier fan recirculating the upstairs air to the basement 24/7 also helps maintaining uniform temp throughout.
Maintaining <50%RH is most important. This allows carpet on concrete without musty odors.
Regards TB